Prophylactic antibiotics for patients with artificial joints undergoing and dental surgery: necessary or not?
oral
E. A. Field, M. V. Martin Department
of Clinical Dental Sciences,
-
~..
University of Liverpool, ~..
.-
Liverpool
..~
SUMMARY. Prophylactic antibiotic cover for certain oral and dental procedures for patients with artificial joints is a controversial issue. This paper examines the evidence supporting the use of antibiotic cover and concludes that routinely, for the majority of patients with artificial joints, it is not justified. Certain medically compromised patients with artificial joints have a slightly increased risk of infection and, under these circumstances, antibiotic prophylaxis may be justified. The antibiotic recommended for this group is cephradine or in the case of penicillin allergy, clindamycin. Preoperative dental fitness is mandatory for all patients who are to receive artificial joints. This information will be of interest to the oral and maxillofacial surgeon in his own clinical practice, and when giving advice to local general dental practitioners.
INTRdDUCTION
known to cause transient or prolonged bacteracmias have also been implicated in infections of TJR (Blomgren, 1981; Cioffi et al., 1988).
Replacement of severely damaged joints with artificial prostheses is one of the major post-war surgical developments. Of all forms of joint replacement, that for hips represents the most outstanding innovation. Total hip replacement (THR) is an example of a technique that can radically improve the quality of life at an acceptably low cost (Office of Health Economics, 1982). Data for 1978 showed that there were about 28O@l THR operations carried out in NHS hospitals in England and Wales (Office of Health Economics, 1982) and 25OOOt.lcarried out throughout the world every year (Hori et al., 1978). The next most frequent total joint replacement (TJR) is arthroplasty of the knee, but this is technically more difficult and the failure rate higher. Other joints replaced have included the shoulder, ankle, wrist, finger, elbow and temporomandibular joints, but all to a lesser degree than the hip joint. Total hip replacement is undertaken mainly for cases of degenerative joint disease (osteoarthritis) and, to a lesser extent, for rheumatoid arthritis.
The consequences
of an infected hip replacement
Deep infection of a THR invariably leads to loosening of the prosthetic components and this usually neccssitates removal followed by an exchange arthroplasty, if possible. Alternatively, the components are removed leaving a pseudoarthrosis which results in large skeletal defects, shortening of the limb and disastrous physical impairment (Salvati, 1984). Failure to satisfactorily manage an infected hip replacement may result in a chronic, persistent osteomyelitis and possible hind quarter amputation or death (Klenerman, 1984). Such infection, therefore, carries an enormous crippling morbidity and the additional burden of increased health-care costs for hospitalisation and rehabilitation (Salvati, 1984). The majority of orthopacdic surgeons who must deal with the potentially devastating consequences of an infected joint replacement now recommend antibiotic prophylaxis for dental patients with a TJR (Stinchfield et al., 1980; Jaspers & Little, 1985; Shay & Lloyd, 1988). Klenerman (1984), in a paper on the infected cndoprosthcsis, advised that patients with total hip replacement must bc warned of the possible implications of intercurrent infections, dental extractions and urinary tract operations and felt that dental surgeons should bc alert to the necessity for broad spectrum antibiotic cover in these situations. Paradoxically, one survey has shown that of those orthopaedic surgeons who responded, the majority advised a prophylactic antibiotic regime for dental patients with a TJR, although they considered that
Infection of artificial joints
The most serious complication of TJR is infection (Mulligan, 1980) and this occurs either at the time of operation or from haematogcnous spread from distant foci of infection. Infection of an endoprosthesis may appear shortly after the replacement or months or years after an apparently benign postoperative period. Later infections are usually caused by micro-organisms which have remained latent since the time of operation or have metastasised from other infected sites (for example, skin, respiratory or urinary tracts). Certain dental procedures 341
342
British
Journal
of Oral
and Maxillofacial
Surgery
there was either no relationship, or a minor one, between dentally-induced transient hacteraemias and later prosthetic joint infections (Jaspers & Little, 1985). Bone cements impregnated with gentamicin also help to prevent deep sepsis postoperatively, but there is evidence from animal studies that antibiotic-loaded acrylic cements do not provide protection against later haematogenous infections (Klenerman, 1984). Haematogenous
infection of the THR
Improved surgical techniques at the time of the operation have greatly decreased the incidence of early infections in THR but late infections still present a problem. These are mainly thought to be caused by bacteria of haematogenous origin. Experimental haematogenous infection of total joint prostheses has been produced in experimental animals using a strain of Staphylococcus aureus. Blomgren (1981) induced bacteraemia in rabbits, which had human finger joint prostheses cemented in both knees, 6 to 8 weeks postoperatively. A third of the joints become infected with Staph. aureus after 25 days. However, over half the experimental animals died and the bacterial inoculation was probably large enough to represent a scpticaemia, rather than a transient bacteraemia which commonly arises in patients undergoing oral and dental procedures (Hirschmann, 1984). Several case reports and papers have given accounts of late infections of THR secondary to distant foci of infection and these have been collected and analysed by Biomgren (1981). Table 1 summarises the bacterial findings in these cases and Table 2 lists the primary foci of infection in the cases that Blomgren found reported in the literature. There does not seem to be a time limit to the period that a patient is at risk from haematogenous spread and infections have been reported to occur up to 5 years after TJR (Mulligan, 1980). The TJR is at risk from bacteraemia because the cement which holds the endoprosthesis in place reduces the vascu1- Aetiologic bacteria in 61 hacmatogenously infected total hip replacements (57 patients) reported in the literature lY7>XfJ (Blomgren, lY81)
Table
Frequency Bacteria Sraplryl0coccu.s P-Streptococci Pncumococci
Number amens
Staphylococcus epidermidis Escherichia coli Proteus mirubilis
W)
28 9 5
46 15 8
s
8
4
8
4
7
Pseudomonads
I
7
Mycohacrerium ruherculosiv Salmonella ryphimurium Viridans sveptococci and Prowus mirahilis Bacreroides frugilis Aeromonas hydrophiliu
I
1 1 1 1
Table 2 - Primary foci of infection in 61 haematogenously infected total hip replacements in the literature 1973-W (Hlomgren, Primary
1981)
foci
Respiratory tract Dermal Urinary tract Dental Castro-enteric tract Otitis media Parotitis Unknown
Number 11 10 9 7 4 1 I I4
larity and infection tends to develop at the interface of the bone and prosthesis. Data from a number of studies has shown that patients with rheumatoid arthritis are particularly susceptible to late infection after TJR because of their altered immune response and general debilitation (Peterson, 1980; Poss et al., 1984; Cioffi et al., 1988). The incidence of deep sepsis following THR is also significantly increased if the patient has had a previous hip operation or has undergone revision surgery for previous failure (Poss et ftf., 1984). The risk of haematogenous dental procedures
spread from oral and
Many oral and dental procedures produce a transient bacteraemia. These include extractions, scaling, oral and periodontal surgery and drainage of abscesses. Such procedures usually produce a bacteraemia which is small in quantity, asymptomatic and short lived (Hirschmann, 1984). However, in patients with TJR, the bacteria could potentially localise on the prosthesis and lead to infection. There have been several case reports of infections in prosthetic hips secondary to dental treatment and the authors have emphasised the importance of providing preoperative, prophylactic antibiotic cover for patients who have had a TJR (Wilson et al., 1975; Rubin et al., 1976; Schurman et al., 1976; Cruess et al., 1985). Rubin et al. (1976) reported three cases in which there was a worrying association between dental treatment and an infected THR. The patients had long asymptomatic intervals subsequent to implantation of prosthetic hip joints. However, after dental procedures, which included root canal treatment and extractions, infections occurred in these hips. The authors pointed out that there was no proof that the three infected cases were caused by dental treatment, but there was strong circumstantial evidence linking the two. They recommended antibiotic cover for dental work in all patients with THR. Cruess et al. (1975) reported one case of metastatic infection of a THR which was associated with a dental extraction and Wilson et al. (1975) described two cases associated with dental treatment. Schurman et al. (1976) reported a case in which
Prophylactic Table 3- Aetiologic bacteria in haematogenously infected total hip replacements thought to bc of dental origin, reported in the literature (1975-80) 8-haemolytic
streptococcus cases
Staph. aureris
2 3 I
1 2 _
1 1 No growth
1
1
_
1
1
-
_
i
-
-
1
2 1
1 -
1
_
1
_
No. of -.. Wilson et al., 1975 Rubin et al., 1976 Cruess et al., 1975 Schurman* er al., 1976 Jacobsen & Murray, 1980 Downes, 1977 Stinchfield et al., 1980 Brand, 1975
*
Total
knee
joint
-~
..--_
Group
--G
Group
.-_
B
-
replacement.
bilateral knee infections occurred in a patient after TJR in both knees probably as a result of haematogenous spread from a dental abscess. Of the reported cases showing an association between dental procedures and infection in prosthetic joints, five involved streptococci and six staphylococci (Table 3). A more recent study analysed the medical and dental reports of over 2000 patients in which total prosthetic joints had been placed. The aim of this study was to determine the causal relationship between dental treatment and later prosthetic joint infections and to identify any systemic conditions that may predispose patients to them (Jacobsen et al., 1986). Of 30 (1.1%) prosthetic joint infections that occurred 6 months or more after placement, only one could be temporally associated with dental treatment. This particular patient underwent extraction of seven periodontally involved teeth and bilateral tuberosity reduction. The authors pointed out that prolonged healing of the extraction sites probably resulted in a chronic bacteraemia as well as the transient bacteraemia which occurred initially. No blood, urine or oral cultures were collected from this patient who had to undergo surgery for the prosthesis to be removed. Therefore, confirmation of a micro-organism spreading via a haematogenous route from the mouth was not possible. Interestingly, this patient also suffered from insulin-controlled diabetes and had undergone sigmoidoscopy in the period prior to infection of the THR. Nine of the 30 later infections reported in this study occurred in insulin-dependent patients and patients on longterm immunosuppressive therapy (Jacobsen et al., 1986). A computer simulation model has been used to assess the risks and effects of no prophylaxis for dental patients at risk from a late prosthetic joint infection. This analysis suggested that there is a very small risk of this postoperative complication; in the order of 29 to 68 cases per 10h dental visits (Jacobsen et al., 1988). However, the results of this must be
antibiotics
for patients
with artificial
joints
343
interpreted with care as certain assumptions were made which might not be valid in clinical practice. Metastatic infection from a bacteraemia induced by dental manipulation remains a possibility. The risks and effects of an infected hip prosthesis must be weighed against the incidence and severity of antibiotic side-effects together with the efficacy of prophylactic cover for the dental procedures. The incidence and severity of antibiotic side-effects
The relative risks of joint infection, which may result from patients not being given prophylactic antibiotic cover for dental procedures, must be weighed against the risk of untoward reactions to drug therapy. The most likely adverse reactions to antibiotics are gastrointestinal or immunological in nature. Immunological reactions range from mild to severe and may, in a few cases, result in fatal anaphylaxis. A range of estimates about the incidence of mild, severe and fatal reactions to oral penicillin can be obtained from large-scale studies of oral penicillin prophylaxis against streptococcal infections (Idsoe et al., 1968; Rudolph & Price, 1973) and clinical studies of oral cephalexin (Bannon et al., 1982; Burt, 1983). Jacobsen et al. (1988) used this data for their computer simulation model to assess the risks of no prophylaxis, oral penicillin, and oral cephalexin regimes for dental patients at risk from late prosthetic joint infections. The results of this computer model analysis seem to suggest that there is a small risk of joint infection which is outweighed by a greater risk from a fatal antibiotic reaction. Another drug-related problem associated with a blanket recommendation for prophylaxis in TJR patients is that of bacterial resistance to antibiotics. The emergence of drug resistant bacteria is now a major problem in antibiotic therapy; the frequency of this depending on the organisms and antibiotic concerned (Sleigh & Timbury, 1981). Staph. aureus which has often been implicated in prosthetic joint infections can acquire resistance to antibiotics such as penicillin. The widespread, often indiscriminate use of prophylactic antibiotics for surgical procedures has favoured the survival and increase of drug-resistant bacteria. Thus, the indiscriminate use of prophylaxis is not to be recommended. The efficacy of prophylactic antibiotic cover for dental procedures
For prophylaxis to be effective the antibiotic of choice must be given at the right time and in the correct dosage. It must also be active against the most likely infecting organisms. Burke (1961) has shown experimentally that the ability of systemic antibiotics to prevent development of a primary bacterial lesion is confined to the first 3 h after inoculation of the wound. Antibiotics should therefore be in the tissue before the bacteria are introduced. Pollard et al. (1979) was also able to
344
Fig.
British
1-
Journal
of Oral
Suggested prophylactic
and Maxillofacial antibiotic
Surgery
regime for patients with TJK undergoing
Patient
Give 1 g ccphradine orally l-1.5 h prcopcrativcly
Give
lg cephradinc at induction
N.R. Patients who have been given clindamvcin * Clindamycin tablets should& swallowedwith
I.V.
procedures
‘at risk’
Give 6tMJmg clindamycin orally I h preoperativcly’
must be advised to report if diarrhoca a glass of water.
demonstrate that a three dose regime of cephalosporin was as effective as a 2 week course of flucloxacillin in preventing infections in patients undergoing hip replacement. The duration of prophylactic cover should be kept short to minimise the selection of resistant bacteria. Gram-positive bacteria, such as Staph. aureus, Staph. epidermidis and beta-haemolytic streptococci have been particularly implicated in late infections associated with Therefore, an effective total hip replacements. prophylactic antibiotic, if used, must have bactericidal activity against most gram-positive cocci, and penicillinasenon-penicillinase including producing staphylococci, as well as some gramnegative organisms, such as Escherichia co/i and Pseudomonas species. The cephalosporins have now been established as the pre-operative and peri-operative antibiotics of choice for total joint replacement surgery (Burnett et al., 1980; Poss et al., 1984) and clindamycin has been recommended for those patients who are allergic to penicillin (Poss et al., 1984). If the decision is made to give prophylactic antibiotics to a TJR patient undergoing dental treatment, then it would seem sensible to give them a cephalosporin or alternatively clindamycin, if allergy to penicillin is reported. Prophylaxis should be given preoperatively so that therapeutic levels are reached at the time of maximum bacteraemia. Cephaloridine is acid stable, does not need to be taken on an empty stomach and achieves high bone-level concentrations. Both cephaloridine and clindamycin are available in the Dental Practitioners’ Formulary and should be given 1 to 1.5 h prior to dental treatment as a single dose (Table 4). Unfortunately, clindamycin has gained a bad reputation because of its potential ability to cause pseudomembranous colitis, which can be particularly dangerous and debilitating in older patients. This condition has never been reported following a single dose of clindamycin. Clindamycin has now been recommended as an alternative to erythromycin for prophylaxis against infective endocarditis in dental patients who are allergic to penicillin (Working Party of the British Society for Antimicrobial Chemotherapy, 1990). Suggested oral prophylactic regimes for TJR patients undergoing dental procedures are shown in Table 4.
likely to produce a bactcraemia.
Give
600 mg clindamycin I.V. at induction
dcvclops.
CONCLUSIONS
There is widespread controversy concerning the justification of systematic antimicrobial prophylaxis for dental patients with prosthetic joints. A number of studies have attempted to determine the causal relationship between dental procedures and late prosthetic joint infections, but have only been able to demonstrate a temporal association. There is, to date, no demonstrated case of joint infection induced by transient bacteria of dental origin. The bacteria which have been implicated in late infections of joint replacements are mainly staphylococci and beta-streptococci which have been infrequently isolated for dentally related bacteraemias and do not form a significant part of the normal oral flora. Those authorities who advocate blanket antibiotic cover for dental patients with a TJR feel that the outcome of an infected prosthesis is so devastating that any risk of antibiotic prophylaxis is far outweighed by the possible benefits. Consequently, they recommend prophylaxis prior to any dental treatment likely to induce bacteraemias and this includes extractions, scaling and any surgery involving the gingivae. It has also been recommended that a dentist should consult with the patient’s orthopaedic surgeon regarding the need for prophylaxis in each individual case. However, McGowan and Hendrey (1985) felt that this approach was often impracticable and led to irrational, fail-safe decisions. Ultimately, however, it is the dental surgeon who must make a decision concerning prophylaxis as he is legally responsible for the consequences that may ensue from subsequent dental treatment. If an official professional body responsible for dental care makes a recommendation that blanket antibiotic coverage should be used for TJR patients, then any practitioner ignoring such advice might be faced with medico-legal consequences (Eskinazi & Rathbun, 1988). Such a practitioner may have good reasons to disagree with a recommendation, which may be inappropriate in every case. Clearly, a consensus must be reached and recommendations made for the dental treatment of patients with a TJR. Liaison between the dental profession and their orthopaedic colleagues remains appropriate in these
Prophylactic
cases, but should be initiated whenever possible before patients undergo surgery for total joint replacement. These individuals should be rendered dentally fit prior to orthopaedic surgery and any possible sources of dental sepsis eliminated before the operation. Oral hygiene instruction should be given to all dentate patients and the possible consequences of dental neglect emphasised. Orthopaedic surgeons must inform patients undergoing TJR of the need for antibiotic prophylaxis for dental treatment if they feel that this is appropriate. This information should also be conveyed directly to the patient’s dental practitioner at the time of discharge from hospital. Certain groups have been identified as being particularly at risk from late joint infections and include patients with rheumatoid arthritis and those who have had previous complications with joint replacement, particularly infections. Data would also suggest that long term immunosuppression and systemic conditions such as insulin-dependent diabetes may predispose patients to late prosthetic joint infections during dental trcatmcnt likely to induce bacteraemias (Jacobsen etul., 1986). It would be erttirely justifiable to recommend antibiotic prophylaxis for such individuals with a TJR. Unfortunately, a number of TJR patients may present in pain and request emergency dental treatment from a dental practice that they have not previously attended. If they have not been advised about the need for antibiotic prophylaxis for dental procedures then this presents the dental surgeon with a dilemma: whether to give antibiotic cover or not? Consultation with the patient’s orthopaedic surgeon is often impracticable and in these circumstances a preventive regime would also seem entirely reasonable. Patients presenting in pain frequently require extraction or drainage of a dental abscess and this provides further justification for what might be considered by some authorities as a fail-safe decision. Prophylactic antibiotics, if given, should be administered preoperatively and in adequate doses. The cephalosporins are the drugs of choice in patients not allergic to penicillin (Table 4). Attempts should always be made to reduce the level of bacteraemias during dental treatment in all patients but this is particularly important in individuals who have undergone TJR, whether or not they receive antibiotic cover. Pre-operative irrigation of the gingival crevice and mouth rinsing with a chlorhexidine solution has been shown to reduce the level of bacteraemia foliowing extractions (MacFarlane et al., 1984) and also appears to reduce the incidence of ‘dry socket’ postoperatively (Field et al., 1988). Patients should be given a chlorhexidine mouthrinse prior to any form of interventive dental treatment that may produce a bacteraemia. If an acute infection develops in a patient who has undergone TJR then antibiotic therapy must be instituted immediately, together with any necessary surgical procedures. Pus samples should be collected as soon as possible and the antibiotic may need to be
antibiotics
for patients
with
artificial
joints
345
changed substantially, depending on the results of culture and sensitivity. An interdisciplinary approach to the problems associated with dental patients who have undergone TJR is essential and the decision of whether to give prophylaxis or not must be made after careful consideration of the risks and benefits in each individual case. Clearly, this dilemma will not disappear, and as the number of operations for joint replacements rises an increasing number of this patient group will retain part of their natural dentition and seek dental treatment. Acknowledgements The authors would like to thank Professor Lesley Klenerman, Department of Orthopaedic Surgery, University of Liverpool, for his advice and encouragement and Mrs C. Munro who typed the paper.
References Bannon. J. A., Foradori. G. T. & Schrogie. J. J. (!YX2). The USC of cefadoxil suspension in children. Journal o,fAntimicrohiul
Chemotherupy.
10. 153.
Blomgren, G. (lY81) Haematogcnous infection of total joint replacement. Acru Orrhopuedicu Scundinuvicu. 52. (Supplement 187). Brand. R. A. (1975). Late haematogcnous infection in total joint replacement. Journal of lowu MediculSociety. L5.3%?. Burke, J. F. (1961). The effective period of preventive antibiotic action in experimental incisions and dcrmal lesions. Surgery.
50,161. Burnett, J. W.. Gustilo, R. B.. Williams. D. N. & Kind, A. C. (1980). Prophylactic antibiotics in hip fractures. The Journal
of Bone and Joint Surgery. 62A. 457. Burt, R. A. (1983). A review of the drug events reported by 12,Y17 patients treated with cephalexin. Posrgruduare
Medical Journul. 59.47. Cioffi, G. A.. Tcrczhalmy. G. ‘I‘. & Taybos. G. M. ( 1988). Total joint replacement: A consideration for antimicrobial prophylaxis. Oral Surgery, Orul Medicine, Orul Pu/hology.
66. 124. Cruess. R. L., Bickel. W. S. B Von Kcsslcr. K. L. (lY7.5). Infections in total hips secondary to a primary source elsewhere. Clinicul Orrhopuedics. 106. 2YY. Downes. E. M. (1977). Late infection after total hip rcplaccment.
The Journal of Bone and Joint Surgery, 59B. 42. Eskinazi, I>. & Rathhun, W. (1988). Is systemic antimicrobial prophylaxis justified in dental patients with prosthetic joints? (Editorial) Oral Surgery. Oral Medicine. Oral Pathology, 66.
430. Field, E. A.. Nind. D., Varga. E. & Martin. M. V. (198X). The effect of chlorhexidinc irrigation on the incidence of dry socket: a pilot studv. Rrirish Journul of Oral uqd MuxilloFacial S&,gery .26,3Y5. IJischmann. M. D. (1984). Antibiotics in the nrevcntion of . infection associated with prosthetic devices. In: Infections Assoriuted wirh Prosrheric Devices, H. Sugarman (ed.). pp. 269-78. Florida: C.R.C. Press. Hori; R. Y.. Lewis, J. I.., Zimmerman. J. R. & Compere. C. L. (lY78). The number of total joint replacemcn!s in the tJ.S.
Clinicul Orrhopuedics.
132. 46.
Idsoe. 0.. Guthc. T., Willcox, R. & DcWcck. A. (106X). Nature and cxtcnt of penicillin sidc-rcactions with particular rcfcrcncc to fatalities from anaphylactic shock. Bulle/in of rhe World Healrh Orgunisution,38. 159. Jacobsen, P. L. & Murray, W. (1980) Prophylactic coverage of dental patients with artificial joint; a retrospective analysis of thirtv-three infections in hip prosthcscs. Orul Surgery. Orul
Medkne.
0ruI Purhology. ‘so. 130.
Jacobsen. J. J.. Millard. 11. D.. Plczia, R. & KSlank.cnship. J. R (IYS6). Dental treatment and late prosthetic joint infections. Oral Surgery, Orul Medicine, Orul Pathology 61.4 13.
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Jacobsen, J. J.. Schweitzer, S.. De Porter. D. J. & Lee. J. J. (19X8). Chemoprophylaxis of dental patients with prosthetic joints: a simulation model. Journalof Denrul Educafion. 52.
599. Jaspcrs. M. T. & Little, J. W. (1985). Prophylactic antibiotic coverage in patients with total arthroplasty: current practice. Journal ofthe Americun Dental Association. 11 I. 943. Klencrman. L. (1984). The managcmcnt of the infected endoprosthesis. The Journal of Bone and Joinr Surgery, 66B.
644.5. MacFariane. T. W.. Ferguson. M. M. & Mulgrcw C. J. (1984). Post-extraction bactcracmia: role of antiseptics and antibiotics. British DentalJournal, 156. 179. McGowan, D. A. & Hcndrcy, M. L. (1985). lsantibioiic prophylaxis required for dental patients with joint replacements:’ British Dental Journal. 158, 336. Mulligan, R. (1980). Late infections in patients with prostheses for total hip rcplaccmcnt of joints: implications for the dental practitioner. Journal of rhe American Denial A.ssociuiion.
101.44. Office of Health Economics (1982). Hip replacement and the N.1I.S. Currenr Health Problems, No. 171, London. Peterson. L. J. (19X0). Prosthetic joint infection and dental procedures (Letter). Journal of the American Dentul
Associulion. 101,598. Pollard, J. P.. Hughes. S. P. F.. Scott, J. E., Evans, M. J. & Benson. M. K. D. (1979). Antibiotic prophylaxis in total hip replacement. British MediculJournal. 1.7@. Poss. R.. Thornhill. M. S.. Edward, F. C.. Thomas, W. H., Battle, N. J. & Slcdgc. C. B. (1984). Factors inlluencing the incidence and outcome of infection following total joint arthroplasty. Clinical Orrhopaedics, 182, 117. Rubin. R.. Salvati, A. & Lewis, R. (1976). Infected total hip replacement after dental procedures. Journal ofOral
Infeclions Associufed with Prosthetic Devices. B. Sugarman (ed.). pp. 181-218. Florida: C.R.C. Press. Schurman, D. J., Aptcrar. R. G. & Burten, D. S. (1976). Infection in total knee joint replacement, secondary to tooth abscess. Western Journal of Medicine, 125.226. Shay. K. & Lloyd. P. M. (1988). Dental schools’ practicesof prophylactic antibiotic coverage for patients with prosthetic joints. Journal of Dentul Education, 52,564. Sleigh, J. D. & Timbury, M. C. (1981). Nores on Medical Microbiology, p. 323. Edinburgh 6t London: Churchill Livingstonc. Stinchfield. F. E.. Bigliani, L. U., Neu, H. C.. Goss. T. P. & Foster, C. R. (1980). Late haematogenous infection of total joint replacement. The Journol of Bone and Joinr Surgery.
62A, 3345. Wilson, P. D.. Salvati. E. A. & Blumenfield. E. L. (1975). The problem of infection in total prosthetic arthroplasty of the hip. Surgicul Clinics of North America. 55, 1431. Working Party of the British Society for Antimicrobial Chemotherapy (1990). Prophylaxis of infective endocarditis. Lancef. 1. 88.
The Authors E. A. Field BDS, MDS, FDSRCS Lecturer in Oral Medicine M. V. Martin BDS, BA, PhD, MRCPath Senior Lecturer in Oral Microbiology Department of Clinical Dental Sciences University of Liverpool Pembroke Place Liverpool IA9 3BX
Surgery, 41. 18. Rudolph, A. & Price, E. (1973). Penicillin reactions among patients in venereal disease clinics: a national survey. Journal
Correspondence
and requests for offprints to Mrs E. A. Field
of the American Medical Associution, 223,499. Salvati. E. A., Small, R. D., Brause, M. D. & Pelt&i. M.D. (1984). Infections associated with orthopaedic devices. In:
Paper received 29 January Accepted 4 March 1991
1991
oral
E. A. Field, M. V. Martin Department
of Clinical Dental Sciences,
-
~..
University of Liverpool, ~..
.-
Liverpool
..~
SUMMARY. Prophylactic antibiotic cover for certain oral and dental procedures for patients with artificial joints is a controversial issue. This paper examines the evidence supporting the use of antibiotic cover and concludes that routinely, for the majority of patients with artificial joints, it is not justified. Certain medically compromised patients with artificial joints have a slightly increased risk of infection and, under these circumstances, antibiotic prophylaxis may be justified. The antibiotic recommended for this group is cephradine or in the case of penicillin allergy, clindamycin. Preoperative dental fitness is mandatory for all patients who are to receive artificial joints. This information will be of interest to the oral and maxillofacial surgeon in his own clinical practice, and when giving advice to local general dental practitioners.
INTRdDUCTION
known to cause transient or prolonged bacteracmias have also been implicated in infections of TJR (Blomgren, 1981; Cioffi et al., 1988).
Replacement of severely damaged joints with artificial prostheses is one of the major post-war surgical developments. Of all forms of joint replacement, that for hips represents the most outstanding innovation. Total hip replacement (THR) is an example of a technique that can radically improve the quality of life at an acceptably low cost (Office of Health Economics, 1982). Data for 1978 showed that there were about 28O@l THR operations carried out in NHS hospitals in England and Wales (Office of Health Economics, 1982) and 25OOOt.lcarried out throughout the world every year (Hori et al., 1978). The next most frequent total joint replacement (TJR) is arthroplasty of the knee, but this is technically more difficult and the failure rate higher. Other joints replaced have included the shoulder, ankle, wrist, finger, elbow and temporomandibular joints, but all to a lesser degree than the hip joint. Total hip replacement is undertaken mainly for cases of degenerative joint disease (osteoarthritis) and, to a lesser extent, for rheumatoid arthritis.
The consequences
of an infected hip replacement
Deep infection of a THR invariably leads to loosening of the prosthetic components and this usually neccssitates removal followed by an exchange arthroplasty, if possible. Alternatively, the components are removed leaving a pseudoarthrosis which results in large skeletal defects, shortening of the limb and disastrous physical impairment (Salvati, 1984). Failure to satisfactorily manage an infected hip replacement may result in a chronic, persistent osteomyelitis and possible hind quarter amputation or death (Klenerman, 1984). Such infection, therefore, carries an enormous crippling morbidity and the additional burden of increased health-care costs for hospitalisation and rehabilitation (Salvati, 1984). The majority of orthopacdic surgeons who must deal with the potentially devastating consequences of an infected joint replacement now recommend antibiotic prophylaxis for dental patients with a TJR (Stinchfield et al., 1980; Jaspers & Little, 1985; Shay & Lloyd, 1988). Klenerman (1984), in a paper on the infected cndoprosthcsis, advised that patients with total hip replacement must bc warned of the possible implications of intercurrent infections, dental extractions and urinary tract operations and felt that dental surgeons should bc alert to the necessity for broad spectrum antibiotic cover in these situations. Paradoxically, one survey has shown that of those orthopaedic surgeons who responded, the majority advised a prophylactic antibiotic regime for dental patients with a TJR, although they considered that
Infection of artificial joints
The most serious complication of TJR is infection (Mulligan, 1980) and this occurs either at the time of operation or from haematogcnous spread from distant foci of infection. Infection of an endoprosthesis may appear shortly after the replacement or months or years after an apparently benign postoperative period. Later infections are usually caused by micro-organisms which have remained latent since the time of operation or have metastasised from other infected sites (for example, skin, respiratory or urinary tracts). Certain dental procedures 341
342
British
Journal
of Oral
and Maxillofacial
Surgery
there was either no relationship, or a minor one, between dentally-induced transient hacteraemias and later prosthetic joint infections (Jaspers & Little, 1985). Bone cements impregnated with gentamicin also help to prevent deep sepsis postoperatively, but there is evidence from animal studies that antibiotic-loaded acrylic cements do not provide protection against later haematogenous infections (Klenerman, 1984). Haematogenous
infection of the THR
Improved surgical techniques at the time of the operation have greatly decreased the incidence of early infections in THR but late infections still present a problem. These are mainly thought to be caused by bacteria of haematogenous origin. Experimental haematogenous infection of total joint prostheses has been produced in experimental animals using a strain of Staphylococcus aureus. Blomgren (1981) induced bacteraemia in rabbits, which had human finger joint prostheses cemented in both knees, 6 to 8 weeks postoperatively. A third of the joints become infected with Staph. aureus after 25 days. However, over half the experimental animals died and the bacterial inoculation was probably large enough to represent a scpticaemia, rather than a transient bacteraemia which commonly arises in patients undergoing oral and dental procedures (Hirschmann, 1984). Several case reports and papers have given accounts of late infections of THR secondary to distant foci of infection and these have been collected and analysed by Biomgren (1981). Table 1 summarises the bacterial findings in these cases and Table 2 lists the primary foci of infection in the cases that Blomgren found reported in the literature. There does not seem to be a time limit to the period that a patient is at risk from haematogenous spread and infections have been reported to occur up to 5 years after TJR (Mulligan, 1980). The TJR is at risk from bacteraemia because the cement which holds the endoprosthesis in place reduces the vascu1- Aetiologic bacteria in 61 hacmatogenously infected total hip replacements (57 patients) reported in the literature lY7>XfJ (Blomgren, lY81)
Table
Frequency Bacteria Sraplryl0coccu.s P-Streptococci Pncumococci
Number amens
Staphylococcus epidermidis Escherichia coli Proteus mirubilis
W)
28 9 5
46 15 8
s
8
4
8
4
7
Pseudomonads
I
7
Mycohacrerium ruherculosiv Salmonella ryphimurium Viridans sveptococci and Prowus mirahilis Bacreroides frugilis Aeromonas hydrophiliu
I
1 1 1 1
Table 2 - Primary foci of infection in 61 haematogenously infected total hip replacements in the literature 1973-W (Hlomgren, Primary
1981)
foci
Respiratory tract Dermal Urinary tract Dental Castro-enteric tract Otitis media Parotitis Unknown
Number 11 10 9 7 4 1 I I4
larity and infection tends to develop at the interface of the bone and prosthesis. Data from a number of studies has shown that patients with rheumatoid arthritis are particularly susceptible to late infection after TJR because of their altered immune response and general debilitation (Peterson, 1980; Poss et al., 1984; Cioffi et al., 1988). The incidence of deep sepsis following THR is also significantly increased if the patient has had a previous hip operation or has undergone revision surgery for previous failure (Poss et ftf., 1984). The risk of haematogenous dental procedures
spread from oral and
Many oral and dental procedures produce a transient bacteraemia. These include extractions, scaling, oral and periodontal surgery and drainage of abscesses. Such procedures usually produce a bacteraemia which is small in quantity, asymptomatic and short lived (Hirschmann, 1984). However, in patients with TJR, the bacteria could potentially localise on the prosthesis and lead to infection. There have been several case reports of infections in prosthetic hips secondary to dental treatment and the authors have emphasised the importance of providing preoperative, prophylactic antibiotic cover for patients who have had a TJR (Wilson et al., 1975; Rubin et al., 1976; Schurman et al., 1976; Cruess et al., 1985). Rubin et al. (1976) reported three cases in which there was a worrying association between dental treatment and an infected THR. The patients had long asymptomatic intervals subsequent to implantation of prosthetic hip joints. However, after dental procedures, which included root canal treatment and extractions, infections occurred in these hips. The authors pointed out that there was no proof that the three infected cases were caused by dental treatment, but there was strong circumstantial evidence linking the two. They recommended antibiotic cover for dental work in all patients with THR. Cruess et al. (1975) reported one case of metastatic infection of a THR which was associated with a dental extraction and Wilson et al. (1975) described two cases associated with dental treatment. Schurman et al. (1976) reported a case in which
Prophylactic Table 3- Aetiologic bacteria in haematogenously infected total hip replacements thought to bc of dental origin, reported in the literature (1975-80) 8-haemolytic
streptococcus cases
Staph. aureris
2 3 I
1 2 _
1 1 No growth
1
1
_
1
1
-
_
i
-
-
1
2 1
1 -
1
_
1
_
No. of -.. Wilson et al., 1975 Rubin et al., 1976 Cruess et al., 1975 Schurman* er al., 1976 Jacobsen & Murray, 1980 Downes, 1977 Stinchfield et al., 1980 Brand, 1975
*
Total
knee
joint
-~
..--_
Group
--G
Group
.-_
B
-
replacement.
bilateral knee infections occurred in a patient after TJR in both knees probably as a result of haematogenous spread from a dental abscess. Of the reported cases showing an association between dental procedures and infection in prosthetic joints, five involved streptococci and six staphylococci (Table 3). A more recent study analysed the medical and dental reports of over 2000 patients in which total prosthetic joints had been placed. The aim of this study was to determine the causal relationship between dental treatment and later prosthetic joint infections and to identify any systemic conditions that may predispose patients to them (Jacobsen et al., 1986). Of 30 (1.1%) prosthetic joint infections that occurred 6 months or more after placement, only one could be temporally associated with dental treatment. This particular patient underwent extraction of seven periodontally involved teeth and bilateral tuberosity reduction. The authors pointed out that prolonged healing of the extraction sites probably resulted in a chronic bacteraemia as well as the transient bacteraemia which occurred initially. No blood, urine or oral cultures were collected from this patient who had to undergo surgery for the prosthesis to be removed. Therefore, confirmation of a micro-organism spreading via a haematogenous route from the mouth was not possible. Interestingly, this patient also suffered from insulin-controlled diabetes and had undergone sigmoidoscopy in the period prior to infection of the THR. Nine of the 30 later infections reported in this study occurred in insulin-dependent patients and patients on longterm immunosuppressive therapy (Jacobsen et al., 1986). A computer simulation model has been used to assess the risks and effects of no prophylaxis for dental patients at risk from a late prosthetic joint infection. This analysis suggested that there is a very small risk of this postoperative complication; in the order of 29 to 68 cases per 10h dental visits (Jacobsen et al., 1988). However, the results of this must be
antibiotics
for patients
with artificial
joints
343
interpreted with care as certain assumptions were made which might not be valid in clinical practice. Metastatic infection from a bacteraemia induced by dental manipulation remains a possibility. The risks and effects of an infected hip prosthesis must be weighed against the incidence and severity of antibiotic side-effects together with the efficacy of prophylactic cover for the dental procedures. The incidence and severity of antibiotic side-effects
The relative risks of joint infection, which may result from patients not being given prophylactic antibiotic cover for dental procedures, must be weighed against the risk of untoward reactions to drug therapy. The most likely adverse reactions to antibiotics are gastrointestinal or immunological in nature. Immunological reactions range from mild to severe and may, in a few cases, result in fatal anaphylaxis. A range of estimates about the incidence of mild, severe and fatal reactions to oral penicillin can be obtained from large-scale studies of oral penicillin prophylaxis against streptococcal infections (Idsoe et al., 1968; Rudolph & Price, 1973) and clinical studies of oral cephalexin (Bannon et al., 1982; Burt, 1983). Jacobsen et al. (1988) used this data for their computer simulation model to assess the risks of no prophylaxis, oral penicillin, and oral cephalexin regimes for dental patients at risk from late prosthetic joint infections. The results of this computer model analysis seem to suggest that there is a small risk of joint infection which is outweighed by a greater risk from a fatal antibiotic reaction. Another drug-related problem associated with a blanket recommendation for prophylaxis in TJR patients is that of bacterial resistance to antibiotics. The emergence of drug resistant bacteria is now a major problem in antibiotic therapy; the frequency of this depending on the organisms and antibiotic concerned (Sleigh & Timbury, 1981). Staph. aureus which has often been implicated in prosthetic joint infections can acquire resistance to antibiotics such as penicillin. The widespread, often indiscriminate use of prophylactic antibiotics for surgical procedures has favoured the survival and increase of drug-resistant bacteria. Thus, the indiscriminate use of prophylaxis is not to be recommended. The efficacy of prophylactic antibiotic cover for dental procedures
For prophylaxis to be effective the antibiotic of choice must be given at the right time and in the correct dosage. It must also be active against the most likely infecting organisms. Burke (1961) has shown experimentally that the ability of systemic antibiotics to prevent development of a primary bacterial lesion is confined to the first 3 h after inoculation of the wound. Antibiotics should therefore be in the tissue before the bacteria are introduced. Pollard et al. (1979) was also able to
344
Fig.
British
1-
Journal
of Oral
Suggested prophylactic
and Maxillofacial antibiotic
Surgery
regime for patients with TJK undergoing
Patient
Give 1 g ccphradine orally l-1.5 h prcopcrativcly
Give
lg cephradinc at induction
N.R. Patients who have been given clindamvcin * Clindamycin tablets should& swallowedwith
I.V.
procedures
‘at risk’
Give 6tMJmg clindamycin orally I h preoperativcly’
must be advised to report if diarrhoca a glass of water.
demonstrate that a three dose regime of cephalosporin was as effective as a 2 week course of flucloxacillin in preventing infections in patients undergoing hip replacement. The duration of prophylactic cover should be kept short to minimise the selection of resistant bacteria. Gram-positive bacteria, such as Staph. aureus, Staph. epidermidis and beta-haemolytic streptococci have been particularly implicated in late infections associated with Therefore, an effective total hip replacements. prophylactic antibiotic, if used, must have bactericidal activity against most gram-positive cocci, and penicillinasenon-penicillinase including producing staphylococci, as well as some gramnegative organisms, such as Escherichia co/i and Pseudomonas species. The cephalosporins have now been established as the pre-operative and peri-operative antibiotics of choice for total joint replacement surgery (Burnett et al., 1980; Poss et al., 1984) and clindamycin has been recommended for those patients who are allergic to penicillin (Poss et al., 1984). If the decision is made to give prophylactic antibiotics to a TJR patient undergoing dental treatment, then it would seem sensible to give them a cephalosporin or alternatively clindamycin, if allergy to penicillin is reported. Prophylaxis should be given preoperatively so that therapeutic levels are reached at the time of maximum bacteraemia. Cephaloridine is acid stable, does not need to be taken on an empty stomach and achieves high bone-level concentrations. Both cephaloridine and clindamycin are available in the Dental Practitioners’ Formulary and should be given 1 to 1.5 h prior to dental treatment as a single dose (Table 4). Unfortunately, clindamycin has gained a bad reputation because of its potential ability to cause pseudomembranous colitis, which can be particularly dangerous and debilitating in older patients. This condition has never been reported following a single dose of clindamycin. Clindamycin has now been recommended as an alternative to erythromycin for prophylaxis against infective endocarditis in dental patients who are allergic to penicillin (Working Party of the British Society for Antimicrobial Chemotherapy, 1990). Suggested oral prophylactic regimes for TJR patients undergoing dental procedures are shown in Table 4.
likely to produce a bactcraemia.
Give
600 mg clindamycin I.V. at induction
dcvclops.
CONCLUSIONS
There is widespread controversy concerning the justification of systematic antimicrobial prophylaxis for dental patients with prosthetic joints. A number of studies have attempted to determine the causal relationship between dental procedures and late prosthetic joint infections, but have only been able to demonstrate a temporal association. There is, to date, no demonstrated case of joint infection induced by transient bacteria of dental origin. The bacteria which have been implicated in late infections of joint replacements are mainly staphylococci and beta-streptococci which have been infrequently isolated for dentally related bacteraemias and do not form a significant part of the normal oral flora. Those authorities who advocate blanket antibiotic cover for dental patients with a TJR feel that the outcome of an infected prosthesis is so devastating that any risk of antibiotic prophylaxis is far outweighed by the possible benefits. Consequently, they recommend prophylaxis prior to any dental treatment likely to induce bacteraemias and this includes extractions, scaling and any surgery involving the gingivae. It has also been recommended that a dentist should consult with the patient’s orthopaedic surgeon regarding the need for prophylaxis in each individual case. However, McGowan and Hendrey (1985) felt that this approach was often impracticable and led to irrational, fail-safe decisions. Ultimately, however, it is the dental surgeon who must make a decision concerning prophylaxis as he is legally responsible for the consequences that may ensue from subsequent dental treatment. If an official professional body responsible for dental care makes a recommendation that blanket antibiotic coverage should be used for TJR patients, then any practitioner ignoring such advice might be faced with medico-legal consequences (Eskinazi & Rathbun, 1988). Such a practitioner may have good reasons to disagree with a recommendation, which may be inappropriate in every case. Clearly, a consensus must be reached and recommendations made for the dental treatment of patients with a TJR. Liaison between the dental profession and their orthopaedic colleagues remains appropriate in these
Prophylactic
cases, but should be initiated whenever possible before patients undergo surgery for total joint replacement. These individuals should be rendered dentally fit prior to orthopaedic surgery and any possible sources of dental sepsis eliminated before the operation. Oral hygiene instruction should be given to all dentate patients and the possible consequences of dental neglect emphasised. Orthopaedic surgeons must inform patients undergoing TJR of the need for antibiotic prophylaxis for dental treatment if they feel that this is appropriate. This information should also be conveyed directly to the patient’s dental practitioner at the time of discharge from hospital. Certain groups have been identified as being particularly at risk from late joint infections and include patients with rheumatoid arthritis and those who have had previous complications with joint replacement, particularly infections. Data would also suggest that long term immunosuppression and systemic conditions such as insulin-dependent diabetes may predispose patients to late prosthetic joint infections during dental trcatmcnt likely to induce bacteraemias (Jacobsen etul., 1986). It would be erttirely justifiable to recommend antibiotic prophylaxis for such individuals with a TJR. Unfortunately, a number of TJR patients may present in pain and request emergency dental treatment from a dental practice that they have not previously attended. If they have not been advised about the need for antibiotic prophylaxis for dental procedures then this presents the dental surgeon with a dilemma: whether to give antibiotic cover or not? Consultation with the patient’s orthopaedic surgeon is often impracticable and in these circumstances a preventive regime would also seem entirely reasonable. Patients presenting in pain frequently require extraction or drainage of a dental abscess and this provides further justification for what might be considered by some authorities as a fail-safe decision. Prophylactic antibiotics, if given, should be administered preoperatively and in adequate doses. The cephalosporins are the drugs of choice in patients not allergic to penicillin (Table 4). Attempts should always be made to reduce the level of bacteraemias during dental treatment in all patients but this is particularly important in individuals who have undergone TJR, whether or not they receive antibiotic cover. Pre-operative irrigation of the gingival crevice and mouth rinsing with a chlorhexidine solution has been shown to reduce the level of bacteraemia foliowing extractions (MacFarlane et al., 1984) and also appears to reduce the incidence of ‘dry socket’ postoperatively (Field et al., 1988). Patients should be given a chlorhexidine mouthrinse prior to any form of interventive dental treatment that may produce a bacteraemia. If an acute infection develops in a patient who has undergone TJR then antibiotic therapy must be instituted immediately, together with any necessary surgical procedures. Pus samples should be collected as soon as possible and the antibiotic may need to be
antibiotics
for patients
with
artificial
joints
345
changed substantially, depending on the results of culture and sensitivity. An interdisciplinary approach to the problems associated with dental patients who have undergone TJR is essential and the decision of whether to give prophylaxis or not must be made after careful consideration of the risks and benefits in each individual case. Clearly, this dilemma will not disappear, and as the number of operations for joint replacements rises an increasing number of this patient group will retain part of their natural dentition and seek dental treatment. Acknowledgements The authors would like to thank Professor Lesley Klenerman, Department of Orthopaedic Surgery, University of Liverpool, for his advice and encouragement and Mrs C. Munro who typed the paper.
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430. Field, E. A.. Nind. D., Varga. E. & Martin. M. V. (198X). The effect of chlorhexidinc irrigation on the incidence of dry socket: a pilot studv. Rrirish Journul of Oral uqd MuxilloFacial S&,gery .26,3Y5. IJischmann. M. D. (1984). Antibiotics in the nrevcntion of . infection associated with prosthetic devices. In: Infections Assoriuted wirh Prosrheric Devices, H. Sugarman (ed.). pp. 269-78. Florida: C.R.C. Press. Hori; R. Y.. Lewis, J. I.., Zimmerman. J. R. & Compere. C. L. (lY78). The number of total joint replacemcn!s in the tJ.S.
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644.5. MacFariane. T. W.. Ferguson. M. M. & Mulgrcw C. J. (1984). Post-extraction bactcracmia: role of antiseptics and antibiotics. British DentalJournal, 156. 179. McGowan, D. A. & Hcndrcy, M. L. (1985). lsantibioiic prophylaxis required for dental patients with joint replacements:’ British Dental Journal. 158, 336. Mulligan, R. (1980). Late infections in patients with prostheses for total hip rcplaccmcnt of joints: implications for the dental practitioner. Journal of rhe American Denial A.ssociuiion.
101.44. Office of Health Economics (1982). Hip replacement and the N.1I.S. Currenr Health Problems, No. 171, London. Peterson. L. J. (19X0). Prosthetic joint infection and dental procedures (Letter). Journal of the American Dentul
Associulion. 101,598. Pollard, J. P.. Hughes. S. P. F.. Scott, J. E., Evans, M. J. & Benson. M. K. D. (1979). Antibiotic prophylaxis in total hip replacement. British MediculJournal. 1.7@. Poss. R.. Thornhill. M. S.. Edward, F. C.. Thomas, W. H., Battle, N. J. & Slcdgc. C. B. (1984). Factors inlluencing the incidence and outcome of infection following total joint arthroplasty. Clinical Orrhopaedics, 182, 117. Rubin. R.. Salvati, A. & Lewis, R. (1976). Infected total hip replacement after dental procedures. Journal ofOral
Infeclions Associufed with Prosthetic Devices. B. Sugarman (ed.). pp. 181-218. Florida: C.R.C. Press. Schurman, D. J., Aptcrar. R. G. & Burten, D. S. (1976). Infection in total knee joint replacement, secondary to tooth abscess. Western Journal of Medicine, 125.226. Shay. K. & Lloyd. P. M. (1988). Dental schools’ practicesof prophylactic antibiotic coverage for patients with prosthetic joints. Journal of Dentul Education, 52,564. Sleigh, J. D. & Timbury, M. C. (1981). Nores on Medical Microbiology, p. 323. Edinburgh 6t London: Churchill Livingstonc. Stinchfield. F. E.. Bigliani, L. U., Neu, H. C.. Goss. T. P. & Foster, C. R. (1980). Late haematogenous infection of total joint replacement. The Journol of Bone and Joinr Surgery.
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The Authors E. A. Field BDS, MDS, FDSRCS Lecturer in Oral Medicine M. V. Martin BDS, BA, PhD, MRCPath Senior Lecturer in Oral Microbiology Department of Clinical Dental Sciences University of Liverpool Pembroke Place Liverpool IA9 3BX
Surgery, 41. 18. Rudolph, A. & Price, E. (1973). Penicillin reactions among patients in venereal disease clinics: a national survey. Journal
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Paper received 29 January Accepted 4 March 1991
1991
