262
Letters to the Editor
(We thank Dr S. C. Sanyal of the Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, for confirming the identity of the organism in this case.)
Department of Microbiology, Lokmanya Tilak Municipal Medical College and Hospital, Sion, Bombay- 400 022, India
Uma M. Tendolkar Lina P. Deodhar
References 1. Baumann P, Schubert RHW. Family Vibrionaceae. In: Krieg NR, Ed. Bergey's manual of systematic bacteriology, vol. I. London: Williams and Wilkins, 1984: 516-545. 2. Parker MT, Smith G. Vibrio, Aeromonas, Plesiomonas, Campylobacter and Spirillum. In: Parker MT, Ed. Tropley and Wilson's principles of bacteriology, virology and immunity. London: Edward Arnold, 1983 : I37-I55. 3. Parke II DW, Brinton GS. Endophthalmitis. In: Tabbara KF, Hyndiuk RA, Eds. Infections of the eye. Boston: Little, Brown, 1986: 563-585. 4. Blake PA, Weaver RE, Hollis DG. Diseases of humans (other than cholera) caused by vibrios. Ann Rev Med Microbiol, 198o; 34: 341-367. 5. Schewan JM, Veron M. Genus Vibrio. In: Buchanan RE, Gibbons NE, Eds. Bergey's manual of determinative bacteriology. Baltimore: Williams and Wilkins, 1974: 340-345.
Achromobacter Group B replacement valve endocarditis Accepted for publication 29 November 1989 Sir, We wish to report a case of late replacement valve endocarditis due to Achromobacter G r o u p B, an unusual organism that has not previously been implicated as a cause of prosthetic valve endocarditis (PVE). In early October 1987, a 28-year-old m a n was found to have Streptococcus sanguis endocarditis involving a bicuspid aortic valve. Despite appropriate antibiotic therapy, the patient deteriorated with marked aortic valve regurgitation. In m i d - O c t o b e r , the aortic valve was replaced by a p u l m o n a r y autograft and a fresh p u l m o n a r y homograft was inserted. T h e post-operative course was uneventful. T h e patient returned in M a r c h I988 with a week's history of lethargy, malaise, pleuritic chest pain, sweating and exertional dyspnoea. On examination, a low-grade fever was the sole abnormality detected. A short ejection systolic m u r m u r was unchanged from the time of his original surgery. Investigations revealed a neutrophil leucocytosis ( i 3 o o o x l o G / 1 ) , raised E S R ( 5 5 m m / I h ) and C-reactive protein (85 mg/1). Chest radiographs showed an enlarged cardiac silhouette and electrocardiography revealed non-specific T - w a v e changes. Although the replacement p u l m o n a r y homograft could not be seen, M - m o d e ethocardiography did not show any evidence of autograft regurgitation or vegatations. T h r e e consecutive sets of blood cultures yielded growth of a G r a m - n e g a t i v e bacillus in all six bottles after 24 h incubation. T h e isolate was identified as Achromobacter G r o u p B. N o clinical or laboratory evidence of infection outside the cardiovascular system could be found; infective endocarditis was diagnosed. T h e organism was sensitive to aminoglycosides, cephalosporins, amoxycillin/clavulanate, ciprofloxacin, erythromycin and tetracycline but resistant to penicillins, sulphonamides, t r i m e t h o p r i m and rifampicin. Intravenous therapy with cefuroxime (1"5 g t.d.s.) and gentamicin was given for 6 weeks. Dosage of the latter was controlled by serum assays so as to give peaks of 5-1o rag/1 and troughs less than 2 rag/1. Peak and trough serum bactericidal titres were 32 and 4 respectively. T h e patient improved and remained well at review I year later.
Letters to the Editor
263
T h e presenting features of this patient, in association with repeatedly early positive blood cultures and indirect evidence of cardiac involvement without an alternative source of infection, strongly supported a clinical diagnosis of infective endocarditis. 1 PVE is conventionally divided into early ( < 4 months post-operatively) and late. T h e latter, unlike early PVE, is more likely to have a chronic presentation and involve pathogens of low virulence. Gram-negative bacilli are responsible for less than ~5 % cases and the mortality rate is lower (45 %)- Isolated reports record infection in late PVE with a wide range of Gram-negative organisms. 2'3 T h e genus Achromobacter comprises non-fermenting, peritrichous, saccharolytic Gram-negative bacilli. T h e only named, and the best known, species is Achromobacter xylosoxidans, but six other taxa (Groups A - F ) have infrequently been isolated from patients whose disease was of the type usually related to infection with late PVE organisms. 4 Although unspecified Achromobacter species were reported in one review as having been implicated in PVE, ~ the two cases referred to were of early-onset endocarditis following surgery for congenital heart disease and did not involve replacement valves. 5 Defective ethylene oxide gaseous sterilisation of the extracorporeal heart p u m p was implicated on that occasion. Although it is assumed that late infections are not acquired at the time of original surgery, they may in fact be due to organisms which lie dormant after their introduction in the operating theatre) In the case of our patient, we feel that the organism concerned was probably introduced during surgery. Investigations into various possible routes of entry were unrewarding. N o source of infection could be proven in this episode which is the first recorded case of Achromobacter G r o u p B endocarditis. (We thank Mr B. Holmes, Central Public Health Laboratory, Colindale, London for his help in identifying the organisms and Dr S. J. Eykyn, St Thomas' Hospital, London for her advice with management of the patient.)
* Princess Mary's Royal Air Force Hospital, and the t Royal Air Force Institute of Pathology and Tropical Medicine, Halton, Aylesbury, Buckinghamshire HP22 5PG, U.K.
K. P. McKinley*
T. J. Laundy* R. G. Mastertont~.
~: Address correspondence to: Squadron Leader R. G. Masterton.
References i. Dismukes WE, Karchmer AW, Buckley MJ, Austen WG, Swartz MN. Prosthetic valve endocarditis. Analysis of 38 cases. Circulation 1973 ; 48 : 365-377. 2. Moore-Gillon J, Eykyn SJ, Phillips I. Prosthetic valve endocarditis. Br Med J I983; 287: 739-741. 3. Cohen PS, Maguire JH, Weinstein L. Infective endocarditis caused by Gram-negative bacteria: a review of the literature, I945-I977. Pros Cardiovasc Dis I98o; 22: 2o5-24I. 4. Holmes B, Pinning CA, Dawson CA. A probability matrix for the identification of Gramnegative, aerobic, non-fermentative bacteria that grow on nutrient agar. J Gen Microbiol I986; x32: I827-I842. 5. Linde LM, Heins I-IL. Bacterial endocarditis following surgery for congential heart disease. New EnglJ Med ~96o; 263: 65-69.
Letters to the Editor
(We thank Dr S. C. Sanyal of the Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, for confirming the identity of the organism in this case.)
Department of Microbiology, Lokmanya Tilak Municipal Medical College and Hospital, Sion, Bombay- 400 022, India
Uma M. Tendolkar Lina P. Deodhar
References 1. Baumann P, Schubert RHW. Family Vibrionaceae. In: Krieg NR, Ed. Bergey's manual of systematic bacteriology, vol. I. London: Williams and Wilkins, 1984: 516-545. 2. Parker MT, Smith G. Vibrio, Aeromonas, Plesiomonas, Campylobacter and Spirillum. In: Parker MT, Ed. Tropley and Wilson's principles of bacteriology, virology and immunity. London: Edward Arnold, 1983 : I37-I55. 3. Parke II DW, Brinton GS. Endophthalmitis. In: Tabbara KF, Hyndiuk RA, Eds. Infections of the eye. Boston: Little, Brown, 1986: 563-585. 4. Blake PA, Weaver RE, Hollis DG. Diseases of humans (other than cholera) caused by vibrios. Ann Rev Med Microbiol, 198o; 34: 341-367. 5. Schewan JM, Veron M. Genus Vibrio. In: Buchanan RE, Gibbons NE, Eds. Bergey's manual of determinative bacteriology. Baltimore: Williams and Wilkins, 1974: 340-345.
Achromobacter Group B replacement valve endocarditis Accepted for publication 29 November 1989 Sir, We wish to report a case of late replacement valve endocarditis due to Achromobacter G r o u p B, an unusual organism that has not previously been implicated as a cause of prosthetic valve endocarditis (PVE). In early October 1987, a 28-year-old m a n was found to have Streptococcus sanguis endocarditis involving a bicuspid aortic valve. Despite appropriate antibiotic therapy, the patient deteriorated with marked aortic valve regurgitation. In m i d - O c t o b e r , the aortic valve was replaced by a p u l m o n a r y autograft and a fresh p u l m o n a r y homograft was inserted. T h e post-operative course was uneventful. T h e patient returned in M a r c h I988 with a week's history of lethargy, malaise, pleuritic chest pain, sweating and exertional dyspnoea. On examination, a low-grade fever was the sole abnormality detected. A short ejection systolic m u r m u r was unchanged from the time of his original surgery. Investigations revealed a neutrophil leucocytosis ( i 3 o o o x l o G / 1 ) , raised E S R ( 5 5 m m / I h ) and C-reactive protein (85 mg/1). Chest radiographs showed an enlarged cardiac silhouette and electrocardiography revealed non-specific T - w a v e changes. Although the replacement p u l m o n a r y homograft could not be seen, M - m o d e ethocardiography did not show any evidence of autograft regurgitation or vegatations. T h r e e consecutive sets of blood cultures yielded growth of a G r a m - n e g a t i v e bacillus in all six bottles after 24 h incubation. T h e isolate was identified as Achromobacter G r o u p B. N o clinical or laboratory evidence of infection outside the cardiovascular system could be found; infective endocarditis was diagnosed. T h e organism was sensitive to aminoglycosides, cephalosporins, amoxycillin/clavulanate, ciprofloxacin, erythromycin and tetracycline but resistant to penicillins, sulphonamides, t r i m e t h o p r i m and rifampicin. Intravenous therapy with cefuroxime (1"5 g t.d.s.) and gentamicin was given for 6 weeks. Dosage of the latter was controlled by serum assays so as to give peaks of 5-1o rag/1 and troughs less than 2 rag/1. Peak and trough serum bactericidal titres were 32 and 4 respectively. T h e patient improved and remained well at review I year later.
Letters to the Editor
263
T h e presenting features of this patient, in association with repeatedly early positive blood cultures and indirect evidence of cardiac involvement without an alternative source of infection, strongly supported a clinical diagnosis of infective endocarditis. 1 PVE is conventionally divided into early ( < 4 months post-operatively) and late. T h e latter, unlike early PVE, is more likely to have a chronic presentation and involve pathogens of low virulence. Gram-negative bacilli are responsible for less than ~5 % cases and the mortality rate is lower (45 %)- Isolated reports record infection in late PVE with a wide range of Gram-negative organisms. 2'3 T h e genus Achromobacter comprises non-fermenting, peritrichous, saccharolytic Gram-negative bacilli. T h e only named, and the best known, species is Achromobacter xylosoxidans, but six other taxa (Groups A - F ) have infrequently been isolated from patients whose disease was of the type usually related to infection with late PVE organisms. 4 Although unspecified Achromobacter species were reported in one review as having been implicated in PVE, ~ the two cases referred to were of early-onset endocarditis following surgery for congenital heart disease and did not involve replacement valves. 5 Defective ethylene oxide gaseous sterilisation of the extracorporeal heart p u m p was implicated on that occasion. Although it is assumed that late infections are not acquired at the time of original surgery, they may in fact be due to organisms which lie dormant after their introduction in the operating theatre) In the case of our patient, we feel that the organism concerned was probably introduced during surgery. Investigations into various possible routes of entry were unrewarding. N o source of infection could be proven in this episode which is the first recorded case of Achromobacter G r o u p B endocarditis. (We thank Mr B. Holmes, Central Public Health Laboratory, Colindale, London for his help in identifying the organisms and Dr S. J. Eykyn, St Thomas' Hospital, London for her advice with management of the patient.)
* Princess Mary's Royal Air Force Hospital, and the t Royal Air Force Institute of Pathology and Tropical Medicine, Halton, Aylesbury, Buckinghamshire HP22 5PG, U.K.
K. P. McKinley*
T. J. Laundy* R. G. Mastertont~.
~: Address correspondence to: Squadron Leader R. G. Masterton.
References i. Dismukes WE, Karchmer AW, Buckley MJ, Austen WG, Swartz MN. Prosthetic valve endocarditis. Analysis of 38 cases. Circulation 1973 ; 48 : 365-377. 2. Moore-Gillon J, Eykyn SJ, Phillips I. Prosthetic valve endocarditis. Br Med J I983; 287: 739-741. 3. Cohen PS, Maguire JH, Weinstein L. Infective endocarditis caused by Gram-negative bacteria: a review of the literature, I945-I977. Pros Cardiovasc Dis I98o; 22: 2o5-24I. 4. Holmes B, Pinning CA, Dawson CA. A probability matrix for the identification of Gramnegative, aerobic, non-fermentative bacteria that grow on nutrient agar. J Gen Microbiol I986; x32: I827-I842. 5. Linde LM, Heins I-IL. Bacterial endocarditis following surgery for congential heart disease. New EnglJ Med ~96o; 263: 65-69.
