International Journal of STD & AIDS 1992: 3: 430-433
ORIGINAL ARTICLE
Gonorrhoea: signs, symptoms and serogroups P J Horner MA MRCPl, R J Coker MRCPl, A Turner-, M S Shafi MB BS FRCPath3 and S M Murphy MRCP 1 lPatrick Clements Clinic and 3Department of Microbiology, Central Middlesex Hospital, Acton Lane, London NWlO TNS and2Gonococcus Reference Unit, Public Health Laboratory, Myrtle Road, Kingsdown, Bristol BS2 BEL, UK Summary: Over 19 weeks, 104 male patients attending a genito.urina;y medi.c~ne clinic with gonococcal urethritis were asked to complete a queStiOnnal:e.detailing symptoms. Sixty-seven questionnaires were d~ly ~ompleted. The exammmg nurse documented signs. Ninety-one isolates of Neisseria gonorrhoeae were ser~grou~ed and auxotyped, 55 of these were from patients who had completed a questionnaire. Patients presented earlier if they had a past history of gonorrhoea (p=O.02). The serogroup of N. gon~rrhoeae di~ not infh.,!enc.e t~e. a~ount of discharg.e, the prese~ce of meatal inflammation, dysuria or penile tip irritation or the delar m presentatIo~ after appearance of discharge. Auxotype AHU was not associated WIthasymptomatic gonorrhoea. Keywords: Neisseria gonorrhoeae, serogroup, auxotype, urethritis, men
INTRODUCTION
PATIENTS
The major outer membrane protein of N. gonorrhoeae can be classified into two mutually exclusive subclasses, protein lA and protein lB, which correspond to serogroups WI and WII/III respectively'. These pro~eins~ although rela~ed2, dif~er structurally and antigenicallyv". Protem IA hes mostly within the cell membrane, with only a short terminal portion exposed whilst protein IB has a relatively large portion exposed on the surface with both terminal regions located within the membrane. Despite these structural differences both proteins perform the same functional role of porins, allowing the passage of ions and the selective uptake of nutrients through the impermeable outer membrane':", Studies have shown that the phenotypic traits of N. gonorrhoeae are important in disease expression. Protein IA has been associated with disseminated N. gonorrhoeae infection and asymptomatic gonorrhoea in men, as have nutritional requirements for arginine, hypoxanthine and uracil (auxotype AHU)7-lO. No association with protein I subclass and the development of local complications has been found in women". A prospective study was conducted to evaluate whether the serogroup or auxotype of N. gonorrhoeae influenced the signs and symptoms of gonococcal urethritis in men.
Over a total of 19 weeks, 104 men with gonococcal urethritis attended the Patrick Clements Clinic. Patients were asked to complete a questionnaire, giving symptom details, if Gram negative int:acellular diplococci were seen on urethral Gram stam. The following data were collected; presence of urethral discharge, dysuria and penile tip irritation. The amount of urethral discharge was described as small, moderate or large. The examining nurse documented the following signs on a standardized form; whether a discharge was visible prior to or following urethral massage and whether meatal inflammation or balanitis was present. Information detailing recent sexual partners and past history of gonorrhoea was taken retrospectively from the notes. This was not available in one patient who completed a questionnaire. For those patients who did not complete a questionnaire, details of signs and symptoms were taken retrospectively from the notes.
Correspondence to: Dr P J Horner. [efferiss Wing. St Mary's Hospital, Praed Street. London W2 1NY. UK
Isolation, identification and serogrouping Urethral swabs from the patients were cultured on heated blood (chocolate) and New York City selective agar. Colonies with morphology suggestive of Neisseria sp. were stained by Gram's method and tested for oxidase production; oxidase positive Gram negative diplococci were then identified using sugar reactions. Ninety-one isolates of N. gonorrhoeae were sent to the PHLS Gonococcus
Horner et al. Gonorrhoea: signs, symptoms and serogroups
Reference Unit, Bristol (GRU) for confirmation of identity and serogrouping. At the GRU the identity of the isolates was confirmed as N. gonorrhoeae using appropriate sugars incorporated into cysteine trypticase agar (CTA medium, Beckton Dickinson, Cockeysville MD, USA). The serogroup was determined using the Phadebact Monoclonal GC test (Novo Nordisk Diagnostics Ltd, Cambridge). This test detects protein I on the surface of N. gonorrhoeae by coagglutination with a suspension of non-viable Staphylococcus aureus to which is attached either a monoclonal antibody to protein IA or an antibody to protein lB. The test was performed according to the manufacturer's instructions. The defined medium of Copley and Egglestone'! was used to test for nutritional requirements for proline, arginine, hypoxanthine and uracil. In addition the ability of ornithine to replace a requirement for arginine was tested. A multi-point inoculator was used to deliver approximately 2.5 X 105 cfu of each strain onto plates. The nutritional requirements of a strain were read as no growth on the plate containing that amino acid or nucleic acid after 18 h at 37°C in 5% CO 2, Five reference organisms (NCTC Nos 10928, 10930-10933) were included in each batch of organisms 12.
Table 1. Factors influencing the time of presentation from appearance of discharge in patients with gonorrhoea Time to presentation (days) Less More than than Total 3 3 Past history of gonorrhoea
Yes No Total Contact Regular Casual Total Penile tip Present irritation Absent Total Dysuria Present Absent Total Perceived amount > Small Small discharge Total Observed visible Present Absent" discharge Total
RESULTS
Sixty-eight patients with gonococcal urethritis ~ompleted a questionnaire, including 55 from whom Isolates were subsequently serogrouped. One patient was asymptomatic. Patients with a discharge were more likely (P=0.02) to present earlier if they had a history of gonorrhoea (Table 1). Delay in presentation after appearance of discharge was mdependent of the amount of discharge, presence of dysuria, and whether the contact was regular or casual (Table 1). Nineteen (37%) of 51 patients with an overt discharge perceived a small discharge whereas 9 (52%) of 17 with a discharge which was only visible on urethral stripping perceived a significant discharge (McNemar's test with continuity correction P=0.09). Serogroup did not influence (Table 2) the amount of discharge, the presence of meatal inflammation, dysuria or penile tip irritation and the delay in presentation after ~ppearance of discharge. There was no difference m serogroup distribution (P=0.79) between those patients who did or did not complete a questionnaire. Thirteen of the 91 isolates were auxotype AHU. Information on symptoms and signs was available on 12 of these; one was asymptomatic.
12
6 18 10 8 18 13 5 18 14 4 18 11 7 18 14 4 18
15 33 48 23 25 48
22
27 49 34
15 49 30
19 49 36 13
49
27 39
x2 =5.41 P=0.02
66
33
~=O.08
33 66 35 32 67 48 19 67 41 26 67 50 17 67
P=0.78 X2=2.92
P=O.09 X2=O.14 P=0.71
X2=0.08 P=0.78 Fisher's exact test P=O.99
"No discharge visible before urethral massage
Table 2. Patients' symptoms and signs correlated with serogroup of N. gonorrhoeae Serogroup lA 18
Statistical analysis Chi-squared with Yates' correction, or when appropriate Fisher's exact test, were used to analyse the data.
431
Present Absent Total Present Dysuria Absent Total Perceived amount > Small :S;;Small of discharge Total Observed visible Present Absent" discharge Total Meatal Present inflammation Absent Total Penile tip irritation
9 8 17 9 8 17 13 4 17 13 4 17 8 9 17
17 21 38
28 10 38
21 17 38
28
10 38 18 20 38
Total
26 29 55 37 18 55
,,)=0.07
34
X2= 1.43
21 55 41 14 55 26 29 55
P=0.23
P=0.79 X2=1.45 P=0.23
Fisher's exact test P=1 i=0.07
P=0.79
"No discharge visible before urethral massage
Four of 91 patients had no symptoms at presentation. N. gonorrhoeae serogroup protein IA was isolated from two of these patients and serogroup protein IB from the other two. DISCUSSION
Our findings differ from those of Ruden et al. 13 who found that protein IA gonococcal isolates were associated with less objective discharge than protein LB isolates. Although our numbers are small the trend was for patients with N. gonorrhoeae protein IA infection to be more likely to perceive a substantial discharge than those infected with
432 ,/
International Journal of STD & AIDS Volume 3 November/December 1992
serogroup protein lB. The reason for the difference in our findings is unclear. Although the correlation between a patient's subjective perception of his discharge and clinical findings was poor, our study was not large enough to show a significant difference. The objective clinical findings will be dependent on the time elapsed since the patient last voided urine. It may be that this is an important variable which needs to be controlled for during statistical analysis of objective signs in patients with urethritis. Crawford et al. in a retrospective study found that N. gonorrhoeae auxotype AHU was associated with asymptomatic gonorrhoea in men9,10. We found no such association. Why our findings differ from those of Crawford et al. is unclear. It suggests that asymptomatic gonorrhoea is predisposed to by other phenotypic characteristics of N. gonorrhoeae. Auxotype AHU was probably associated with this/these in their study but not in ours. The clinical presentation of gonorrhoea is dependent on a number of factors including the virulence of the infecting strain and the host's immune response. Current evidence suggests that protein I may be important in both the virulence of N. gonorrhoeae and as a target for the immune response-'. Protein I has the ability to translocate from the gonococcus into lipid bilayers and human erythrocytes- 14. More recently it has been shown that when protein I is inserted into the membrane of neutrophils degranulation is inhibited15. It is unclear whether protein I can transfer from gonococci to neutrophils in vivo. If it does occur then it is possible that this mechanism might inhibit intracellular killing of gonococci by inhibiting release of granule proteins into maturing phagolysosomes". Specific but incomplete protection against infection with the homologous serovar of N. gonorrhoeae has been observed in women". Much more is known about the humoral response to N. gonorrhoea than the cell-mediated response'". Monoclonal antibodies against protein IA and IB have been demonstrated in vitro to be bactericidal in the presence of complement and to act as an opsonin19,20 . Protein I is one of the predominant antigens in both the genital IgG and IgA antibody response. Men have a qualitatively weaker response than women-l. Serum antibodies to protein I are also produced". No significant difference was found between the signs and symptoms of gonococcal urethritis caused by N. gonorrhoeae serogroups protein IA and protein lB. This suggests that although protein IA and IB are structurally distinct, they do not influence the local immune response and/or virulence of N. gonorrhoeae in causing urethritis in men. Our study confirms the findings by Schofield-', that a past history of urethritis was associated with earlier presentation at subsequent episodes. However, in contrast to his study, we found no association between duration of symptoms and
whether contacts were known to the patients. In our study patients used their own definition of 'casual' or 'regular' and this may explain the discrepancy. Although not statistically significant patients were more likely to present earlier if they had penile tip irritation. No association was found between this and meatal inflammation (P=O.71). Prostatic pain can be referred to the tip of the penis and it may be that these patients had prostatic involvement. In conclusion, we found no association between the signs, symptoms and serogroup of N. gonorrhoeae in men with gonococcal urethritis. Auxotype AHU was not associated with asymptomatic gonococcal urethritis.
Acknowledgements: We thank the nursing staff of the Patrick Clements Clinic for their assistance. We also thank Dr J Wadsworth for her advice on the statistical analysis. References 1 Sandstrom EG, Chen KCS, Buchanan TM. Serology of Neisseria gonorrhoeae: coagglutination serogroups WI and WIIIIII correspond to different outer membrane protein I molecules. Infect Immun 1982;38:462-70 2 Judd RC. Protein I: structure, function, and genetics. Clin Microbiol Rev 1989;2(suppl):S41-8 3 Barrera 0, Swanson J. Proteins IA and IB exhibit different surface exposures and orientations in the outer membranes of Neisseria gonorrhoeae. Infect Immun 1984;44:565-8 4 Knapp JS, Tam MR, Nowinski RC, Holmes KK, Sandstrom EG. Serological classification of Neisseria gonorrhoeae with use of monoclonal antibodies to the gonoccal outer membrane protein 1. J Infect Dis 1984;150:44-8 5 Douglas JT, Lee MD, Nikaido H. Protein I of Neisseria gonorrhoeae outer membrane is a porin. FEMS Microbiol Lett 1981;12:305-9 6 Young JD-E, BlakeM, Mauro A, Cohn ZA. Properties of the major outer membrane protein from Neisseria gonorrhoeae incorporated into model lipid membranes. Proc Natl Acad Sci USA 1983;80:3831-5 7 Brunham RC, Plummer F, Slaney L, Rand F, DeWitt W. Correlation of auxotype and protein I type with expression of disease due to Neisseria gonorrhoeae. J Infect Dis 1985; 152:339-43 8 Bohnhoff M, Morello JA, Lerner SA. Auxotypes, penicillin susceptibility, and serogroups of Neisseria gonorrhoeae from disseminated and uncomplicated infections. J Infect Dis 1986;154:225-30 9 Crawford G, Knapp JS, Hale J, Holmes KK. Asymptomatic gonorrhoea in men: caused by gonococci, with unique nutritional requirements. Science 1977;196:1352-3 10 Hook EW, Handsfield HH. Gonococcal infections in the adult. In: Holmes KK, Mardh P-A, Sparling PF, Wiesner PJ, eds. Sexually transmitted diseases. New York:McGraw-Hill, 1990:151-2 11 Copley CG, Egglestone SI. Auxotyping of Neisseria gonorrhoeae isolated in the United Kingdom. J Med Microbiol 1983;16:295-302 12 Catlin BW. Nutritional profiles of Neisseria gonorrhoeae, Neisseria meningitidis and Neisseria lactamica in chemically defined media and the use of growth requirements for gonococcal typing. J Infect Dis 1973;128:178-94
Horner et al. Gonorrhoea: signs, symptoms and serogroups 13 Ruden A-K, Backman M, Bygdeman S, Jonsson A, Ringertz 0, Sandstrom E. Gonorrhoea in heterosexual men. Correlation between gonococcal W serogroup, Chlamydia trachomatis infection and objective symptoms. Acta Derm Venerol 1986;66:453-6 14 Blake MS, Gotschlich EC. Gonococcal membrane proteins: speculation on their role in pathogenesis. Prog Allergy 1983;33:298-313 15 Haines KA, Yeh L, Blake MS, Cristello P, Korchak H, Weissman G. Protein I, a translocatable ion channel from Neisseria gonorrhoea, selectively inhibits exocytosis from human neutrophils without inhibiting 02- generation. J Bioi Chem 1988;263:945-51 16 Shafer WM. Interactions of gonococci with phagocytic cells. Ann Rev MicrobioI1989;43:121-45 17 Plummer FA, Simonsen IN, Chubb H, et al. Epidemiologic evidence for the development of serovar specific immunity after gonococcal infection. J Clin Invest 1989;83:1472-6 18 Cooper MS, Moticka EJ. Cellular immune responses during gonococcal and meningococcal infections. ClinMicrobiol Rev 1989;2(suppl):S29-34
433
19 Virji M, Zak K, Heckels JE. Monoclonal antibodies to gonococcal outer membrane protein IB: use in investigation of the potential protective effectof antibodies directed against conserved and type-specific epitopes. J Gen Microbiol 1986;132:1621-9 20 Virji M, Fletcher IN, Zak K, Heckels JE. The potential protective effect of monoclonal antibodies to gonococcalouter membrane protein lAo J Gen MicrobioI1987;133:2639-46 21 Lammel C], Sweet RL, Rice PA, et al. Antibody-antigen specificity in the immune response to infection with Neisseria gonorrhoeae. J Infect Dis 1985;152:990-1001 22 Zak K, Diaz J-L, Jackson D, Heckels JE. Antigenic variation during infection with Neisseria gonorrhoeae: detection of antibodies to surface proteins in sera of patients with gonorrhoea. J Infect Dis 1984;149:166-74 23 Schofield CBS. Some factors affecting the incubation period and duration of symptoms of urethritis in men. BrJ Vener Dis 1982;58:184-7
(Accepted 12 August 1992)
ORIGINAL ARTICLE
Gonorrhoea: signs, symptoms and serogroups P J Horner MA MRCPl, R J Coker MRCPl, A Turner-, M S Shafi MB BS FRCPath3 and S M Murphy MRCP 1 lPatrick Clements Clinic and 3Department of Microbiology, Central Middlesex Hospital, Acton Lane, London NWlO TNS and2Gonococcus Reference Unit, Public Health Laboratory, Myrtle Road, Kingsdown, Bristol BS2 BEL, UK Summary: Over 19 weeks, 104 male patients attending a genito.urina;y medi.c~ne clinic with gonococcal urethritis were asked to complete a queStiOnnal:e.detailing symptoms. Sixty-seven questionnaires were d~ly ~ompleted. The exammmg nurse documented signs. Ninety-one isolates of Neisseria gonorrhoeae were ser~grou~ed and auxotyped, 55 of these were from patients who had completed a questionnaire. Patients presented earlier if they had a past history of gonorrhoea (p=O.02). The serogroup of N. gon~rrhoeae di~ not infh.,!enc.e t~e. a~ount of discharg.e, the prese~ce of meatal inflammation, dysuria or penile tip irritation or the delar m presentatIo~ after appearance of discharge. Auxotype AHU was not associated WIthasymptomatic gonorrhoea. Keywords: Neisseria gonorrhoeae, serogroup, auxotype, urethritis, men
INTRODUCTION
PATIENTS
The major outer membrane protein of N. gonorrhoeae can be classified into two mutually exclusive subclasses, protein lA and protein lB, which correspond to serogroups WI and WII/III respectively'. These pro~eins~ although rela~ed2, dif~er structurally and antigenicallyv". Protem IA hes mostly within the cell membrane, with only a short terminal portion exposed whilst protein IB has a relatively large portion exposed on the surface with both terminal regions located within the membrane. Despite these structural differences both proteins perform the same functional role of porins, allowing the passage of ions and the selective uptake of nutrients through the impermeable outer membrane':", Studies have shown that the phenotypic traits of N. gonorrhoeae are important in disease expression. Protein IA has been associated with disseminated N. gonorrhoeae infection and asymptomatic gonorrhoea in men, as have nutritional requirements for arginine, hypoxanthine and uracil (auxotype AHU)7-lO. No association with protein I subclass and the development of local complications has been found in women". A prospective study was conducted to evaluate whether the serogroup or auxotype of N. gonorrhoeae influenced the signs and symptoms of gonococcal urethritis in men.
Over a total of 19 weeks, 104 men with gonococcal urethritis attended the Patrick Clements Clinic. Patients were asked to complete a questionnaire, giving symptom details, if Gram negative int:acellular diplococci were seen on urethral Gram stam. The following data were collected; presence of urethral discharge, dysuria and penile tip irritation. The amount of urethral discharge was described as small, moderate or large. The examining nurse documented the following signs on a standardized form; whether a discharge was visible prior to or following urethral massage and whether meatal inflammation or balanitis was present. Information detailing recent sexual partners and past history of gonorrhoea was taken retrospectively from the notes. This was not available in one patient who completed a questionnaire. For those patients who did not complete a questionnaire, details of signs and symptoms were taken retrospectively from the notes.
Correspondence to: Dr P J Horner. [efferiss Wing. St Mary's Hospital, Praed Street. London W2 1NY. UK
Isolation, identification and serogrouping Urethral swabs from the patients were cultured on heated blood (chocolate) and New York City selective agar. Colonies with morphology suggestive of Neisseria sp. were stained by Gram's method and tested for oxidase production; oxidase positive Gram negative diplococci were then identified using sugar reactions. Ninety-one isolates of N. gonorrhoeae were sent to the PHLS Gonococcus
Horner et al. Gonorrhoea: signs, symptoms and serogroups
Reference Unit, Bristol (GRU) for confirmation of identity and serogrouping. At the GRU the identity of the isolates was confirmed as N. gonorrhoeae using appropriate sugars incorporated into cysteine trypticase agar (CTA medium, Beckton Dickinson, Cockeysville MD, USA). The serogroup was determined using the Phadebact Monoclonal GC test (Novo Nordisk Diagnostics Ltd, Cambridge). This test detects protein I on the surface of N. gonorrhoeae by coagglutination with a suspension of non-viable Staphylococcus aureus to which is attached either a monoclonal antibody to protein IA or an antibody to protein lB. The test was performed according to the manufacturer's instructions. The defined medium of Copley and Egglestone'! was used to test for nutritional requirements for proline, arginine, hypoxanthine and uracil. In addition the ability of ornithine to replace a requirement for arginine was tested. A multi-point inoculator was used to deliver approximately 2.5 X 105 cfu of each strain onto plates. The nutritional requirements of a strain were read as no growth on the plate containing that amino acid or nucleic acid after 18 h at 37°C in 5% CO 2, Five reference organisms (NCTC Nos 10928, 10930-10933) were included in each batch of organisms 12.
Table 1. Factors influencing the time of presentation from appearance of discharge in patients with gonorrhoea Time to presentation (days) Less More than than Total 3 3 Past history of gonorrhoea
Yes No Total Contact Regular Casual Total Penile tip Present irritation Absent Total Dysuria Present Absent Total Perceived amount > Small Small discharge Total Observed visible Present Absent" discharge Total
RESULTS
Sixty-eight patients with gonococcal urethritis ~ompleted a questionnaire, including 55 from whom Isolates were subsequently serogrouped. One patient was asymptomatic. Patients with a discharge were more likely (P=0.02) to present earlier if they had a history of gonorrhoea (Table 1). Delay in presentation after appearance of discharge was mdependent of the amount of discharge, presence of dysuria, and whether the contact was regular or casual (Table 1). Nineteen (37%) of 51 patients with an overt discharge perceived a small discharge whereas 9 (52%) of 17 with a discharge which was only visible on urethral stripping perceived a significant discharge (McNemar's test with continuity correction P=0.09). Serogroup did not influence (Table 2) the amount of discharge, the presence of meatal inflammation, dysuria or penile tip irritation and the delay in presentation after ~ppearance of discharge. There was no difference m serogroup distribution (P=0.79) between those patients who did or did not complete a questionnaire. Thirteen of the 91 isolates were auxotype AHU. Information on symptoms and signs was available on 12 of these; one was asymptomatic.
12
6 18 10 8 18 13 5 18 14 4 18 11 7 18 14 4 18
15 33 48 23 25 48
22
27 49 34
15 49 30
19 49 36 13
49
27 39
x2 =5.41 P=0.02
66
33
~=O.08
33 66 35 32 67 48 19 67 41 26 67 50 17 67
P=0.78 X2=2.92
P=O.09 X2=O.14 P=0.71
X2=0.08 P=0.78 Fisher's exact test P=O.99
"No discharge visible before urethral massage
Table 2. Patients' symptoms and signs correlated with serogroup of N. gonorrhoeae Serogroup lA 18
Statistical analysis Chi-squared with Yates' correction, or when appropriate Fisher's exact test, were used to analyse the data.
431
Present Absent Total Present Dysuria Absent Total Perceived amount > Small :S;;Small of discharge Total Observed visible Present Absent" discharge Total Meatal Present inflammation Absent Total Penile tip irritation
9 8 17 9 8 17 13 4 17 13 4 17 8 9 17
17 21 38
28 10 38
21 17 38
28
10 38 18 20 38
Total
26 29 55 37 18 55
,,)=0.07
34
X2= 1.43
21 55 41 14 55 26 29 55
P=0.23
P=0.79 X2=1.45 P=0.23
Fisher's exact test P=1 i=0.07
P=0.79
"No discharge visible before urethral massage
Four of 91 patients had no symptoms at presentation. N. gonorrhoeae serogroup protein IA was isolated from two of these patients and serogroup protein IB from the other two. DISCUSSION
Our findings differ from those of Ruden et al. 13 who found that protein IA gonococcal isolates were associated with less objective discharge than protein LB isolates. Although our numbers are small the trend was for patients with N. gonorrhoeae protein IA infection to be more likely to perceive a substantial discharge than those infected with
432 ,/
International Journal of STD & AIDS Volume 3 November/December 1992
serogroup protein lB. The reason for the difference in our findings is unclear. Although the correlation between a patient's subjective perception of his discharge and clinical findings was poor, our study was not large enough to show a significant difference. The objective clinical findings will be dependent on the time elapsed since the patient last voided urine. It may be that this is an important variable which needs to be controlled for during statistical analysis of objective signs in patients with urethritis. Crawford et al. in a retrospective study found that N. gonorrhoeae auxotype AHU was associated with asymptomatic gonorrhoea in men9,10. We found no such association. Why our findings differ from those of Crawford et al. is unclear. It suggests that asymptomatic gonorrhoea is predisposed to by other phenotypic characteristics of N. gonorrhoeae. Auxotype AHU was probably associated with this/these in their study but not in ours. The clinical presentation of gonorrhoea is dependent on a number of factors including the virulence of the infecting strain and the host's immune response. Current evidence suggests that protein I may be important in both the virulence of N. gonorrhoeae and as a target for the immune response-'. Protein I has the ability to translocate from the gonococcus into lipid bilayers and human erythrocytes- 14. More recently it has been shown that when protein I is inserted into the membrane of neutrophils degranulation is inhibited15. It is unclear whether protein I can transfer from gonococci to neutrophils in vivo. If it does occur then it is possible that this mechanism might inhibit intracellular killing of gonococci by inhibiting release of granule proteins into maturing phagolysosomes". Specific but incomplete protection against infection with the homologous serovar of N. gonorrhoeae has been observed in women". Much more is known about the humoral response to N. gonorrhoea than the cell-mediated response'". Monoclonal antibodies against protein IA and IB have been demonstrated in vitro to be bactericidal in the presence of complement and to act as an opsonin19,20 . Protein I is one of the predominant antigens in both the genital IgG and IgA antibody response. Men have a qualitatively weaker response than women-l. Serum antibodies to protein I are also produced". No significant difference was found between the signs and symptoms of gonococcal urethritis caused by N. gonorrhoeae serogroups protein IA and protein lB. This suggests that although protein IA and IB are structurally distinct, they do not influence the local immune response and/or virulence of N. gonorrhoeae in causing urethritis in men. Our study confirms the findings by Schofield-', that a past history of urethritis was associated with earlier presentation at subsequent episodes. However, in contrast to his study, we found no association between duration of symptoms and
whether contacts were known to the patients. In our study patients used their own definition of 'casual' or 'regular' and this may explain the discrepancy. Although not statistically significant patients were more likely to present earlier if they had penile tip irritation. No association was found between this and meatal inflammation (P=O.71). Prostatic pain can be referred to the tip of the penis and it may be that these patients had prostatic involvement. In conclusion, we found no association between the signs, symptoms and serogroup of N. gonorrhoeae in men with gonococcal urethritis. Auxotype AHU was not associated with asymptomatic gonococcal urethritis.
Acknowledgements: We thank the nursing staff of the Patrick Clements Clinic for their assistance. We also thank Dr J Wadsworth for her advice on the statistical analysis. References 1 Sandstrom EG, Chen KCS, Buchanan TM. Serology of Neisseria gonorrhoeae: coagglutination serogroups WI and WIIIIII correspond to different outer membrane protein I molecules. Infect Immun 1982;38:462-70 2 Judd RC. Protein I: structure, function, and genetics. Clin Microbiol Rev 1989;2(suppl):S41-8 3 Barrera 0, Swanson J. Proteins IA and IB exhibit different surface exposures and orientations in the outer membranes of Neisseria gonorrhoeae. Infect Immun 1984;44:565-8 4 Knapp JS, Tam MR, Nowinski RC, Holmes KK, Sandstrom EG. Serological classification of Neisseria gonorrhoeae with use of monoclonal antibodies to the gonoccal outer membrane protein 1. J Infect Dis 1984;150:44-8 5 Douglas JT, Lee MD, Nikaido H. Protein I of Neisseria gonorrhoeae outer membrane is a porin. FEMS Microbiol Lett 1981;12:305-9 6 Young JD-E, BlakeM, Mauro A, Cohn ZA. Properties of the major outer membrane protein from Neisseria gonorrhoeae incorporated into model lipid membranes. Proc Natl Acad Sci USA 1983;80:3831-5 7 Brunham RC, Plummer F, Slaney L, Rand F, DeWitt W. Correlation of auxotype and protein I type with expression of disease due to Neisseria gonorrhoeae. J Infect Dis 1985; 152:339-43 8 Bohnhoff M, Morello JA, Lerner SA. Auxotypes, penicillin susceptibility, and serogroups of Neisseria gonorrhoeae from disseminated and uncomplicated infections. J Infect Dis 1986;154:225-30 9 Crawford G, Knapp JS, Hale J, Holmes KK. Asymptomatic gonorrhoea in men: caused by gonococci, with unique nutritional requirements. Science 1977;196:1352-3 10 Hook EW, Handsfield HH. Gonococcal infections in the adult. In: Holmes KK, Mardh P-A, Sparling PF, Wiesner PJ, eds. Sexually transmitted diseases. New York:McGraw-Hill, 1990:151-2 11 Copley CG, Egglestone SI. Auxotyping of Neisseria gonorrhoeae isolated in the United Kingdom. J Med Microbiol 1983;16:295-302 12 Catlin BW. Nutritional profiles of Neisseria gonorrhoeae, Neisseria meningitidis and Neisseria lactamica in chemically defined media and the use of growth requirements for gonococcal typing. J Infect Dis 1973;128:178-94
Horner et al. Gonorrhoea: signs, symptoms and serogroups 13 Ruden A-K, Backman M, Bygdeman S, Jonsson A, Ringertz 0, Sandstrom E. Gonorrhoea in heterosexual men. Correlation between gonococcal W serogroup, Chlamydia trachomatis infection and objective symptoms. Acta Derm Venerol 1986;66:453-6 14 Blake MS, Gotschlich EC. Gonococcal membrane proteins: speculation on their role in pathogenesis. Prog Allergy 1983;33:298-313 15 Haines KA, Yeh L, Blake MS, Cristello P, Korchak H, Weissman G. Protein I, a translocatable ion channel from Neisseria gonorrhoea, selectively inhibits exocytosis from human neutrophils without inhibiting 02- generation. J Bioi Chem 1988;263:945-51 16 Shafer WM. Interactions of gonococci with phagocytic cells. Ann Rev MicrobioI1989;43:121-45 17 Plummer FA, Simonsen IN, Chubb H, et al. Epidemiologic evidence for the development of serovar specific immunity after gonococcal infection. J Clin Invest 1989;83:1472-6 18 Cooper MS, Moticka EJ. Cellular immune responses during gonococcal and meningococcal infections. ClinMicrobiol Rev 1989;2(suppl):S29-34
433
19 Virji M, Zak K, Heckels JE. Monoclonal antibodies to gonococcal outer membrane protein IB: use in investigation of the potential protective effectof antibodies directed against conserved and type-specific epitopes. J Gen Microbiol 1986;132:1621-9 20 Virji M, Fletcher IN, Zak K, Heckels JE. The potential protective effect of monoclonal antibodies to gonococcalouter membrane protein lAo J Gen MicrobioI1987;133:2639-46 21 Lammel C], Sweet RL, Rice PA, et al. Antibody-antigen specificity in the immune response to infection with Neisseria gonorrhoeae. J Infect Dis 1985;152:990-1001 22 Zak K, Diaz J-L, Jackson D, Heckels JE. Antigenic variation during infection with Neisseria gonorrhoeae: detection of antibodies to surface proteins in sera of patients with gonorrhoea. J Infect Dis 1984;149:166-74 23 Schofield CBS. Some factors affecting the incubation period and duration of symptoms of urethritis in men. BrJ Vener Dis 1982;58:184-7
(Accepted 12 August 1992)
