Detection of Chlamydia trachomatis in urine from men with urethritis.

The performance of a commercial EIA (Chlamydiazyme) for detection of Chlamydia trachomatis in urine specimens was compared with that of culture of urethral samples from men with urethritis. The incidence of chlamydial infection on the basis of culture results was 34% (56/167). The sensitivity, specificity, positive and negative predictive values for the EIA were 55% (31/56), 98% (109/111), 94% (31/33) and 81% (109/134), respectively, compared with culture. Although this EIA has a high specificity, the low sensitivity makes it valueless as a clinical tool for demonstrating chlamydial antigen in urine from men with urethritis.

Markers of Neisseria gonorrhoeae for epidemiological studies.

Numerous attempts have been made to subclassify Neisseria gonorrhoeae. The properties of these various systems are reviewed. Classification based on the nutritional requirements, i.e. auxotyping, or on the reactivity against epitopes on protein I, the major outer membrane protein, i.e. serovar determination, are the most widely used systems. With the aid of these two classification systems, gonococcal infection can be viewed as a number of microepidemics each with its own dynamics. The tools now exist for a better understanding of gonococcal epidemiology. In many settings it is now feasible to amplify the decreasing prevalence of gonococcal infection by programs aimed at eradication of endemic gonorrhoea.

Genotypes and phenotypes of beta lactamase producing strains of Neisseria gonorrhoeae from African countries.

The phenotypes and genotypes of 26 beta lactamase (penicillinase) producing strains of Neisseria gonorrhoeae (PPNG) from African countries were investigated. Using the restriction enzyme technique nine different restriction enzyme patterns were found, two of them in 15 strains. Of the 26 strains, 16 belonged to serogroup WI (containing protein type IA) and 10 to serogroup WII/III (containing protein IB). Among the IA strains four different serovars were represented, whereas six serovars were found among the IB strains. Five different auxotypes were identified, of which proline requiring (found in 12 strains) and prototrophic (found in 10 strains) dominated. Twelve strains harboured a 4.4 megadalton as well as a 24.5 megadalton plasmid. A 3.2 megadalton plasmid was found in 14 strains, one of which also harboured a 24.5 megadalton plasmid. The 2.8 megadalton cryptic plasmid was present in all 26 strains. The MICs of doxycycline ranged from 0.25 to 2.0 mg/l; the MIC 50% for WI strains was 0.25 mg/l and for WII/WIII strains 1.0 mg/l. A total of 10 different combinations of restriction enzyme pattern, serovar, auxotype, and plasmid were seen in the 16 WI strains compared with eight such combinations in the 10 WII/WIII strains. As expected, the restriction enzyme technique and serological classification gave better differentiation than plasmid profiles and susceptibility to doxycycline. More relevantly, however, these techniques also compared favourably with auxotyping. When the different systems were combined, the sensitivity was greatly increased.

Serovars, auxotypes, and plasmid profiles of PPNG strains with Asian type plasmid isolated in Amsterdam.

In 1982 an increase of penicillinase producing strains of Neisseria gonorrhoeae (PPNG), carrying the 4.5 megadalton Asian type plasmid and the 24 megadalton transfer plasmid (Asia+), was observed in Amsterdam. The main auxotypes were proline requiring (Pro-) and proline and hypoxanthine requiring (Pro-Hyx-). Using two monoclonal antibody systems, it was shown that the serovars of strains with these auxotypes isolated in 1981 were different from those isolated in 1982, which indicated the start and end of microepidemics. Different serovars were also observed in Pro- and non-requiring (NR) Asia- PPNG strains isolated in 1981-2 and 1985 respectively. Only one serovar (Aedih/Arst) was common in strains isolated in 1981-2 as well as in 1985.

Antiviral therapy in AIDS. Clinical pharmacological properties and therapeutic experience to date.

The rapid spread of human immunodeficiency virus (HIV) infections and the grim outcome of these infections have focused interest on the possibilities for medical intervention. The end-stage of these infections, acquired immune deficiency syndrome (AIDS), was first recognised in 1981, and the causative agent isolated in 1983. Already several antiviral drugs have been investigated. One initially promising drug, suramin, was found to have a net harmful effect but another, zidovudine (azidothymidine) has been shown to prolong life in AIDS patients. The properties of these and several other antiviral drugs such as antimoniotungstate (HPA-23), foscarnet (phosphonoformate) ribavirin, dideoxynucleotides, and interferons, are reviewed. The role of immunomodulating modalities such as plasmapheresis, bone marrow transplantation, thymosin, interleukin-2, inosine pranobex (isoprinosine), and cyclosporin are also discussed. None of the currently available drugs hold promise as monotherapy. Through analysis of the experience with these drugs and the increasing knowledge of HIV pathogenesis, new drugs can be designed. It seems increasingly clear that drugs will eventually have to be used in combination in order to reduce toxicity, exploit therapeutic synergy, and reduce the risk of HIV resistance. The theoretical and experimental background for such combinations are currently being elucidated.

Comparison between serological classification and auxotyping in the analysis of Neisseria gonorrhoeae infections.

Auxotyping and serological classification, using monoclonal antibodies, were performed on 730 gonococcal strains. These strains were isolated from 725 consecutive patients seen at the Venereal Outpatients Clinic at the Department of Dermatology, Södersjukhuset, Stockholm, during one year, up to April 1983. Strains from patients with repeated gonococcal infections were, besides auxotyping and serological classification, analysed with restriction endonuclease cleavage. The strains were distributed into 16 auxotypes, of which the eight most common accounted for 97.4% of all isolates. The same strains were distributed into 38 serovars, of which the eight most common accounted for 88.4% of all isolates. When the two methods were combined, 98 combinations of auxotypes and serovars were seen. The eight most common combinations included 60.0% of all strains. Correlations were found between auxotypes and serogroups as well as serovars. The serological classification gave a better resolution compared with auxotyping; however, when the two systems were combined the sensitivity was highly increased.

Serovars, auxotypes, and plasmid contents of PPNG strains from outbreak in Amsterdam.

The first outbreak of penicillinase producing strains of Neisseria gonorrhoeae (PPNG) in Amsterdam in 1981-2 was caused mainly by African strains carrying the 24 megadalton transfer plasmid (Afr+) that were non-requiring (NR) and inhibited by phenylalanine (pheni), but African strains without the transfer plasmid (Afr-) that were NRpheni and Afr+ NR strains were also found. Serological classification, using two monoclonal antibody systems, showed that three main serovars (Ae/Av, Aedih/Arst, and Bacejk/Brpyust) could be distinguished in these PPNG strains, which indicated exchanges of plasmids in these serovars. The serovar Ae/Av predominated in the Afr+ and Bacejk/Brpyust in the Afr- strains.

Serological ecology of Neisseria gonorrhoeae (PPNG and non-PPNG) strains: Canadian perspective.

One hundred and thirty eight penicillinase producing Neisseria gonorrhoeae (PPNG) and 239 non-PPNG strains were characterised serologically using a panel of seven monoclonal antibodies directed against protein 1A and seven against protein 1B. An association between serovar and susceptibility to antimicrobial agents, auxotype, and plasmid content was observed. Serogroup WI strains were more sensitive to penicillin, ampicillin, tetracycline, erythromycin, cefoxitin, and cefuroxime. Sixty five (82%) of the 79 WI strains were typed as being serovar Aedgkih, and 47 (72%) of these strains required arginine, uracil, and hypoxanthine for growth (AUH-). Seventy one (44%) of 160 WII/WIII strains were serovar Bacejk, and 42 (59%) of these required proline, citrulline, and uracil for growth (PCU-) and were plasmid free. Serovars Bcgk, Beghjk, Bacjk, and Bajk were associated with resistance to antimicrobial agents. Analysis of PPNG isolates showed a new serovar, Af, which was associated with strains imported from Malaysia and Singapore that required proline and ornithine for growth (Pro-Orn-) and carried the 24.5 megadalton transfer plasmid, the 2.6 megadalton cryptic plasmid, and the 4.5 megadalton penicillinase producing plasmid. Other associations between serovar and geographical location were noted.

Suppression of concanavalin A-induced blastogenesis by HTLV-III-infected H9 cells.

The ability of cells infected with human T lymphotropic virus type III (HTLV-III) to suppress lymphocyte responses to concanavalin A (ConA) was evaluated. Thirty homosexual men, both HTLV-III seropositive and seronegative, and 11 seronegative laboratory personnel were studied. Peripheral blood lymphocytes from all groups had lower responses to ConA in the presence of HTLV-III-infected H9 cells than in the presence of uninfected H9 cells. Among HTLV-III-seropositive males, responses to ConA in the presence of infected or uninfected H9 cells correlated with the number of T4 cells present. The studies suggest that HTLV-III-infected cells can suppress normal lymphocyte responses. Possible mechanisms of this suppression are discussed.

Synergistic inhibition of human T-cell lymphotropic virus type III replication in vitro by phosphonoformate and recombinant alpha-A interferon.

Phosphonoformate and recombinant alpha-A interferon synergistically inhibited the replication of human T-cell lymphotropic virus type III in cultured peripheral blood lymphocytes. T-cell proliferative capability was maintained by this combination, and toxicity was minimal.

Detection of human T-cell lymphotropic virus type III-related antigens and anti-human T-cell lymphotropic virus type III antibodies by anticomplementary immunofluorescence.

Techniques presently available for detection of human T-cell lymphotropic virus type III (HTLV-III) antigens and antibodies are laborious or relatively nonsensitive. We adapted anticomplementary immunofluorescence (ACIF) for these purposes. In HTLV-III-infected cells, specific ACIF was demonstrated by a diffuse speckling pattern that often resulted in a peripheral cellular rim of fluorescence. A 97% concordance was demonstrated between the ACIF assay and other sensitive tests for HTLV-III antibody detection (Western blot and membrane immunofluorescence and fixed-cell immunofluorescence tests). The ACIF assay was both more sensitive and more specific when compared with the enzyme-linked immunosorbent assay. For detection of HTLV-III antigens, the ACIF assay appeared to be as sensitive as the reverse transcriptase assay and more sensitive, with less background reactivity, than the conventional immunofluorescence assay. The ACIF assay often detected low levels of HTLV-III antigens within 3 days of infection in vitro, compared with 5 to 7 days with the indirect immunofluorescence assay, and generally paralleled the reverse transcriptase assay. The ACIF assay is a simple, sensitive, and specific assay for detection of HTLV-III-related antigens and antibodies. It should prove useful in the diagnosis of HTLV-III infection, as well as in studies of pathogenesis.

Serologic classification and contact-tracing in the control of microepidemics of beta-lactamase-producing Neisseria gonorrhoeae.

Serologic classification of isolated gonococcal strains and thorough contact-tracing were proved to be valuable in controlling an indigenous outbreak of infections caused by beta-lactamase-producing Neisseria gonorrhoeae (PPNG). Only 1-2% of gonococcal strains isolated in Sweden are PPNG, and before 1983 most of them were imported. During January-August 1983, 43 PPNG strains were isolated from 42 patients in Gothenburg. The PPNG strains were auxotyped and classified serologically. PPNG strains of serogroup WI, serovar (subgroup) Ae and of the prototrophic auxotype were isolated from 27 patients, including six prostitutes. Information obtained at interviews with these patients indicated that there had been a chain of infections. Quick and thorough contact-tracing stopped this microepidemic within three months. The serologic classification of the PPNG strains helped us to concentrate the epidemiologic efforts on those persons known to be infected with the epidemic strain, to trace this infection to other parts of Sweden, and to determine when the outbreak was finished.

Detection of human anti-HTLV-III antibodies by indirect immunofluorescence using fixed cells.

Seropositivity to human T-cell lymphotrophic virus-III (HTLV-III) can have profound implications for the individual in whom it is detected. Simple and reliable tests are needed to confirm positivity by screening assays. In this study, detection of human antibodies by indirect immunofluorescence (IFA) on acetone-fixed HTLV-III infected H9 cells was evaluated in blood donors, patients with infectious or auto-immune diseases, and men with or at high risk for developing acquired immune deficiency syndrome (AIDS). Specific and nonspecific patterns of immunofluorescent reactivity were distinguished easily. None of 98 serums from blood donors was positive, while two of 33 serums from patients attending an infectious disease clinic, both homosexual men, were positive. Ninety-six percent of 24 serums from men with AIDS, 87 percent of 70 serums from men with lymphadenopathy, and 50 percent of 135 serums from healthy gay men were positive. These results paralleled those obtained by Western blotting and membrane immunofluorescence. In contrast, 11 and 4 percent, respectively, of these serums were judged as borderline or not interpretable by an enzyme-linked immunosorbent assay (ELISA). Of these serums, those that were positive by IFA were positive by Western blots, and 16 of the 17 IFA-negative serums were negative by Western blots. These studies indicate that IFA is a sensitive and specific assay for HTLV-III antibodies in human serums.

Inhibition of human T-cell lymphotropic virus type III in vitro by phosphonoformate.

Phosphonoformate, an inhibitor of reverse transcriptase in a number of retroviruses, was shown to have a dose-related inhibitory effect on human T-cell lymphotropic virus type III (HTLV-III) replication in the H9 cell line in vitro. HTLV-III replication was eliminated at a concentration of 680 mumol, a non-cytotoxic dose. A lower dose of 132 mumol inhibited HTLV-III replication by more than 98%, as measured by reverse transcriptase activity, compared with untreated infected cultures. Reverse transcriptase activity in HTLV-III particles was completely inhibited by 5.0 mumol phosphonoformate.

PIP: Phosphonoformate, an inhibitor of reverse transcriptase in a number of retroviruses, was shown to have a dose-related inhibitory effect on human T-cell lymphotropic virus type III (HTLV-III) replication in the H9 cell line in vitro. HTLV-III replication was eliminated at a concentration of 680 mcgmol, a noncytotoxic dose. A lower dose of 132 mcgmol inhibited HTLV-III replication by more than 98%, as measured by reverse transcriptase activity, compared with untreated infected cultures. Reverse transcriptase activity in HTLV-III particles was completely inhibited by 5 mcgmol of phosphonoformate. Growth of uninfected H9 cells was not affected by the concentration of the drug. In clinical trials to treat cytomegalovirus infection in immunocompromised patients, constant serum levels of between 100-450 mcgmol of phosphonoformate have been achieved in 140 subjects. Further studies are recommended to evaluate the potential of phosphonoformate in patients infected with HTLV-III. It may be the least toxic of the antiviral agents that have been shown to have anti-HTLV-III activity.

Gonococcal serovar distribution in Stockholm, with special reference to multiple infections and infected partners.

Serological classification with co-agglutination, using monoclonal antibody reagents, was used to classify gonococcal strains from 731 consecutive patients seen at the Venereal Outpatients clinic at the Department of Dermatology, Södersjukhuset, Stockholm, up to April 1983. The strains could be divided into two serogroups, WI and WII/III. For the identification of strains belonging to serogroup WI, six Protein IA specific antibody reagents were used, and for strains of serogroup WII/III, seven Protein IB specific antibody reagents. The serogroup WI could be further subdivided into eight different serovariants (serovars), and serogroup WII/III into 30 different serovars. All strains reacted with at least one monoclonal antibody reagent and no strain reacted with both WI and WII/III specific reagents. In both serogroups there was one serovar that was common among women and heterosexual men and another which was more frequent among homosexual men. The 84 contact pairs had strains of corresponding serovar in 95%. Among 258 patients with two or more gonococcal isolates on the same occasion, the isolates from 93% had the corresponding serovar. Repeated gonococcal infections were more frequent among heterosexual men than among women and more frequent among homosexual than among heterosexual men. The serological classification of N. gonorrhoeae is a stable and rapid method and a useful epidemiological tool.

Use of gonococcal W serogrouping in the evaluation of a clinical trial of rosoxacin.

Serogrouping by co-agglutination was used for the characterization of isolates of Neisseria gonorrhoeae in a clinical trial of rosoxacin in Stockholm. Twenty-four isolates (56%) belonged to serogroup WI, 17 (40%) to WII, and two (5%) to WIII. The proportion of WI isolates in Stockholm was reported in earlier studies to be approximately 40%. On the basis of serogrouping data and clinical information, five (10%) of 48 patients in this study were classified as therapeutic failures. Of the initial WI isolates, 22 (92%) of 24 were inhibited by less than or equal to 0.03 microgram of rosoxacin/ml, as compared with ten (59%) of 17 of the initial WII isolates (.05 greater than P greater than .01). Thus, this study might underestimate the failure rate as compared with that for patient populations in which WII isolates are more prevalent, since WI isolates are more susceptible to rosoxacin than WII isolates. A certain WII serovar was correlated with decreased susceptibility to rosoxacin (P less than .001). Correlations were found between decreased susceptibility to rosoxacin and decreased susceptibility to other antibiotics (P less than or equal to .01). A high frequency of side effects (40%) was seen among the patients studied.

Susceptibility of Neisseria gonorrhoeae to rifampicin and thiamphenicol: correlation with protein I antigenic determinants.

Tests of susceptibility to thiamphenicol and rifampicin were done for 85 strains of Neisseria gonorrhoeae, including 28 beta-lactamase-producing and three spectinomycin-resistant isolates. Strains were serogrouped by co-agglutination with 14 monoclonal antibodies that are specific for different antigenic determinants on protein I of the gonococcal outer membrane. Thus the isolates could be classified into one of the serogroups WI, WII, or WIII and could be subgrouped further into several serovars. The minimal inhibitory concentration (MIC) of thiamphenicol ranged between 0.125 and 4.0 micrograms/ml and that of rifampicin between 0.016 and 4.0 micrograms/ml. All isolates with a MIC of rifampicin of greater than or equal to 0.5 microgram/ml had a MIC of thiamphenicol of greater than or equal to 2.0 micrograms/ml. Decreased susceptibility (thiamphenicol MIC, greater than or equal to 1.0 microgram/ml; rifampicin MIC, greater than or equal to 0.5 microgram/ml) to both drugs was correlated with serogroup WII specificity and also correlated with strains that belonged to serovars characterized by a positive reaction with the WII monoclonal antibody 2G2.

Serological classification of Neisseria gonorrhoeae with use of monoclonal antibodies to gonococcal outer membrane protein I.

Identification of strain-specific markers on Neisseria gonorrhoeae that are capable of differentiating gonococci into a large number of distinct classes could facilitate analysis of patterns of gonorrhea transmission and application of gonorrhea control measures. A panel of 12 monoclonal antibodies to gonococcal outer membrane protein IA (PrIA) and IB (PrIB) was used to classify 1,433 strains serologically in a worldwide survey. Eighteen PrIA and 28 PrIB serovars were identified, and a nomenclature is proposed. Gonococcal strains were classified further by auxotyping. Auxotyping and serotyping served to classify the 1,433 isolates into 107 unique auxotype/serovar classes. Dual classification by auxotype and serovar can be used to identify epidemiologically related gonococcal infections in order to test the effectiveness of innovative, focused measures to control gonorrhea.

Serogrouping of Neisseria gonorrhoeae: correlation of serogroup with disseminated gonococcal infection.

Gonococci can be divided into serogroups WI, WII, and WIII by coagglutination. To assess the clinical correlation of serogroups of gonococci, we studied isolates of gonococci from patients with disseminated and uncomplicated gonococcal infections in three cities in the United States. Strains of Neisseria gonorrhoeae belonging to serogroup WI represented 85 (84%) of 101 isolates from patients with disseminated gonococcal infection (DGI) and 68 (40%) of 168 isolates from patients with uncomplicated gonorrhea (P less than .001). The auxotype Arg-, Hyx-, Ura- (AHU) represented 62 (61%) of 101 isolates from DGI and 54 (32%) of 168 isolates from uncomplicated infection (p less than .001); all AHU isolates were serogroup WI. Among other auxotypes, WI strains represented 25 (64%) of 39 isolates from patients with DGI and 14 (12%) of 114 from uncomplicated infections (P less than .001). In Atlanta only, 13 (34%) of 38 isolates from DGI were AHU, but 31 (82%) were serogroup WI (P less than .001). Thus gonococci of serogroup WI are associated with DGI in these cities of the United States, and this correlation appears to be independent of auxotype. Serogroup WI is correlated with serum resistance.

Serology of Neisseria gonorrhoeae: coagglutination serogroups WI and WII/III correspond to different outer membrane protein I molecules.

The 125I-labeled tryptic peptides of the outer membrane protein I of 33 previously characterized serological reference strains of Neisseria gonorrhoeae were investigated by peptide maps in relation to their coagglutination W serogroup. Serogroup WI strains tended to have lower-molecular-weight protein I molecules than did WII strains, and WIII strains had the highest-molecular-weight protein I molecules, although the serogroup could not be predicted from the molecular weights of the protein I molecules for a given strain. All 13 strains belonging to serogroup WI were found to have 11 peptides in common, as judged by their migration with respect to one another and to the internal marker valine in the peptide maps. Common peptides isolated from a given strain were found to comigrate with the corresponding common peptides from other strains in the same serogroup under various electrophoretic conditions. The 20 strains belonging to serogroups WII and WIII were all found to have 10 common peptides by the same criteria. When common peptides from serogroup WI were compared with the common peptides of serogroups WII and WIII, only three of these peptides appeared to be similar. Thus, two different outer membrane protein I molecules seem to exist which are mutually exclusive. Protein IA molecules contain the antigens recognized as serogroup WI, and protein IB molecules contain the antigens that characterize serogroups WII and WIII.