Phenotypic and genotypic characterization of Neisseria gonorrhoeae in parts of Italy: detection of a multiresistant cluster circulating in a heterosexual network.

Data concerning Neisseria gonorrhoeae infections in Italy are scarce, and there is little information on the phenotypic and genotypic characteristics of the circulating strains. In this study, 326 isolates collected from 397 patients, with or without concurrent human immunodeficiency virus (HIV) infection, were cultured and characterized by serovar and antimicrobial susceptibility to five antimicrobials. N. gonorrhoeae multi-antigen sequence typing (NG-MAST) was also performed for strain characterization and to identify a transmission network. Gonococcal infection was diagnosed in 364 males and 33 females, 296 of whom were Italian and 96 of whom were foreigners (nationality was unknown in five cases). Among the 364 males, 197 were heterosexual, and the median age was 31 years. Approximately 8.3% of all the investigated patients were HIV-1-positive. The isolates were assigned to three different serovars (IA, IB, IA/IB), IB being the most frequently encountered. A significant rate of resistant gonococci was also observed; 34%, 25.5% and 19.1% of ciprofloxacin-resistant, penicillin-resistant and tetracycline-resistant phenotypes, respectively, were detected, and 10.2% of strains were multidrug-resistant. Together with the presence of different sequence types (STs), identified by NG-MAST, a multidrug-resistant cluster, ST661, was detected in a heterosexual network in a precise geographical area of the country. In particular, all strains belonging to ST661 showed identical profiles according to pulsed-field gel electrophoresis (PFGE), all were serotype IB, and all were resistant to penicillin, ciprofloxacin and tetracycline.

[Treponemal hemagglutination test (TPHA). Validity of the micromethod using dilutions of sera 1/20-1/40]. / Test di emoagglutinazione treponemica (TPHA). Validità del micrometodo esoguito con le diluizioni dei sieri 1/20-1/40.

The Authors studied the possibility to use, for the carrying out of the TPHA micromethod, higher serum dilutions, as preliminary investigations had pointed out an insufficient sensitivity of the reaction performed at the 1:80 - 1:160 dilutions, particularly in the primary-secondary phase of the luetic infection. The Authors controlled, preliminarily, that at the dilutions studied, no unacceptable increase of spontaneous hemagglutinations and false positive reactions took place in the test sera. The investigation stressed the acceptability of the methodological modification set forth.

TPHA test. Experience at the Clinic of Dermatology, University of Milan.

The results of serological investigations with the treponemal haemagglutination (TPHA) test are reported in a large number of luetic and non-luetic patients. From these the following conclusions can be drawn: (1) The sensitivity of the TPHA test is decreased if the test is carried out with micromethods; however, in our opinion, the same degree of sensitivity can be obtained either with the macromethod at dilution 1/80-1/60 or with micromethods at 1/20-1/40. (2) The sensitivity of this test is high, being similar to that of the fluorescent treponemal antibody absorption (FTA-ABS) test in primary and secondary syphilis and even higher than that of the FTA-ABS test in treated subjects. (3) The specificity of the reaction is high, as demonstrated by examining sera in patients with a negative history and clinical examination together with negative results to Treponema pallidum immobilisation (TPI) and FTA-ABS tests, and by studying biological false positive sera. (4) For the serological screening, it may be sufficient to perform the TPHA test with the 1/20-1/40 micromethod together with the Venereal Disease Research Laboratory (VDRL) test. In patients with suspected syphilis, it is advisable to perform the TPHA test by the macromethod, in combination with the FTA-ABS test.

Seroprevalence of herpes simplex virus type 2 infection among attendees of a sexually transmitted disease clinic in Italy. Italian Herpes Forum.

BACKGROUND AND OBJECTIVES: An increased prevalence of herpes simplex virus type 2 (HSV-2) infection has been recently observed in industrialized countries. GOAL: To determine HSV-2 seroprevalence in a high-risk population in Italy. STUDY DESIGN: A cross-sectional study was performed to ascertain the HSV-2 prevalence among 919 persons attending an STD clinic in northern Italy. A HSV-2-specific glycoprotein G-2-based immunoglobulin G enzyme-linked immunoabsorbent assay (Gull/Meridian ELISA; Meridian Diagnostics, Cincinnati, OH) was used and validated against Western blot analysis. RESULTS: A prevalence of 24.6% was found without differences between males and females. Seroprevalence increased with age and number of partners during the previous year. Compared with Western blot analysis, the Gull/Meridian ELISA showed a sensitivity of 91.9% and a specificity of 98%, and positive and negative predictive values of 93.9% and 97.4%, respectively. CONCLUSION: This is the first Italian survey of HSV-2 infection conducted with a properly validated, Food and Drug Administration-approved, type-specific serologic method in a high-risk population. It is likely that between one to three million adults are infected with HSV-2.