Validation of safety procedures for the cryopreservation of semen contaminated with hepatitis C virus in assisted reproductive technology.

BACKGROUND: In France, assisted reproductive technologies involving a hepatitis C virus (HCV)-infected man requires the cryopreservation of potentially infected semen (in order to establish the presence of HCV), hence the need for a safe and secure storage system. We evaluated the safety of high-security straws for the conservation of semen containing HCV RNA under routine conditions. METHODS: Ionomeric resin (IR) straws were filled with seminal plasma spiked with different concentrations of HCV RNA and sealed using a thermo-solder. After a 4% sodium hypochlorite treatment and/or cryopreservation for 7 days in liquid nitrogen, the outside ends of each straw were rinsed with RNAse-free water. RESULTS: No HCV RNA could be detected in any of the water samples. Additional samples included the rinsing water from straws sealed by thermo-solder and from the heating wire used to cut the end of straws containing HCV-positive semen. The latter samples were found positive for both HCV RNA and the protamine-2 gene expressed by spermatozoa. CONCLUSIONS: These results demonstrate the safety of IR straws, the filling system and the thermo-solder for cryopreservation of semen containing HCV in liquid nitrogen. Decontamination of the straw after sealing and the use of disposable scissors to open the straws are strongly recommended.

[Serum HRP-2 antigens and imported Plasmodium falciparum malaria: comparison of ParaSight-F and ICT malaria P.f]. / Antigénémie HRP-2 et paludisme d'importation à Plasmodium falciparum: comparaison du ParaSight-F et de l'ICT malaria P.f.

Serum levels of HRP-2 antigens against Plasmodium falciparum in 568 venous blood samples collected at two general hospitals were evaluated using the ParaSight-F (Becton-Dickinson) alone (568/568 samples) or in combination (156/568 samples) with the new ICT-Malaria P.f. (ICT-diagnostic). Comparison with the reference method (thin and thick blood smears assessed by two experienced parasitologists) showed that both tests were highly sensitive (93% and 96% respectively) and specific (98% and 98% respectively). The positive predictive values of the two tests were equal (96%) and the negative predicative values were close (96% and 98% respectively). Although both tests provided results within 10 minutes and required no special equipment for interpretation, the ICT-Malaria P.f. test seemed simpler and easier to use than the ParaSight-F test. The ParaSight-F test alone was used to monitor serum antigen levels after treatment in 24 patients. Antigen levels remained positive for at least three days after disappearance of circulating parasites (range: 3 to 28 days). Evaluation of serum levels of HRP-2 antigens can be useful for emergency diagnosis, especially in patients with low circulating parasite levels. The ICT-Malaria P.f. test seems especially suited for in-field use.

[Comparative activity of azithromycin against 100 strains of Neisseria gonorrhoeae]. / Activité comparée de l'azithromycine sur cent souches de Neisseria gonorrhoeae.

Azithromycin is a new semisynthetic, acid stable C15 macrolid. In our study, we compared in vitro activity of azithromycin with 6 other antibiotics usually recommended for treatment of N. gonorrhoeae infections: erythromycin, ampicillin, amoxicillin, ceftriaxone, spectinomycin, ciprofloxacin. 100 strains have been selected: 95 clinical strains with different resistance patterns: 60 susceptible to beta-lactams, 25 PPNG, 10 chromosomal decreased susceptibility to beta-lactams. Among these strains, 13 had a decreased susceptibility to erythromycin (MIC: 2 and 4 mg/l) and 5 WHO reference strains: A: spectinomycin resistance, B: wild phenotype, C: chromosomal decreased susceptibility to penicillin and tetracycline, D: chromosomal resistance to penicillin and erythromycin+chromosomal decreased susceptibility to chloramphenicol, E: beta-lactamase producing strain (PPNG) and decreased susceptibility to tetracycline. MICs have been determined by GC agar dilution method. Azithromycin is more active than erythromycin on all N. gonorrhoeae patterns with a two log 10 difference for MIC50 and MIC90 (p < 0.0001). Because of pharmacokinetic properties and activity against Chlamydia trachomatis and urogenital mycoplasms often associated with N. gonorrhoeae, azithromycin is a good alternative for the treatment of genital infections.

[Determination of the susceptibility of staphylococci and enterococci to plycopeptides by the E-test method]. / Détermination de la sensibilité aux glycopeptides des staphylocoques et entérocoques par la méthode E-test.

E-test was evaluated by comparison with the reference agar dilution method on 15 enterococci and 15 staphylococci with variable resistance to glycopeptides and isolated from clinical samples: 15 enterococci with 3 glycopeptide-resistant (2 E. facalis and 1 E. faecium), 1 glycopeptide intermediate E. gallinarum and 11 glycopeptide-sensible E. faecalis; 15 staphylococci with 4 teicoplanine-resistant (1 S. aureus, 1 S. epidermidis and 2 S. hominis), 3 teicoplanin-intermediate (1 S. epidermidis, 2 S. haemolyticus) and 8 teicoplanin sensible strains (6 S. aureus, 1 S. epidermidis and 1 S. hominis). Repeatability (10 determinations by strain) and exactitude were tested for all strains. Our data shows very good results for repeatability and exactitude with the reference method except in the case of coagulase negative staphylococci and teicoplanin. Some technical problems appear in our experience: for staphylococci, a 48 h incubation is necessary to detect teicoplanin-intermediate strains but 24 h is sufficient for enterococci. E-test is expensive, require a strict methodology, but is a good method to detect glycopeptide resistance for staphylococci and enterococci except for coagulase negative staphylococci and teicoplanine.