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The diagnosis of Chlamydia trachomatis infection can be based either on direct detection of the organism or its components or indirectly by measuring antibodies as markers of the individual's response to the infection. The latter is currently of limited value. Neither IgG or IgA antibodies can be used to diagnose current genital infection by Chlamydia trachomatis or to exclude such an infection. There is no solid ground as yet for the use of IgA antibodies as a marker of persistant or unresolved infection. Commercial tests in the Elisa format based on peptides from the MOMP of Chlamydia trachomatis are available and show good specificities and sensitivities. Hsp60 seems to have a unique role in the development of tubal scarring and antibodies to chsp60 could predict tubal factor infertility. Serology is the main diagnostic tool for the diagnosis of Mycoplasma pneumoniae infection. The serologic assays are the complement fixation test (CF), immunofluorescence, the microparticle agglutination and recently EIAs. The CF test is still used for serodiagnosis of Mycoplasma pneumoniae infection because of the sensitivity of 90%. Single titer of >or= 64 are considered to be indicative of recent infection. A number of commercial EIAs have been developped. The difficulty for IgG interpretation is a definition of a cutoff value for discriminating infected and healthy subjects. Most of the IgM assays show good diagnostic sensitivities and are valuable tools for the early diagnosis of Mycoplasma pneumoniae infection in children. There are no wholly satisfactory serological methods for diagnosis of Chlamydia pneumoniae infection. Problems arise from the high background of IgG antibody prevalence, the lack of standardized testing methods.

The in vitro susceptibility of Ureaplasma urealyticum (Uu) and Mycoplasma hominis (Mh) was evaluated in a multicentric study performed in seven hospitals from different geographic areas in France. During a three month period, 324 Uu and 72 Mh clinical isolates were tested using a system ready for use, SIR Mycoplasma (Sanofi Diagnostics Pasteur). For Uu, the percentage of strains intermediate (I) or resistant (R) was as follows: doxycycline (3), minocycline (2.5), lymecycline (6.7), erythromycin (72, most I), josamycin (0.9), clindamycin (88), pristinamycin (0.3), ofloxacin (34, most I). For Mh, the percentage of strains I or R was respectively: doxycycline (2.7), minocycline (5.5), lymecycline (15.2), erythromycin (100), clindamycin (1.4), ofloxacin (2.7), josamycin (0) and pristinamycin (0). Comparable results were observed in the different geographic areas. The frequency of acquired resistances does not justify modifications in the usual treatment of genital mycoplasma infections but leads to monitor their susceptibility to antibiotics.

The authors report on a case of a preterm infant who suffered from pneumonia due to genital mycoplasma infection. Hepatic dysfunction was associated. Tetracyclines were successful.

The in vitro activity of the new difluorinated quinolone sparfloxacin against mycoplasmas was studied comparatively with ofloxacin, doxycycline, and erythromycin. Minimal inhibitory concentrations (MICs) were determined by agar dilution for 21 strains of Mycoplasma pneumoniae (Mp), 20 strains of M. hominis (Mh), 7 strains of M. genitalium (Mg), and 3 strains of M. fermentans (Mf), and by broth dilution for 49 strains of Ureaplasma urealyticum (Uu). Sparfloxacin was very active against all tested mycoplasmas, with the following MICs (microgram/ml): 0.1 for Mp, 0.05-0.1 for Mg, less than or equal to 0.01 for Mh, less than or equal to 0.01-0.05 for Mf, and 0.1-0.5 for Uu. Minimal bactericidal concentration was 1 microgram/ml for Uu. Sparfloxacin was more active than ofloxacin against all the mycoplasmas tested and was the most active compound against Mh and Mf. Erythromycin had the lowest MICs against Mp and Mg. Sparfloxacin exhibited comparable effectiveness against doxycycline-susceptible and doxycycline-resistant strains. Sparfloxacin appears to be one of the most active agents in vitro against mycoplasmas.

We compared the results obtained with two commercially available systems (Diagnostics Pasteur) for the quantitative identification and the antibiotic susceptibility testing of the genital mycoplasmas. Ureaplasma urealyticum and Mycoplasma hominis with established methodologies, i.e. isolation on agar with enumeration by dilutions in broth medium and MIC determinations. The Mycoplasma Plus system, consisting of six cups, was designed for the identification and quantitation of genital mycoplasmas and the detection of yeasts. Used in parallel in 150 clinical specimens, it detected U. urealyticum in 42 out of 43 and M. hominis in 10 out of 11 specimens positive by the established methodology. The SIR Mycoplasma antibiogram, consisting of 16 cups, provided for the testing of 1 or 2 concentrations (micrograms/ml) of each of 8 antibiotics: doxycycline, minocycline and lymecycline (4-8); erythromycin (1-4); josamycin (2-8); clindamycin (2); pristinamycin (2); and ofloxacin (1-4). Using an inoculum of about 10(4)-10(5) organisms/ml, we found that major part of the results was in accord with those obtained with the MIC determined in broth for U. urealyticum and on agar for M. hominis. Strains intermediate or resistant to the tetracyclines were identified. Both systems seemed suitable for clinical laboratory use.

Some new quinolones may be used for the treatment of gonococcal urethritis. U. urealyticum is considered as a potential agent of urethritis. This report describes the in vitro antimicrobial activity of seven quinolones against 45 clinical isolates of U. urealyticum. The MIC's geometric mean is (microgram/ml): rosoxacin (1,74), pefloxacin (4,6), oxolinic acid (9), flumequin (12,12), norfloxacin (15,75), nalidixic acid (27). Pipemidic acid is constantly inactive (greater than 128 micrograms/ml). The results of these susceptibility studies provide support for undertaking clinical evaluations of new quinolones against infections with U. urealyticum.

Mycoplasmas are most often responsible for respiratory and genital infections. At present, diagnosis is carried out by serology for infections caused by M. pneumoniae and by culture for infections due to genital mycoplasmas. For M. pneumoniae, new prospects may lead to a rapid diagnosis, detection by molecular hybridization and immunological detection. Also, the research of specific antibodies should benefit from a better knowledge of the major antigens. Culture of the genital mycoplasmas, U. urealyticum and M. hominis is simple, but the interpretation of their presence is difficult because they may be recovered in a commensal condition. The envisaged advances should lead to a better assessment of their pathogenicity. The role of M. genitalium, a species related to M. pneumoniae recently discovered in respiratory specimens, should be better determined by sensitive techniques developed to distinguish it from M. pneumoniae.

Human pathogen mycoplasmas (Mycoplasma pneumoniae, Mycoplasma hominis, Ureaplasma urealyticum) are intrinsically resistant to antibiotics which inhibit the cell wall biosynthesis (beta-lactams, vancomycin, bacitracin), to polymyxins, rifamycins, sulfonamides, trimethoprim, 5-nitroimidazoles, nitrofurans and to presently available quinolones. These three species are moderately susceptible to aminoglycosides, susceptible to chloramphenicol and highly susceptible to tetracyclines. M. pneumoniae is susceptible to macrolides, lincosamins and streptogramins. M. hominis is resistant to early macrolides (erythromycin, oleandomycin, spiramycin) and susceptible to new macrolides (josamycin, midecamycin, rosaramicin), lincosamins and streptogramins. U. urealyticum is resistant to lincosamins and susceptible to macrolides and streptogramins. Discordant results from various reports can be explained by differences in methods and breakpoint concentration values. In M. pneumoniae species, two strains resistant to macrolides and lincosamins have been described. In M. hominis species, one strain resistant to tetracyclines and another one resistant to tetracyclines and chloramphenicol have been reported. Two to ten percent of U. urealyticum strains are resistant to tetracyclines. These resistances are likely to be plasmid-mediated.

In 79 hospitalized patients in delivery, the search for U. urealyticum was carried out at the level of the vagina, the rim of the placenta, the edge of the PRM orifice and in the throats of newborns, 3 groups were formed: group I: 38 term patients delivering after ARM, group II: 36 patients delivering after 28 weeks, with PRM group III: 5 patients with premature delivery without PRM. The results demonstrate: a highly significant correlation between the women with PRM and those who have a positive vaginal sample; a highly significant correlation between women with PRM and those who have a positive sample on the membranes; a significant correlation between women with PRM and those who have a positive sample on the placenta. The search for ureaplasma would be carried out in case of PRM.

Susceptibility of Mycoplasma pneumoniae (10 strains), Mycoplasma hominis (20 strains) and Ureaplasma urealyticum (100 strains) to minocycline and doxycycline was studied in vitro. Minimal inhibitory concentrations were determined using an agar dilution method for M. pneumoniae and M. hominis and a metabolic inhibition test for U. urealyticum. M. pneumoniae strains were highly susceptible to minocycline and doxycycline (MIC less than or equal to 0.1 mg/l). Among M. hominis strains, 17 were susceptible (MIC less than or equal to 0.1 mg/l), whereas 3 were inhibited only by concentrations ranging from 4 to 16 mg/l. Among the 100 U. urealyticum strains, 95 were inhibited by 4 mg/l minocycline and 94 by 4 mg/l doxycycline. Both antibiotics exhibited similar activities against the three species (same ranges, same mode MICs).

The in vitro activity of new quinolones was evaluated against Mycoplasma pneumoniae (10 strains) and Mycoplasma hominis (approximately equal to 70 strains) by agar dilution, and against Ureaplasma urealyticum (approximately equal to 115 strains) by broth dilution. The static effect of pefloxacin, ofloxacin, ciprofloxacin, enoxacin was investigated for all the strains. Rosoxacin was included in the tests for U. urealyticum and M. hominis. Pefloxacin, ofloxacin, ciprofloxacin and enoxacin were within the same range of sensitivity for M. pneumoniae; the minimal inhibitory concentrations (MICs) of the 10 strains were 1 mg/l for ciprofloxacin, 2 mg/l for pefloxacin, MICs range was (0.05-1 mg/l) for ofloxacin and (0.5-4 mg/l) for enoxacin. Ciprofloxacin was the most active compound against M. hominis; MICs range and mode MICs were respectively in mg/l: (0.1-1) 0.5 for ciprofloxacin, (0.2-2) 0.5 for ofloxacin, (0.5-2) 1 for pefloxacin, (0.5-8) 2 for enoxacin, (2-16) 2 for rosoxacin. Ofloxacin was the most active compound against U. urealyticum; MICs range and mode MICs were respectively in mg/l: (0.2-2) 1 for ofloxacin, (0.1-8) 2 for rosoxacin, (0.5-8) 4 for pefloxacin, (1-16) 4 for ciprofloxacin, (2-32) 8 for enoxacin. No difference could be observed between tetracycline sensitive or resistant strains.

This study was designed to determine if the inhibitory effect of a macrolide (spiramycin) and a tetracycline (minocycline) on the in vitro growth of Mycoplasma pneumoniae is due to a bacteriostatic or a bactericidal activity. M. pneumoniae, strain FH-Liu, susceptible to spiramycin and minocycline was exposed to various inhibitory concentrations of these antibiotics (within the range of 0.5-32 mg/l) for various periods of time (1-9 days). The bactericidal activity was determined by subculturing material from tubes using serial dilution. Spiramycin was bactericidal after 4 days (greater than or equal to 3 log10 decrease of the inoculum) only when high concentrations were used (16 mg/l). Minocycline was bactericidal after 4 days at a concentration of 32 mg/l. These results show a 64-fold difference between minimum inhibitory concentration and minimum bactericidal concentration for spiramycin and a 128-fold difference for minocycline. Our data confirm the bacteriostatic effect of these drugs on M. pneumoniae.

The formation of some urinary tract stones (struvite stones) is known to be related to infection by urease-possessing microorganisms, such as Proteus sp. and some other bacteria. Ureaplasma urealyticum, a genital mycoplasma, contains also urease and is predominantly located in the urogenital tract. Its significance in the production of human urinary stones has not yet been elucidated. In this study, 135 human calculi obtained by surgery were analysed chemically and were cultured for the presence of conventional bacteria and U. urealyticum, 51 were ammonium magnesium phosphate stones and contained Proteus (27), E. coli (4), Staphylococcus epidermidis (3), Streptococcus D (2), Pseudomonas aeruginosa (1), Staphylococcus aureus (1), Corynebacterium (1), Candida albicans (1). U. urealyticum was isolated in one patient, from two different calculi (left and right) taken after an interval of fifteen days. Different bacteria were isolated from other calculi (oxalate, uric acid). This findings suggest that Ureaplasma urealyticum should be looked for in struvite calculi.