Genital mycoplasmas colonise up to 80% of sexually mature women and may invade the amniotic cavity during pregnancy and cause complications. Tetracyclines and fluoroquinolones are contraindicated in pregnancy and erythromycin is often used to treat patients. However, increasing resistance to common antimicrobial agents is widely reported. The purpose of this study was to investigate antimicrobial susceptibility patterns of genital mycoplasmas in pregnant women.
Self-collected vaginal swabs were obtained from 96 pregnant women attending an antenatal clinic in Gauteng, South Africa. Specimens were screened with the Mycofast Revolution assay for the presence of Ureaplasma species and Mycoplasma hominis. The antimicrobial susceptibility to levofloxacin, moxifloxacin, erythromycin, clindamycin and tetracycline were determined at various breakpoints. A multiplex polymerase chain reaction assay was used to speciate Ureaplasma positive specimens as either U. parvum or U. urealyticum.
Seventy-six percent (73/96) of specimens contained Ureaplasma spp., while 39.7% (29/73) of Ureaplasma positive specimens were also positive for M. hominis. Susceptibilities of Ureaplasma spp. to levofloxacin and moxifloxacin were 59% (26/44) and 98% (43/44) respectively. Mixed isolates (Ureaplasma species and M. hominis) were highly resistant to erythromycin and tetracycline (both 97% resistance). Resistance of Ureaplasma spp. to erythromycin was 80% (35/44) and tetracycline resistance was detected in 73% (32/44) of Ureaplasma spp. Speciation indicated that U. parvum was the predominant Ureaplasma spp. conferring antimicrobial resistance.
Treatment options for genital mycoplasma infections are becoming limited. More elaborative studies are needed to elucidate the diverse antimicrobial susceptibility patterns found in this study when compared to similar studies. To prevent complications in pregnant women, the foetus and the neonate, routine screening for the presence of genital mycoplasmas is recommended. In addition, it is recommended that antimicrobial susceptibility patterns are determined.
Pregnant women; Ureaplasma spp.; Mycoplasma hominis; Antimicrobial susceptibilities
Ureaplasma urealyticum organisms (ureaplasmas) were isolated in large numbers (up to 10(8) colour changing units (ccu)/ml) over a period of four years from the urethra of a man with hypogammaglobulinaemia and non-gonococcal urethritis. Elimination of Mycoplasma hominis by antibiotic treatment early in the course of the urethritis did not diminish the severity of his condition, which indicated that this mycoplasma was not a cause. Courses of treatment with tetracyclines, spectinomycin, erythromycin, rosaramicin, and clindamycin on each occasion reduced the numbers of ureaplasma isolated from the urethra and the severity of disease. The organisms were not eliminated, however, sometimes due to the development of antibiotic resistance, and the urethritis recurred. Though netilmicin was not particularly effective in vitro, it was effective clinically, the disease resolving and the organisms disappearing for five months. Recurrence of urethritis, accompanied by epididymitis, was associated this time with the recovery of a different (tetracycline sensitive) ureaplasma strain; the urethritis and epididymitis were treated successfully with a combination of netilmicin and doxycycline. The administration of ureaplasma antiserum did not seem to be instrumental in eradicating the ureaplasmas. The various antibiotics had a greater influence on the mycoplasmas in the urethra than on those in the throat and joints, perhaps because the antibiotics were concentrated in the urogenital tract. The close association between the occurrence of urethritis and the ureaplasmas suggests strongly that they were responsible for it.
Genital ureaplasmas (Ureaplasma urealyticum and Ureaplasma parvum) and mycoplasmas (Mycoplasma genitalium and Mycoplasma hominis) are potentially pathogenic species playing an etiologic role in both genital infections and male infertility. Reports are, however, controversial regarding the effects of these microorganisms infections in the sperm seminological variables. This study aimed at determining the frequency of genital ureplasmas and mycoplasmas in semen specimens collected from infertile men, and at comparing the seminological variables of semen from infected and non-infected men with these microorganisms.
A total of 120 semen samples collected from infertile men were investigated. Semen specimens were examined by in-house PCR-microtiter plate hybridization assay for the presence of genital ureaplasmas and mycoplasmas DNA. Semen analysis was assessed according to the guidelines of the World Health Organization. Standard parametric techniques (t-tests) and nonparametric techniques (Wilcoxon tests) were used for statistical analysis.
The frequency of genital ureaplasmas and mycoplasmas detected in semen samples of infertile men was respectively 19.2% (23/120) and 15.8% (19/120). The frequency of Ureaplasma urealyticum (15%) was higher than that of Mycoplasma hominis (10.8%), Ureaplasma parvum (4.2%) and Mycoplasma genitalium (5%). Mixed species of mycoplasmas and ureaplasmas were detected in 6.7% of semen samples.
Comparison of the parameters of the standard semen analysis between the male partners of the infertile couples with and without genital ureaplasmas and mycoplasmas infection showed that the presence of Mycoplasma hominis DNA in semen samples is associated with low sperm concentration (p = 0.007) and abnormal sperm morphology (p = 0.03) and a negative correlation between sperm concentration and the detection of Mycoplasma genitalium in semen samples of infertile men (p = 0.05). The mean values of seminal volume, pH, vitality, motility and leukocyte count were not significantly related either to the detection of genital mycoplasmas DNA or to the detection of ureaplasmas DNA in semen specimens.
Our results demonstrate that genital mycoplasmas and ureaplasmas seem to be widespread among the male partners of infertile couples in Tunisia. Genital mycoplasmas infections of the male genital tract could negatively influence semen quality. Our results also indicate that PCR-microtiter plate hybridization assay method provides a rapid and effective technique to detect human genital mycoplasmas and ureaplasmas which is useful for etiological and epidemiological studies of these pathogens.
The antibiotic resistance of Mycoplasma mycoides ssp. mycoides strain T1 was investigated. This strain was resistant to high levels (greater than 100 micrograms ml-1) of rifampicin and nalidixic acid. It was sensitive to streptomycin, spectinomycin and novobiocin; however, single step mutants with high levels of resistance (greater than 100 micrograms ml-1) were readily isolated. With erythromycin and tylosin for which the minimum inhibitory concentration (MIC) for the parent strain was less than 0.1 microgram ml-1, mutants resistant to greater than 100 micrograms ml-1 were obtained in two and three steps respectively. The MIC of tetracycline in single step resistant mutants (0.6 microgram ml-1) was tenfold higher than the parent strain, but could not be increased further. There was only a twofold increase in resistance to chloramphenicol in single step mutants. The frequency of resistant mutants varied with the antibiotic and was between 4 X 10(-6) and 2 X 10(-8). The mutation rate to antibiotic resistance to streptomycin, spectinomycin, novobiocin, erythromycin and tylosin was between 3 X 10(-8) and 5 X 10(-9) per cell per generation. There was a fivefold decrease in mutation rate to resistance to 60 micrograms ml-1 streptomycin compared to that to 20 micrograms ml-1.
The susceptibilities of T-mycoplasmas (Ureaplasma urealyticum) to minocycline, demeclocycline, doxycycline, tetracycline, and erythromycin were determined by a direct tube dilution test. T-mycoplasma-positive urine sediments of 105 patients with a history of reproductive failure were used as inocula. Minocycline was found to be the most active of the group of antibiotics commonly used to eradicate T-mycoplasma infection. Based on the median initial minimum inhibitory concentration, minocycline was the lowest with 0.03 μg/ml, followed by demeclocycline and doxycycline with 0.125 μg/ml, tetracycline with 0.25 μg/ml, and erythromycin with 2.0 μg/ml. Six T-mycoplasma isolates which had been cloned three times were also tested for susceptibility to the same five antibiotics. The same susceptibility pattern was found. Strains resistant to high concentrations of all antibiotics occurred. Strong positive correlation was seen in 21 patients between in vitro highly resistant strains and positive posttreatment cultures. These results indicate that empirical treatment of genital mycoplasma infections is not justified. Cultures should be taken pretreatment, susceptibility testing performed prior to treatment, and follow-up cultures done posttreatment.
Background & objectives:
Ureaplasmas have been implicated in a variety of clinical conditions. However, only certain serovars of ureaplasmas are disease associated. Only a few classes of antimicrobial agents are available for the treatment of mycoplasmal infections in humans. Increase of resistance of genital mycoplasmas to antimicrobials has been reported worldwide. The aim of the present study was to determine the occurrence of Ureaplasma serovars in patients with infertility and genital tract infections with polymerase chain reaction (PCR)–based serotyping. The antimicrobial susceptibilities of Ureaplasma spp. and Mycoplasma hominis were also assessed to determine the most suitable treatment strategy.
Sexually active adults (n=147) with symptoms of genital tract infections and 115 infertile women were enrolled. Endocervical swabs from women and urethral swabs from men were subjected to culture and multiplex PCR for detection of genital mycoplasmas. Serotyping of Ureaplasma was done by PCR and antimicrobial susceptibility to doxycycline, azithromycin, josamycin and ofloxacin was done by microbroth dilution method.
Ureaplasma was detected in 25.8 per cent patients with genital tract infections and 20.8 per cent in infertile women. Serovar 3/14 was the most frequent isolate followed by serovar 1 and serovar 6. The majority of Ureaplasma isolates were susceptible to doxycycline (91%) and josamycin (86%) followed by ofloxacin (77%) and azithromycin (71%). All the isolates of M. hominis were uniformly susceptible to doxycycline, josamycin and ofloxacin.
Interpretation & conclusions:
The predominance of Ureaplasma serovar 3/14 suggests their possible pathogenic role in genital tract infections and infertility. For empirical treatment, doxycycline could be the drug of choice for genital mycoplasmas.
Antimicrobial susceptibility; PCR; ureaplasma serovars
The purpose of this study was to determine the susceptibility of various strains of Mycoplasma bovis, Mycoplasma dispar, and Ureaplasma diversum, which are prevalent causes of pneumonia in calves, to 16 antimicrobial agents in vitro. The MICs of the antimicrobial agents were determined by a serial broth dilution method for 16 field strains and the type strain of M. bovis, for 19 field strains and the type strain of M. dispar, and for 17 field strains of U. diversum. Final MICs for M. bovis and M. dispar were read after 7 days and final MICs for U. diversum after 1 to 2 days. All strains tested were susceptible to tylosin, kitasamycin, and tiamulin but were resistant to nifuroquine and streptomycin. Most strains of U. diversum were intermediately susceptible to oxytetracycline but fully susceptible to chlortetracycline; most strains of M. bovis and M. dispar, however, were resistant to both agents. Strains of M. dispar and U. diversum were susceptible to doxycycline and minocycline, but strains of M. bovis were only intermediately susceptible. Susceptibility or resistance to chloramphenicol, spiramycin, spectinomycin, lincomycin, or enrofloxacin depended on the species but was not equal for the three species. The type strains of M. bovis and M. dispar were more susceptible to various antimicrobial agents, including tetracyclines, than the field strains. This finding might indicate that M. bovis and M. dispar strains are becoming resistant to these agents. Antimicrobial agents that are effective in vitro against all three mycoplasma species can be considered for treating mycoplasma infections in pneumonic calves. Therefore, tylosin, kitasamycin, and tiamulin may be preferred over oxytetracycline and chlortetracycline.
The increasing resistance of genital mycoplasmas to tetracycline poses a problem because tetracycline is one of the few antimicrobial agents active against Mycoplasma hominis, Ureaplasma urealyticum, chlamydiae, gonococci, and other agents of genitourinary-tract disease. Since the quinolones are a promising group of antimicrobial agents, the susceptibilities of M. hominis and U. urealyticum to the newer 6-fluoroquinolones were determined by the agar dilution method. Ciprofloxacin, difloxacin, and ofloxacin had good activity against M. hominis, with the MIC for 50% of isolates tested (MIC50) being 1 microgram/ml. Fleroxacin, lomefloxacin, pefloxacin, and rosoxacin had MIC50s of 2 micrograms/ml. Enoxacin, norfloxacin, and amifloxacin had MIC50s of 8 to 16 micrograms/ml, and cinoxacin and nalidixic acid were inactive (MIC50, greater than or equal to 256 micrograms/ml). Overall, the activities of 6-fluoroquinolones for ureaplasmas were similar to those for M. hominis, with MICs being the same or twofold greater. The most active 6-fluoroquinolones against ureaplasmas were difloxacin, ofloxacin, and pefloxacin, with MIC50s of 1 to 2 micrograms/ml. Ciprofloxacin was unusual in that the MIC50 for M. hominis was 1 microgram/ml, whereas the MIC50 for ureaplasmas was 8 micrograms/ml. Since the MIC50s for the most active quinolones approximate achievable concentrations in blood and urine, quinolones have promise in treating mycoplasmal infections.
Genital mycoplasmas are opportunistic bacteria that are associated with undesirable gynaecologic and reproductive events. Mycoplasmas are fastidious bacteria with increasing resistance to routine antimicrobials and often fail to grow on conventional culture methods. The commercial Mycofast Revolution assay permits the phenotypic detection and identification of genital mycoplasmas. Antimicrobial susceptibility testing against five antimicrobial agents with MICs corresponding to the CLSI guidelines can also be performed. This study aimed to compare the new commercially available Mycofast Revolution assay with a multiplex PCR assay.
Self-collected swabs were obtained from pregnant women attending the antenatal clinic of a tertiary academic hospital in Pretoria, South Africa from October 2012 to November 2012. These swabs were used to seed UMMt and modified Amies transport media. The seeded UMMt transported medium was used to inoculate the Mycofast Revolution assay for the identification, enumeration and antimicrobial susceptibility testing of genital mycoplasmas. Following DNA extraction from the modified Amies transport medium, specimens were subjected to a multiplex PCR assay for the detection of genital mycoplasmas.
The Mycofast Revolution kit had a sensitivity and specificity of 77.3% (95% CI: 62.15% to 88.51%) and 80% (95% CI: 28.81% to 96.70%), respectively, against the PCR assay. The positive and negative predictive values were 97.1% (95% CI: 85.03% to 99.52%) and 28.6% (95% CI: 8.57% to 58.08%). Genital mycoplasmas were detected in 71.4% (35/49) of samples with the Mycofast Revolution assay with 49% (24/49) being Ureaplasma spp. and 22.4% (11/49) mixed strains. The multiplex PCR assay had a positivity rate of 89.8% (44/49) for genital mycoplasmas; mixed strains were present in 51% (25/49) of samples, Ureaplasma spp. in 16.3% (8/49) and M. hominis in 22.4% (11/49) of samples.
There was a fair agreement (κ = 0.319) between the Mycofast Revolution assay and the mPCR assay. With the high prevalence rates of genital mycoplasmas, fast and efficient diagnostic methods are imperative to treat infections and minimise complications. The Mycofast Revolution assay is simple to use, has a short turn-around time and interpretation of results are straightforward. This assay circumvents common problems experienced with conventional culture and molecular methods in diagnostic laboratories where skilled personnel are limited and can be used as an alternative diagnostic assay.
Mycoplasma hominis; Ureaplasma spp; Mycofast; Antimicrobial susceptibilities; Multiplex PCR assay
We report herein a survey in which cultures of bovine reproductive tracts for Ureaplasma diversum and mycoplasmas were carried out in order to better understand the role of these organisms in granular vulvitis (GV). Samples cultured were vulvar swabs from clinically normal cows or ones with GV, preputial swabs or raw semen from bulls, and abomasal contents of aborted fetuses.
Ureaplasma diversum was isolated from 104 (43.3%) of 240 dairy cows, 32 (27.1%) of 118 beef cows, 43 (47.2%) of 91 beef heifers, 23 (67.6%) of 34 beef bulls, and three (60%) of five dairy bulls. Mycoplasmas were isolated from 18 (7.5%) dairy cows, two (1.6%) beef cows, three (8.8%) beef bulls, and one dairy bull. No isolation was made from 97 aborted fetuses. For 65 dairy cows and 30 beef heifers with vulvar lesions, the isolation rates for ureaplasmas of 62.5% and 69.7%, respectively, were significantly higher (X2) than those for normal animals (37.5% and 30.3%). On immunofluorescent serotyping of 137 of the 205 isolates, there were 66 in serogroup C (strain T44), 18 in serogroup B (strain D48), eight in serogroup A (strain A417 or strain 2312), 14 cross-reacting, and 31 that were not identified. It was concluded that U. diversum is commonly present in the lower reproductive tract of beef/dairy cattle in Saskatchewan and is associated with granular vulvitis.
Mycoplasma bovis is a worldwide pathogen, causative agent of pneumonia, mastitis, arthritis, and a variety of other symptoms in cattle. The economic losses due to mycoplasma pneumonia could be reduced by antibiotic treatment. The aim of the present study was to determine the in vitro susceptibility of M. bovis strains isolated from cattle in Hungary to eleven antibiotics.
Minimal inhibitory concentration (MIC) values of 35 M. bovis strains collected from different parts of Hungary between 2010 and 2013 were determined by the microbroth dilution method. Strains with high MIC values were found in the case of all applied antibiotics. The most effective antibiotics tested in vitro were fluoroquinolones (MIC90 danofloxacin 0.312 μg/ml, enrofloxacin 0.312 μg/ml, marbofloxacin 0.625 μg/ml). Our results confirm the observations of increasing MIC values to antibiotics commonly used in the therapy of mycoplasma infections, primarily to tetracyclines; tetracycline (MIC90 16 μg/ml) and oxytetracycline (MIC90 ≥ 64 μg/ml) and macrolides; tylosin (MIC90 ≥ 128 μg/ml) and tilmicosin (MIC90 ≥ 128 μg/ml). The growth of many M. bovis strains was not inhibited by gentamicin (MIC90 8 μg/ml), spectinomycin (MIC90 ≥ 256 μg/ml), florfenicol (MIC90 8 μg/ml) or lincomycin (MIC90 ≥ 64 μg/ml).
Our results emphasize the necessity of periodic testing for antibiotic susceptibility in this geographic region. Based on our in vitro examinations, fluoroquinolones could be the most effective drugs for the therapy of M. bovis infections in Hungary. However, current antimicrobial use policies have to be taken into account to avoid further antibiotic resistance development and to reserve fluoroquinolones for the treatment of severe infections which have responded poorly to other classes of antimicrobials.
Antibiotic resistance; MIC; Fluoroquinolones; Microbroth dilution; Mycoplasma bovis
Ureaplasma respiratory tract colonization is a risk factor for bronchopulmonary dysplasia (BPD) in preterm infants, but whether Ureaplasma isolates from colonized infants can form biofilms is unknown. We hypothesized that Ureaplasma isolates vary in capacity to form biofilms that contribute to their antibiotic resistance and ability to evade host immune responses. Study objectives were to 1) determine the ability of Ureaplasma isolates from preterm neonates to form biofilms in vitro; 2) compare the susceptibility of the sessile and planktonic organisms to azithromycin and erythromycin; and 3) determine the relationship of biofilm-forming capacity in Urea-plasma isolates and the risk for BPD.
Forty-three clinical isolates from preterm neonates and five ATCC strains were characterized for their capacity to form biofilms in vitro and antibiotic susceptibility was performed on each isolate pre- and post-biofilm formation.
Forty-one (95%) clinical and 4 of 5 (80%) ATCC isolates formed biofilms. All isolates were more susceptible to azithromycin (Minimum Inhibitory Concentration, MIC50 2 μg/mL) than erythromycin (MIC50 4 μg/mL), and biofilm formation did not significantly affect antibiotic susceptibility for the 2 tested antibiotics. The MIC50 and minimum biofilm inhibitory concentrations (MBIC50) for U. urealyticum clinical isolates for azithromycin were higher than for MIC50 and MBIC50 for U. parvum isolates. There were no differences in MIC or MBICs among isolates from BPD infants and non-BPD infants.
Capacity to form biofilms is common among Ureaplasma spp. isolates, but biofilm-formation did not impact MICs for azithromycin or erythromycin.
Ureaplasma parvum; Ureaplasma urealyticum; bacterial biofilms; erythromycin; azithromycin; bronchopulmonary dysplasia
The new pleuromutilin derivative 81.723 hfu is extremely active against gram-positive organisms such as streptococci, staphylococci, and against mycoplasmas. A number of Shigella, Klebsiella, and Escherichia coli strains were also found to be quite susceptible to this new agent, whereas other gram-negative organisms like Pseudomonas aeruginosa, Proteus species, and Alcaligenes faecalis proved to be naturally resistant to 81.723 hfu. The new compound acts bacteriostatically. Bactericidal effects have been observed only at concentrations which are 100-fold higher than the minimal inhibitory concentrations. The new antibiotic is well tolerated in all animal species tested so far and has been successfully used in the treatment of experimental infections with gram-positive organisms and with mycoplasmas in mice and rats. Resistance against this new compound arose gradually in all microorganisms investigated. It is noteworthy that the rate at which resistance against 81.723 hfu emerged in mycoplasmas (Mycoplasma gallisepticum and Mycoplasma hyorhinis) was significantly slower than the corresponding rate at which resistance against tylosin tartrate appeared. Mycoplasma strains which became insensitive to 81.723 hfu were also resistant to tylosin tartrate, whereas mycoplasmas which developed resistance against tylosin tartrate, although less sensitive to 81.723 hfu than wild-type strains, were still eliminated by this drug. In a strain of Klebsiella pneumoniae, complete cross-resistance was observed between the pleuromutilin derivative on one hand and lincomycin and erythromycin on the other. Modest degrees of cross-resistance were also observed with chloramphenicol. However, it appears unlikely that the latter phenomenon is sufficiently pronounced to affect treatment with either antibiotic.
A combination of lincomycin-spectinomycin-tylosin was tested against several strains of mycoplasmas and acholeplasmas as might be encountered in bovine semen and shown to be effective against them. This combination as well as minocin , rosaramicin, rosoxacin, tiamulin, gentamicin and declomycin were tested in vitro against 58 isolates of ureaplasma from the bovine urogenital tract. The lincomycin-spectinomycin-tylosin combination, minocin , rosaramicin, tiamulin and declomycin were quite active, while rosoxacin and gentamicin were much less active against the test strains.
A simple, direct broth-disk test, utilizing urine sediment as the inoculum and impregnated paper disks as the source of antibiotic, was developed and used to test the susceptibility of 54 isolates of Ureaplasma urealyticum (T-strain mycoplasmas) to minocycline, doxycycline, demeclocycline, tetracycline, and erythromycin. The concentration of each antibiotic was calculated to approximate the attainable blood level. Resistance or susceptibility to each antibiotic was determined by growth, indicated by a color change of the medium in each tube, comparable to that of a control culture without antibiotic. Of the 54 T-mycoplasmas tested, 46 (85.2%) were inhibited by 1 μg of minocycline per ml, 45 (83.3%) were inhibited by 1 μg of doxycycline per ml, 38 (72.2%) were inhibited by 1 μg of demeclocycline per ml, 18 (33.3%) were inhibited by 1 μg of tetracycline per ml, and only 2 (3.7%) were inhibited by 3 μg of erythromycin per ml. Seven (13%) of the 54 T-mycoplasmas tested were resistant to all five antibiotics. There was good correlation between results obtained by this direct broth-disk method and minimal inhibitory concentrations obtained by the direct broth dilution method.
Bull semen is commonly contaminated with mycoplasmas. To determine the source of contamination, semen and the genital tracts of 45 artificial insemination bulls were cultured for these organisms. The results indicate that mycoplasmas colonize the prepuce and the distal part of the urethra. Only rarely were they found in the ampullae or seminal vesicles. In 92% of the bulls with contaminated semen the same Mycoplasma species or Ureaplasma diversum was isolated from the prepuce and urethral orifice as was found in the semen. This suggests that the prepuce and distal urethra is the source of contamination. Colonization of the genital tracts with Mycoplasmas or U. diversum was not associated with histological changes.
Mycoplasma; ureaplasma; genital tract; semen; artificial insemination; microbial colonization
The in vitro susceptibilities of 103 Mycoplasma pneumoniae isolates, 14 Mycoplasma hominis isolates, 12 Mycoplasma fermentans isolates, and 24 Ureaplasma species to ABT-773, an investigational ketolide, and seven other agents were determined. For M. pneumoniae, the ABT-773 MIC at which 90% of isolates are inhibited (MIC90; ≤0.001 μg/ml) was comparable to those of azithromycin, clarithromycin, and erythromycin and at least 128-fold lower than those of levofloxacin, gatifloxacin, moxifloxacin, and doxycycline. For M. fermentans, the ABT-773 MIC90 (≤0.008 μg/ml) was 2- to 128-fold lower than those of all other agents tested. For M. hominis, the ABT-773 MIC90 (0.031 μg/ml) was equivalent to that of moxifloxacin, 2-fold lower than those of gatifloxacin and clindamycin, and 16-fold lower than that of levofloxacin. ABT-773 was equally active against doxycycline-susceptible and doxycycline-resistant organisms. The ABT-773 MICs (0.016 μg/ml) for Ureaplasma species were the lowest of those of any drug tested. The MIC90 was 4- to 64-fold lower than those of clarithromycin, azithromycin, and erythromycin and ≥16-fold lower than those of all three fluoroquinolones. Minimal bactericidal concentrations determined for a subgroup of organisms were ≤0.063 μg/ml for M. pneumoniae and 0.25 μg/ml for M. fermentans, but they were several dilutions higher for M. hominis and Ureaplasma spp. ABT-773 has great potential for further study for the treatment of infections due to mycoplasmas and ureaplasmas.
Meatal swabs were obtained at intervals over 1 year from 23 men in the Antarctic. A 5-day course of tetracycline was given to twelve of them. In retrospect it was found that the antibiotic had been received by two men who were harbouring ureaplasmas, one of whom also had M. hominis. After treatment, these organisms were not found in any of the swabs taken over the next year, except in a swab from one of the men following sexual contact after this time. One of the twelve men developed N.S.U. just before arriving in the Antarctic. He responded clinically to a shorter course of tetracycline and ureplasmas were not recovered from a meatal swab immediately thereafter. However, without further sexual contact, ureaplasmas and disease recurred about a month later. This time, after a 5-day course of tetracycline, disease was not seen, and ureaplasmas were not isolated, over the next year. In contrast, ureaplasmas were isolated consistently over a year from two men who were not given the antibiotic. The evidence strongly suggests that, under natural conditions, the most likely cause of mycoplasmas, particularly ureaplasmas, recurring in the genital tract after apparently adequate tetracycline therapy, is re-infection as a result of sexual re-exposure.
Mammalian cell culture systems were maintained free of mycoplasmas by using a 3-day agar plate test as a weekly routine to monitor the conditions of the cells. If contaminated cell cultures were found, they were discarded and replaced from a pleuropneumonia-like organism (PPLO)-free cell bank. PPLO-free lines were established by treatment with various antibiotics. The KB cell line was freed of mycoplasmas by treatment for 1 week with a mixture of chlortetracycline, kanamycin, and chloramphenicol. L-929 cells were cleared of contamination with either spectinomycin or tylosin, and a synovial cell line was cleared with lincomycin or tylosin. Each cell line, after eradication of the contaminant, was stored in liquid nitrogen. A number of agents were tested to determine minimal inhibitory concentration against three known and three unidentified mycoplasmas. Chlortetracycline and tetracycline were found to be highly active against all strains, whereas tylosin, spectinomycin, and lincomycin, though less active, were equally useful because of their low toxicity against cells. Kanamycin was highly active against three strains, but inactive at high levels against the KB cell contaminants. A disc plate test was used to check isolated cell contaminants for sensitivity to various agents.
Ureaplasma urealyticum organisms (ureaplasmas) and Mycoplasma hominis organisms (mycoplasmas) were sought in mid-stream urines collected from 200 men and 200 women attending hospital with conditions of a non-venereal nature. In addition, the urines from 100 male and 100 female healthy volunteers were examined. Overall, ureaplasmas were isolated four times more often than mycoplasmas. In individuals less than 50 years of age, the organisms were found in about 20% of men and about 40% of women. In individuals 50 years or older, they were found about one-third to one-half as frequently. Centrifugation of urine and examination of the resuspended deposit did not increase the isolation rates. In men, the numbers of organisms in the urine were usually small (less than or equal to 10(3) c.c.u./ml) with less than tenfold more in the urine of women. The occurrence of 51- greater than 1000 leucocytes per mm3 in some of the urines was not associated with either the presence or an increased number of ureaplasmas/mycoplasmas, whereas they were associated with the presence of 10(5) or more bacteria/ml. The significance of these findings in the context of defining the role of ureaplasmas/mycoplasmas in genital-tract disease is discussed.
To assess the prevalence of bacterial strains and fungal strains infecting the vaginal tract and test their sensitivity to antibiotics in women attending Saint Camille Medical Centre in Ouagadougou.
From January 2008 to December 2009, a total of 2 000 vaginal swabs were cultivated for bacterial and fungal identification and isolation. Furthermore, bacterial strains were tested for their susceptibility to several antibiotics used in routine in the centre.
The results revealed that microbial isolation and identification was attempted for 1 536/2 000 sample, a positivity rate of 76.80%. Candida albicans (48.76%), followed by Escherichia coli (16.67%), Streptococcus agalactiae (8.14%) and Staphylococcus aureus (7.55%) were the major agents of genital tract infections in patients. Mycoplasma hominis and Ureaplasma urealyticum combined accounted for less than 7%. Trichomonas vaginalis was identified in 1.04% cases. The antimicrobial tests revealed that the microorganisms developed resistance to several antibiotics including beta lactams. However, antibiotics such as cefamenzol, ciprofloxacin and norfloxacin were still active on these bacteria.
The results reveal that many sexually active women are infected by one or more microbial pathogens, probably because of the lack of hygiene or the adoption of some risky behaviors, such as not using condoms or having multiple sexual partners. Efforts should be made to address these points in the country.
Bacteria; Genital infections; Antibiotics; Mycoplasma; Fungal strain; Antimicrobial resistance; Abnormal vaginal discharge; Vaginal infection
The in vitro activities of two investigational quinolones, sparfloxacin (previously designated AT 4140) and PD 127391, were determined for 30 strains each of Mycoplasma pneumoniae, Mycoplasma hominis, and Ureaplasma urealyticum and compared with those of ciprofloxacin, tetracycline, clindamycin, and erythromycin. Erythromycin was the most active compound against M. pneumoniae (maximum MIC, less than 0.008 microgram/ml). PD 127391 (MICs, less than 0.008 to 0.031 microgram/ml), sparfloxacin (MICs, less than 0.008 to 0.25 microgram/ml), clindamycin (MICs, less than 0.008 to 0.5 microgram/ml), and tetracycline (MICs, 0.063 to 0.25 microgram/ml) were superior to ciprofloxacin (MICs, 0.5 to 2 microgram/ml). Sparfloxacin and PD 127391 were active against M. hominis (MICs, less than 0.008 to 0.031 microgram/ml for each) at concentrations comparable to those of clindamycin (MICs, less than 0.008 to 0.063 microgram/ml) and at concentrations lower than those of ciprofloxacin (MICs, 0.125 to 0.5 microgram/ml). As expected, M. hominis was resistant to erythromycin (MICs, 32 to greater than or equal to 256 micrograms/ml). For U. urealyticum, PD 127391 (MICs, 0.031 to 0.5 microgram/ml) and sparfloxacin (MICs, 0.063 to 1 microgram/ml) were superior to erythromycin (MICs, 0.25 to 4 micrograms/ml), ciprofloxacin (MICs, 0.5 to 8 micrograms/ml), and clindamycin (MICs, 0.25 to 64 micrograms/ml. Both new quinolones were equally active against tetracycline-susceptible as well as resistant strains of M. hominis and U. urealyticum. The possible influence of medium components and/or pH on MICs was evaluated by testing a Staphylococcus aureus reference strain with each antibiotic in SP-4 broth and 10-B broth and comparing the results with published MICs for this strain. MICs determined in 10-B broth for erythromycin were affected most. This study shows that the activities of sparfloxacin and PD 127391 are similar to one another and comparable or superior to those of other drugs used to treat mycoplasmal infections. The MICs of both new quinolones were consistently 2 to several dilutions lower than those of ciprofloxacin for each species.
Ureaplasma, spp. Mycoplasma genitalium, and Mycoplasma hominis are associated with infection of the genitourinary tract, reproductive failure, and neonatal morbidity and mortality. We have developed a multiplex PCR for the detection of these Mycoplasmatales in a single amplification reaction. The analytical sensitivities of this assay were 10.8, 10.8, and 8.8 CFU for each organism, respectively. This multiplex PCR was compared to culture on 26 cervical swabs, 2 vaginal swabs, 4 female urine specimens, 49 semen samples, 2 male urine specimens, and 1 nonspecified sample. A total of 21 specimens were culture positive (25%); 17 of these were PCR positive. An additional 11 specimens were PCR positive but culture negative. Of the 21 culture-positive specimens, 17 (81%) grew Ureaplasma spp. and 4 (19%) grew Mycoplasma spp. Of the 28 PCR-positive specimens, Ureaplasma spp. was detected in 23 (82%), M. hominis was detected in 3 (11%), and both were detected in 2 (7%). In a confirmatory analysis, all samples were tested by amplification of a second target of the ureaplasma genome. True-positive cases were defined as a positive result by culture or by both amplification assays. The multiplex PCR detected organisms in 26 of the 30 true-positive specimens, as well as in 2 other specimens. Based on a 36% prevalence of infection, the sensitivity, specificity, and positive and negative predictive values of multiplex PCR analyses were 87, 96, 94, and 93%, respectively. Multiplex PCR offers a rapid, sensitive, and easy method to detect genital mycoplasmas.
Objective: The involvement of the genital mycoplasmas Ureaplasma urealyticum
and Mycoplasma hominis in complications of pregnancy has remained
controversial especially because these microorganisms are frequent colonizers of the
lower genital tract. Recovery of bacteria from the placenta appears to be the sole technique
to represent a true infection and not vaginal contamination. Therefore, we investigated the
presence of genital mycoplasmas, aerobic and anaerobic bacteria, and fungi in human
placentas and evaluated their association with morbidity and mortality of pregnancy.
Methods: We cultured placentas from 82 women with complicated
pregnancies. One hundred placentas from women with uncomplicated pregnancies were
evaluated as controls. When possible, placentas were examined histologically for presence
Results: Microorganisms were recovered from 52% of the placentas
of complicated pregnancies and U. urealyticum was the microorganism isolated most
frequently from the placenta. A significant association between positive mycoplasma
culture of the placenta and complication of pregnancy was found, and chorioamnionitis
was positively related to isolation of mycoplasmas.
Conclusions: These data suggest that genital mycoplasmas are
able to infect the human placenta where they can cause chorioamnionitis.
This infection of the placenta by genital mycoplasmas is related to preterm birth and
fatal outcome of pregnancy.
A bioassay was developed to measure the minimum concentration of an antimicrobial drug that disrupts the colonization resistance mediated by model human intestinal microbiota against Salmonella invasion of Caco-2 intestinal cells. The bioassay was used to measure the minimum disruptive concentrations (MDCs) of drugs used in animal agriculture. The MDCs varied from 0.125 μg/ml for some broad-spectrum antimicrobial drugs (e.g., streptomycin) to 16 μg/ml for drugs with limited spectra of antimicrobial activity (e.g., lincomycin). The acceptable daily intake (ADI) residue concentration calculated on the basis of the MDCs were higher for erythromycin, lincomycin, and tylosin than the ADI residue concentrations calculated on the basis of the MICs. The MDC-based ADI values for apramycin, bacitracin, neomycin, novobiocin, penicillin G, streptomycin, tetracycline, and vancomycin were lower than the reported MIC-based ADI values. The effects of antimicrobial drugs at their MDCs on the bacterial composition of the microbiota were observed by denaturing gradient gel electrophoresis of 16S rRNA sequences amplified by PCR. Changes in the population composition of the model colonization resistance microbiota occurred simultaneously with reduced colonization resistance. The results of this study suggest that direct assessment of the effects of antimicrobial drugs on colonization resistance in an in vitro model can be useful in determining ADI values.