Antibiotic resistance in Ureaplasma urealyticum/Ureaplasma parvum and Mycoplasma hominis is an issue of increasing importance. However, data regarding the susceptibility and, more importantly, the ...clonality of these organisms are limited. We analyzed 140 genital samples obtained in Bern, Switzerland, in 2014. Identification and antimicrobial susceptibility tests were performed by using the Mycoplasma IST 2 kit and sequencing of 16S rRNA genes. MICs for ciprofloxacin and azithromycin were obtained in broth microdilution assays. Clonality was analyzed with PCR-based subtyping and multilocus sequence typing (MLST), whereas quinolone resistance and macrolide resistance were studied by sequencing gyrA, gyrB, parC, and parE genes, as well as 23S rRNA genes and genes encoding L4/L22 ribosomal proteins. A total of 103 samples were confirmed as positive for U. urealyticum/U. parvum, whereas 21 were positive for both U. urealyticum/U. parvum and M. hominis. According to the IST 2 kit, the rates of nonsusceptibility were highest for ciprofloxacin (19.4%) and ofloxacin (9.7%), whereas low rates were observed for clarithromycin (4.9%), erythromycin (1.9%), and azithromycin (1%). However, inconsistent results between microdilution and IST 2 kit assays were recorded. Various sequence types (STs) observed previously in China (ST1, ST2, ST4, ST9, ST22, and ST47), as well as eight novel lineages, were detected. Only some quinolone-resistant isolates had amino acid substitutions in ParC (Ser83Leu in U. parvum of serovar 6) and ParE (Val417Thr in U. parvum of serovar 1 and the novel Thr417Val substitution in U. urealyticum). Isolates with mutations in 23S rRNA or substitutions in L4/L22 were not detected. This is the first study analyzing the susceptibility of U. urealyticum/U. parvum isolates in Switzerland and the clonality outside China. Resistance rates were low compared to those in other countries. We hypothesize that some hyperepidemic STs spread worldwide via sexual intercourse. Large combined microbiological and clinical studies should address this important issue.
The comparison of the genomes of two very closely related human mucosal
pathogens, Mycoplasma genitalium and Mycoplasma pneumoniae,
has helped define the essential functions of a self-replicating ...minimal cell,
as well as what constitutes a mycoplasma. Here we report the complete sequence
of a more distant phylogenetic relative of those bacteria, Ureaplasma urealyticum
(parvum biovar), which is also a mucosal pathogen of humans. It
is the third mycoplasma to be sequenced, and has the smallest sequenced prokaryotic
genome except for M. genitalium. Although the U. urealyticum
genome is similar to the two sequenced mycoplasma genomes,
features make this organism unique among mycoplasmas and all bacteria. Almost
all ATP synthesis is the result of urea hydrolysis, which generates an energy-producing
electrochemical gradient. Some highly conserved eubacterial enzymes appear
not to be encoded by U. urealyticum, including the cell-division protein
FtsZ, chaperonins GroES and GroEL, and ribonucleoside-diphosphate reductase.
U. urealyticum has six closely related iron transporters, which apparently
arose through gene duplication, suggesting that it has a kind of respiration
system not present in other small genome bacteria The genome is only 25.5%
G+C in nucleotide content, and the G+C content of individual genes may predict
how essential those genes are to ureaplasma survival.
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 (AZI) and erythromycin; and (3) determine the relationship of biofilm-forming capacity in Ureaplasma isolates and the risk for BPD.
Forty-three clinical isolates from preterm neonates and 5 American Tissue Culture Collection strains were characterized for their capacity to form biofilms in vitro, and antibiotic susceptibility was performed on each isolate prebiofilm and postbiofilm formation.
Forty-one (95%) clinical and 4 of 5 (80%) American Tissue Culture Collection isolates formed biofilms. All isolates were more susceptible to AZI (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 Ureaplasma urealyticum clinical isolates for AZI were higher than for MIC50 and MBIC50 for Ureaplasma 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 AZI or erythromycin.
Background. Bacterial vaginosis (BV) is a poorly detected public health problem that is associated with preterm delivery and for which no reliable diagnostic tool exists. Methods. Molecular analysis ...of 231 vaginal samples, classified by Gram stain–based Nugent score, was used to propose molecular criteria for BV; these criteria were prospectively applied to 56 new samples. A quantitative molecular tool targeting 8 BV-related microorganisms and a human gene was developed using a specific real-time polymerase chain reaction assay and serial dilutions of a plasmid suspension. The targeted microorganisms were Gardnerella vaginalis, Lactobacillus species, Mobiluncus curtisii, Mobiluncus mulieris, and Candida albicans (which can be identified by Gram staining), as well as Atopobium vaginae, Mycoplasma hominis, and Ureaplasma urealyticum (which cannot be detected by Gram staining). Results. With use of the Nugent score, 167 samples were classified as normal, 20 were classified as BV, and 44 were classified as intermediate. Except for U. urealyticum, M. mulieris, and Lactobacillus species, DNA of the tested bacteria was detected more frequently in samples demonstrating BV, but the predictive value of such detection was low. The molecular quantification of A. vaginae (DNA level, ⩾108 copies/mL) and G. vaginalis (DNA level, ⩾109 copies/mL) had the highest predictive value for the diagnosis of BV, with excellent sensitivity (95%), specificity (99%), and positive (95%) and negative (99%) predictive values; 25 (57%) of the samples demonstrating intermediate flora had a BV profile. When applied prospectively, our molecular criteria had total positive and negative predictive values of 96% and 99%, respectively. Conclusions. We report a highly reproducible, quantitative tool to objectively analyze vaginal flora that uses cutoff values for the concentrations of A. vaginae and G. vaginalis to establish the molecular diagnosis of BV.
In this article, we discuss the polymerase chain reaction (PCR)–hybridization assay that we developed for high-throughput simultaneous detection and differentiation of Ureaplasma urealyticum and ...Ureaplasma parvum using one set of primers and two specific DNA probes based on urease gene nucleotide sequence differences. First, U. urealyticum and U. parvum DNA samples were specifically amplified using one set of biotin-labeled primers. Furthermore, amine-modified DNA probes, which can specifically react with U. urealyticum or U. parvum DNA, were covalently immobilized to a DNA–BIND plate surface. The plate was then incubated with the PCR products to facilitate sequence-specific DNA binding. Horseradish peroxidase–streptavidin conjugation and a colorimetric assay were used. Based on the results, the PCR–hybridization assay we developed can specifically differentiate U. urealyticum and U. parvum with high sensitivity (95%) compared with cultivation (72.5%). Hence, this study demonstrates a new method for high-throughput simultaneous differentiation and detection of U. urealyticum and U. parvum with high sensitivity. Based on these observations, the PCR–hybridization assay developed in this study is ideal for detecting and discriminating U. urealyticum and U. parvum in clinical applications.
The objective of this study was to analyze the infection rate and drug resistance of Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) in the genitourinary tract of Chinese patients. From ...December 2018 to June 2019, vaginal secretion or urinary secretion of outpatients in our hospital were selected for culture and drug sensitivity analysis of Ureaplasma urealyticum and Mycoplasma hominis. In 4082 Chinese samples, 1567 Mycoplasma were detected, a detection rate of 38.39%, among which 1366 cases were UU single positive, accounting for 33.47%, 15 cases were MH single positive, accounting for 0.36%, 186 cases were UU and MH mixed positive, accounting for 4.56%. The most affected age groups were 21-30 years and 31-40 years, accounting for 19.09 and 15.05%, respectively. The results of drug sensitivity showed that doxycycline, minocycline, josamycin, clarithromycin, and roxithromycin were more sensitive to mycoplasma infection. The distribution of Ureaplasma urealyticum and Mycoplasma hominis in the human genitourinary system and their sensitivity to antibiotics is different for sex and age groups.
Escalating levels of antibiotic resistance in mycoplasmas, particularly macrolide resistance in
and
, have narrowed our antibiotic arsenal. Further, mycoplasmas lack a cell wall and do not synthesize ...folic acid, rendering common antibiotics, such as beta-lactams, vancomycin, sulfonamides, and trimethoprim, of no value. To address this shortage, we screened nitroxoline, triclosan, and a library of 20 novel, halogenated phenazine, quinoline, and NH125 analogues against
species and
clinical isolates from urine. We tested a subset of these compounds (
= 9) against four mycoplasma type strains (
,
,
, and
) using a validated broth microdilution or agar dilution method. Among 72
species clinical isolates, nitroxoline proved most effective (MIC
, 6.25 µM), followed by an
-arylated NH125 analogue (MIC
, 12.5 µM). NH125 and its analogue had significantly higher MICs against
isolates than against
isolates, whereas nitroxoline did not. Nitroxoline exhibited bactericidal activity against
isolates but bacteriostatic activity against the majority of
isolates. Among the type strains, the compounds had the greatest activity against
and
, with 8 (80%) and 5 (71.4%) isolates demonstrating MICs of ≤12.5 µM, respectively. Triclosan also exhibited lower MICs against
and
Overall, we identified a promising range of quinoline, halogenated phenazine, and NH125 compounds that showed effectiveness against
and
and found that nitroxoline, approved for use outside the United States for the treatment of urinary tract infections, and an
-arylated NH125 analogue demonstrated low MICs against
species isolates.
Ureaplasma respiratory tract colonization is associated with bronchopulmonary dysplasia (BPD) in preterm infants. Whether the 4 Ureaplasma parvum and 10 Ureaplasma urealyticum serovars differ in ...virulence is unknown. This study was conducted to determine the distribution of Ureaplasma serovars in respiratory secretions of a prospective cohort of preterm infants and to assess whether any of the serovars are associated with BPD.
Serial endotracheal and/or nasopharyngeal aspirates were obtained for Ureaplasma culture and PCR from 136 infants of gestational age <33 weeks. All positive samples were speciated and serovars were determined by real-time PCR.
A total of 51 (37.5%) infants were Ureaplasma-positive one or more times during the first month of life. Respiratory colonization was inversely related to gestational age. Sixty-five percent of infants <26 weeks compared with 31% infants ≥ 26 weeks were culture or PCR positive. U. parvum was more common (N = 32, 63%) than U. urealyticum (N = 17, 33%); both species were present in 2 samples. Serovars 3 and 6 alone and in combination accounted for 96% U. parvum isolates. U. urealyticum isolates were commonly a mixture of multiple serovars, with serovar 11 alone or combined with other serovars (10/17, 59%) being the most common serovar. No individual species or serovars or serovar mixtures were associated with moderate-to-severe BPD.
U. parvum serovars 3 and 6 and U. urealyticum serovar 11 were the most common serovars detected in respiratory samples from a prospective cohort of preterm infants.
Mycoplasma hominis and Ureaplasma urealyticum may colonize the human genital tract and have been associated with adverse pregnancy outcomes. Chorioamnionitis, spontaneous preterm labour and preterm ...premature rupture of membranes are significant contributors to neonatal morbidity and mortality. However, as these bacteria can reside in the normal vaginal flora, there are controversies regarding their true role during pregnancy and thus the need to treat these organisms.
We review here the recent data on the epidemiology of mycoplasmas and their clinical role during pregnancy. The association of these organisms with preterm labour has been suggested by many observational studies, but proof of causality remains limited. PCR is an excellent alternative to culture to detect the presence of these organisms, but culture allows antibiotic susceptibility testing. Whether antimicrobial treatment of mycoplasma-colonized pregnant patients can effectively reduce the incidence of adverse pregnancy outcomes warrants further investigations.
The role of Mycoplasma spp. and U. urealyticum in adverse pregnancy outcomes is increasingly accepted. However, sole presence of these microorganisms in the vaginal flora might be insufficient to cause pathological issues, but their combination with other factors such as bacterial vaginosis or cervical incompetence may be additionally needed to induce preterm birth.
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