ABSTRACT
Background: Ureaplasma spp. have been implicated in a variety of clinical conditions and certain serovars are likely to be disease-associated. Hence, the ascending trend of Ureaplasma spp. resistance to antimicrobials should deserve more attention. Here we assessed the extent of antimicrobial resistance of Ureaplasma serovars in Tunisia, and investigated the underlying molecular basis. Methods: This study included 101 molecularly typed Ureaplasma spp. clinical strains isolated over a 12-year time period (2005-2017). The antimicrobial susceptibility was tested against nine antibacterial agents using the broth microdilution method. Neighbor-joining tree was constructed to establish the phylogenetic relationships among isolates. Results: We found that all ureaplasma isolates were resistant to ciprofloxacin and erythromycin, intermediately resistant to azithromycin, and susceptible to doxycycline, moxifloxacin and josamycin. Ofloxacin and levofloxacin resistance was found in 73.27 and 17.82%, respectively, while 37.62% of isolates proved resistant to tetracycline. Consequently, we detected an elevated multidrug resistance rate among ureaplasma isolates (37.62%), particularly among serovars 2, 5, 8, and 9 (77.77% overall), as well as serovars 4, 10, 12, and 13 (52.63% overall). In most cases, drug resistance was found to be associated with known molecular mechanisms, yet we have identified two novel mutations in the L22 protein, which might be associated with macrolide-resistance. Conclusion: To our knowledge, this is the first study that reports the widespread expansion of multidrug resistance among Ureaplasma serovars, a finding of importance in terms of both surveillance and antimicrobial usage.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Mutation , Ureaplasma Infections/microbiology , Ureaplasma/classification , Azithromycin/pharmacology , Bacterial Proteins/genetics , Ciprofloxacin/pharmacology , Erythromycin/pharmacology , Female , Humans , Male , Microbial Sensitivity Tests , Phylogeny , Serogroup , Tunisia , Ureaplasma/genetics , Ureaplasma/isolation & purificationABSTRACT
To our knowledge, the phylodistribution of M. hominis clinical strains associated with various pathological conditions of the urogenital tract has not been explored hitherto. Here we analyzed the genetic diversity and phylogenetic relationships among 59 M. hominis Tunisian clinical isolates, categorized as gynecological infections- or infertility-associated pathotypes. For this purpose, we developed an expanded multilocus sequence typing (eMLST) scheme, combining the previously reported multilocus sequence typing (MLST) loci (gyrB, tuf, ftsY, uvrA, gap) with a new selected set of putative virulence genes (p120', vaa, lmp1, lmp3, p60), referred herein to as multi-virulence-locus sequence typing (MVLST) loci. In doing so, M. hominis population was segregated into two distinct genetic lineages, which were differentially associated with each pathotype. Such a clear dichotomy was supported by several phylogenetic and population genetic analysis tools. Recombination was found to take place, but not sufficient enough to break down the overall clonal population structure of M. hominis, most likely as a result of purifying selection, which accommodated the most fit clones. In sum, and owing to the eMLST scheme described herein, we provide insightful data on the phylogenetics of M. hominis, arguing for the existence of genetically differentiable urogenital pathotypes.
