Macrolide-resistant Mycoplasma genitalium infections in Cuban patients: an underestimated health problem.

BACKGROUND: The increasing prevalence of macrolide resistant Mycoplasma genitalium is a major concern worldwide. In Cuba, several cases of clinical treatment failure with 1 g single dose and extended azithromycin regimen have been detected and the aim of the present investigation was to retrospectively determine the prevalence of macrolide-resistance mediating mutations (MRMM) in M. genitalium-positive samples conserved at the Cuban National Reference Laboratory of Mycoplasma Research between 2009 and 2016. METHODS: A total of 280 positive DNA extracts were analysed by a 5' nuclease assay for detection of M. genitalium MRMM. Ten urogenital specimens from patients with azithromycin treatment failure and MRMM were inoculated in Vero cell to obtain the isolates for subsequent determination of antimicrobial susceptibility. RESULTS: The overall prevalence of MRMM was 32%. No MRMM was detected in samples collected between 2009 and 2013 but since 2014 a dramatic increase to 90% (95% CI, 76-96%) in 2016 was seen. Three new M. genitalium isolates were isolated in Vero cell cultures and confirmed phenotypic resistance to macrolides in a cell-culture assisted susceptibility test. Preliminary observations suggest that combination therapy with levofloxacin and doxycycline may represent an affordable option for treatment of macrolide resistant M. genitalium infections. CONCLUSIONS: This investigation showed the rapid emergence and high prevalence of MRMM in M. genitalium-infected patients in Cuba and confirmed the phenotypic resistance in isolates carrying MRMM. We suggest that Cuban guidelines for sexually transmitted infections are modified to include testing for M. genitalium and detection of MRMM in patients with failure of syndromic treatment, to ensure that in these cases, the treatment will be guided by etiologic diagnosis.

Mycoplasma genitalium infections in Cuba: surveillance of urogenital syndromes, 2014-2015.

Mycoplasma genitalium is an emerging sexually transmitted pathogen implicated in urethritis in men and several inflammatory reproductive tract syndromes in women. The prevalence of M. genitalium infections in Cuban patients with urogenital syndromes is unknown. The aim of this study was to analyse the prevalence of M. genitalium infection in sexually-active Cuban men and women with urogenital syndromes as a part of aetiological surveillance of urogenital syndromes in Cuba. Samples from men and women with urogenital syndromes submitted to the Mycoplasma Reference Laboratory for mycoplasma diagnosis from 1 January 2014 to 1 June 2015 were analysed by polymerase chain reaction (PCR) for detection of M. genitalium. A total of 971 samples were received and processed. Of the patients tested, 5.7% (47/824) of women and 27.9% (41/147) of men were positive for M. genitalium. This paper presents the largest study of M. genitalium infections among Cuban patients with urogenital syndromes and is Cuba's first M. genitalium survey. We suggest that M. genitalium should be considered in the Cuban sexually transmitted infection management protocols as an important pathogen, particularly in men.

Antimicrobial Susceptibility Patterns of Recent Cuban Mycoplasma genitalium Isolates Determined by a Modified Cell-Culture-Based Method.

Isolation of Mycoplasma genitalium from clinical specimens remains difficult and few strains are available for antimicrobial susceptibility testing. We describe the antimicrobial susceptibility of M. genitalium strains grown in Vero cell culture with first- and second- line antibiotics, using a modified cell-culture-based method. Macrolide- and -fluoroquinolone resistance determinants were detected by sequencing of the 23S and parC genes, respectively. Seven strains were examined, including three new, genetically distinct M. genitalium strains isolated from endocervical and urethral swab specimens from Cuban patients together with four reference strains isolated from specimens collected from men in Denmark, Sweden and Australia. Azithromycin was the most active drug against two of the Cuban M. genitalium strains with MICs values of 0.008 mg/liter, however, one strain was macrolide resistant with an MIC of >8 mg/liter, and the A2059G resistant genotype. Ciprofloxacin was the least active antimicrobial drug and moxifloxacin was the most active fluoroquinolone against the new clinical strains, although an MIC of 1 mg/l was found for two strains. However, no relevant parC mutations were detected. MICs for tetracyclines were 0.5-4 mg/liter. Although the number of Cuban strains was low, the results suggest that a single-dose azithromycin treatment could be ineffective, and that a second-line treatment with moxifloxacin, should become an option in Cuba. To our knowledge, this is the first report of isolation and antibiotic susceptibility testing of M. genitalium strains from the Latin-American region, and the first detection of macrolide resistance in such strains.