[Determination of Gene Mutations Associated with Macrolide and Fluoroquinolone Resistance in Patients Infected with Mycoplasma genitalium].

Abstract

A sexually transmitted bacterium, Mycoplasma genitalium has varying rates of reported resistance to macrolide and some fluoroquinolone group antimicrobials recommended for the treatment of its infections. It is currently recommended that the treatment of these must be planned according to macrolide resistance status. The aim of this study was to determine the presence of macrolide resistance associated mutations (MRM) and fluoroquinolone resistance associated mutations (QRM) in patients infected with M.genitalium. Sixty-one patients who were ≥ 18 years old, presented to our outpatient clinic between March 2017-March 2022, had symptoms of urethritis/cervicitis according to the Centers for Disease Control and Prevention definition were included in the study. By nucleic acid amplification test (NAAT), the presence of M.genitalium (Mycoplasma-Ureaplasma-OSR for BD MAX, BioGX, the Netherlands) as well as Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis (BDMAX system, BD Diagnostics, USA) in the first stream urine samples was determined. Patients' age, gender, sexual orientation if indicated, diagnostic test results for human immunodeficiency virus (HIV) and syphilis, history of antibiotic use in the last three months, presence of concomitant microorganisms detected by NAAT and urine culture results of the symptomatic period were also recorded. Urine samples in which M.genitalium was detected were stored at -80 °C until the study day. On the study day, they were thawed and a modified real-time polymerase chain reaction (Rt-PCR) test was performed targeting the V region (147 bp) of the 23S rRNA gene for MRM and gyrA (nucleotides 172-402), gyrB (nucleotides 1256-1480), parC (nucleotides 164-483) and parE (nucleotides 1210-1489) gene regions for QRM. IBM SPSS 25 (IBM Inc., Armonk, NY, USA) software was used for descriptive statistical analysis of the patient data. Of the patients; 49 were male, 12 were female. The age range was 20-57 years. Sexual orientation of 15 (30.6%) male patients was men who have sex with men (MSM). Sixteen (26.2%) were individuals living with HIV and 14 (87.5%) were MSM. Four patients had previous syphilis infection. By NAAT, a second microorganism was present in 30 patients with M.genitalium; Ureaplasma urealyticum in 27 (90%), C.trachomatis in two (6.7%) and N.gonorrhoeae in one (3.3%) patient. Urine cultures performed in 42 (68.8%) of 61 patients during the symptomatic period yielded Lactobacillus delbrueckii in one patient. Eighteen (29.5%) patients had a history of antimicrobial use in the last three months. Macrolide resistance associated mutations was detected in 45 (73.8%) and QRM in 20 (32.8%) of M.genitalium infected individuals. Of those with MRM, 17 (37.8%) had concurrent QRM. Macrolide resistance associated mutations were detected at positions A2071G (75.6%) and A2072G (24.4%) in the 23S rRNA gene. The presence of QRM was detected in parC (85%) and gyrA regions (15%). C234T mutation in parC was detected in nine patients (45%), C184T in four, A248T in three and A248A in one, while A288G mutation in gyrA was detected in two patients and G285T mutation in one. Chi-square test showed no significant correlation between the presence of mutations associated with resistance and MSM, HIV/syphilis infection status and antimicrobial use in the last three months (p> 0.05). To the best of our knowledge, our study is the first study on antimicrobial resistance of M.genitalium in Türkiye and emphasizes the importance of macrolide resistance in symptomatic patients infected with M.genitalium. Further studies are needed for the clinical significance of mutations associated with fluoroquinolone resistance. Determination of antimicrobial resistance in M.genitalium diagnostic tests will be useful in terms of guiding treatment and preventing inappropriate treatment approaches in the early period.