Frequency of clinical manifestations of M. genitalium infection in patients with and without mutations of M. genitalium resistance to antimicrobial drugs

Background. The growing resistance of M. genitalium (MG) to antimicrobial drugs (AMDs) is an important problem. Objective. To determine a possible influence of MG resistance mutations on clinical course of the disease considering a bacterial load of the pathogen. Material and methods. A number of patients equal 492 were examined in the Moscow Scientific Center of Dermatovenereology and Cosmetology in 2021—2023. The presence and concentration of MG DNA were identified in scraping/secretion from the mucous membrane of the urogenital tract organs by real-time PCR. MG mutations associated with resistance to macrolides (V domain of 23S rRNA gene) and fluoroquinolones (parC gene) were identified by sequencing. Results. A high mutation frequency of MG resistance to AMDs (overall rate was 46%, resistance to macrolides was 20%, to fluoroquinolones was13%, combined was 13%) has been observed in patients with MG infection. The influence of MG resistance to AMDs mutations on the frequency of clinical manifestations has not been established at low bacterial load of the pathogen (103—104 gEq/mL); the disease was asymptomatic in the majority (96%) of patients. Clinically apparent manifestations of the disease have been observed more often (p<0.05) in the patients with mutant strains of MG to AMDs compared to the individuals without mutation at high MG bacterial load (105—106 gEq/mL). Conclusion. The influence of MG resistance to AMDs mutations on the disease course emphasizes the need to integrate the genotypic identification of MG resistance into routine diagnostic laboratory process and STDs screening programs.