Polymorphisms involving the Pneumocystis jirovecii-related genes in AIDS patients in eastern China

Objective: To investigate the genetic polymorphisms of mitochondrial large ribosomal subunit (mtLSU)-rRNA, dihydrofolate reductase (DHFR), dihydropteroate synthase (DHPS), cytochrome b (CYB), and superoxide dismutase (SOD) genes and its correlation with clinical outcomes of Pneumocystis jirovecii pneumonia in acquired immune deficiency(AIDS) patients. Methods: Eighty AIDS patients with P. jirovecii pneumonia that were admitted to our hospital from 2016 to 2018 were included in this study. Their demographic information and clinical data were collected, as well as corresponding saliva specimens for PCR and sequencing of mtLSU-rRNA, DHFR, DHPS, CYB, and SOD genes to analyze genetic polymorphisms, different polymorphic combinations, and clinical outcomes. Results: Of the 80 saliva specimens, mtLSU-rRNA was successfully amplified and sequenced in 30 cases; CYB was successfully amplified and sequenced in 26 cases; and SOD, DHFR, and DHPS were successfully amplified and sequenced in 18 cases. These results indicate that The mtLSU-rRNA, CYB, and SOD genes were highly polymorphic. mt85T and CYB1 were the variants dominantly detected at the mtLSU-rRNA and CYB loci, respectively. The SOD1 and SOD2 variants (each in 50% of the cases) were detected at the SOD locus. Among the 18 cases that were successfully amplified and sequenced for DHFR and DHPS, three DHFR nonsense mutations and no DHPS mutation were observed. The mt85C, CYB1, SOD1, and DHFR312T genes harbored common polymorphisms (n = 4; 22.22%) and the mt85T, CYB1, SOD1, DHFR312T genes were associated with poor clinical outcomes. Conclusion: The types of genetic polymorphisms and polymorphic combinations of mtLSU-rRNA, DHFR, DHPS, CYB, and SOD in P. jirovecii were related to the clinical outcomes of patients with P. jirovecii pneumonia in Zhejiang Province, China.