Relationship between macrolide resistance mutations in Mycoplasma pneumoniae and its genotype

Abstract

Objective To analyze the relationship between macrolide resistance mutations in Mycoplasma pneumoniae (Mp) and its genotype by multiple-locus variable-number tandem-repeat analysis (MLVA). Methods One hundred and forty-three Mp-positive specimens were collected in Beijing (54 collected at the Affiliated Children′s Hospital of the Capital Institute of Pediatrics), the United States (59 collected at four different geographical locations: Kansas City, Missouri; Seattle, Washington; New York, New York; Chicago, Illinois) and Australia (30 provided by the diagnostic laboratory at the Centre for Infectious Diseases and Microbiology Laboratory Services, Institute of Clinical Pathology and Medical Research, Westmead Hospital, Sydney). Nested PCR was used to detect mutations in 23S rRNA. A capillary electrophoresis-based single tube multiplex PCR (mPCR-CE) was used to analyze the MLVA types of Mp in those samples. Results A2063G mutation was identified in 57 specimens including 49 from Beijing, seven from the United States and one from Australia. The 143 Mp-positive specimens were typed into 10 distinct MLVA types. Fifty-four specimens collected in Beijing belonged to four MLVA types, which were M4-5-7-2 (44/54, 81.5%), M3-5-6-2 (7/54, 13.0%), M4-5-6-2 (2/54, 3.70%) and M4-5-5-2 (1/54, 1.85%). Fifty-nine specimens collected in the United States belonged to six MLVA types including M4-5-7-2 (27/59, 45.8%), M3-5-6-2 (18/59, 30.5%), M3-6-6-2 (11/59, 18.6%), M3-5-6-1 (1/59, 1.69%), M4-5-7-3 (1/59, 1.69%) and M5-5-7-2 (1/59, 1.69%). Thirty specimens of Mp from Australia were grouped to five types with M3-5-6-2 (12/30, 40.0%) and M4-5-7-2 (10/30, 33.3%) and M3-5-7-2 (5/30, 16.7%) being the predominant types. Macrolide resistance mutations were detected in 57 out of 143 specimens (49 from Beijing, seven from the United States and one from Sydney) and 50 of them were MLVA type of M4-5-7-2. Conclusion The MLVA type of M4-5-7-2 is associated with macrolide resistance in Mp. Key words: Mycoplasma pneumoniae; Macrolide resistance; 23S rRNA; MLVA genotype