Molecular Characterizations of PCR-Positive Mycoplasma pneumoniae Specimens Collected from Australia and China

Abstract

bMycoplasma pneumoniae is an important cause of community-acquired pneumonia (CAP). In this study, M. pneumoniae strains in PCR-positive specimens collected from patients in Sydney, Australia (30 samples), and Beijing, China (83 samples), were characterized using multilocus variable-number tandem-repeat (VNTR) analysis (MLVA), P1-restriction fragment length polymorphism (RFLP) analysis, and sequencing of domain V of the 23S rRNA gene to compare genotype distribution and macrolide resistance rates between locations. Eighteen distinct MLVA types were identified in specimens from Sydney, of which 10 were known (types E, G, J, M, N, P, U, V, S, and X) and 8 previously unknown. Strains were equally distributed between P1-RFLP type 1 and type 2 variants. Among samples from Beijing, MLVA types E, G, J, P, U, X, and Z and four new types were identified. Most specimens belonged to P1-RFLP type 1. A nomenclature based on five VNTR loci is proposed to designate MLVA patterns. Macrolide resistance-associated mutations were identified in only 1 of 30 specimens (3.3%) from Sydney and 71 of 83 (85.5%) from Beijing (P < 0.05). This study demonstrated that although multiple individual M. pneumoniae strains were circulating in Beijing, the genotypes were less diverse than those in Sydney. However, the greatest regional difference was in the incidence of macrolide resistance, which may reflect differences in antibiotic use and/or measures in resistance control. Mycoplasma pneumoniae is an important pathogen causing community-acquired pneumonia (CAP), especially in children and young adults (1, 2). M. pneumoniae infections are increasingly recognized epidemically worldwide and as being endemic to some regions (3, 4). Previous reports showed regional differences in molecular profiles of M. pneumoniae (3, 5-7). Knowledge of these molecular characteristics is essential for outbreak investigation and to monitor the epidemiology of M. pneumoniae infections.For the past 20 years, P1 gene restriction fragment length polymorphism (P1-RFLP) has been the most common molecular typing method for M. pneumoniae (8)(9)(10). Recombination events at two repetitive sequence loci, RepMP2/3 and RepMP4, (11) in the P1 gene contribute to gene variation, as reflected in sequence variants and subtypes, but the discriminatory power of this method is limited (12)(13)(14). Recently, a multilocus variable-number tandemrepeat (VNTR) analysis (MLVA) method was developed by Dégrange et al. for M. pneumoniae isolates; this has a higher discriminatory power and can differentiate more than 26 distinct types (15). A culture-independent MLVA method for use directly from clinical specimens has also been described (7). Macrolideresistant M. pneumoniae clinical isolates were first reported in the 1990s, and the incidence has been increasing ever since, with various rates in different geographic regions (16)(17)(18)(19)(20).In this study, we used MLVA, P1-RFLP analysis, and detection of macrolide resistance-associated mutations to compare characteristics of M. pneumoniae...

Multiple-Locus Variable-Number Tandem-Repeat Analysis of <i>Mycoplasma pneumoniae</i> Isolates between 2004 and 2014 in Yamagata, Japan: Change in Molecular Characteristics during an 11-year Period

“…The proportions of MLVA and P1 types were reported to vary among geographic regions, as has the prevalence of macrolide resistance-associated mutations (9)(10)(11)20,21). We also reported P1 types and the prevalence of macrolide resistance-associated mutations of M. pneumoniae isolates in Yamagata, Japan between 2004 and 2013 (22).…”

Emergence of Macrolide-Resistant Mycoplasma pneumoniae in Hong Kong Is Linked to Increasing Macrolide Resistance in Multilocus Variable-Number Tandem-Repeat Analysis Type 4-5-7-2

“…When treatment is indicated, a macrolide is usually the drug of choice (1,2). However, macrolideresistant M. pneumoniae (MRMP) has become increasingly prevalent worldwide, and high rates of infection (Ͼ80%) have been found in certain parts of the world (3)(4)(5)(6). MRMP infections have been associated with persistence of symptoms, slower reduction in bacterial load, longer hospital stays, requirement of alternative therapy, and higher frequency of complications (1,7,8).…”

Comparison of Molecular Characteristics of Mycoplasma pneumoniae Specimens Collected from the United States and China

“…Previously, we reported the obvious differences in molecular characteristics of M. pneumoniae-positive specimens collected in Australia and China from 2008 to 2012 (9). To investigate further the molecular characteristics between different regions in this study, a comparison was conducted on specimens obtained from the United States and China.…”

“…Worldwide epidemics have been reported every 3 to 7 years, and they usually last up to 2 years each time (2,15). The latest global epidemic was from late 2010 to 2012 (2)(3)(4)(5)(6)(7)(8)(9). Decreasing herd immunity and different M. pneumoniae genotypes circulating in the human population are believed to be the main causes of epidemics (10).…”

“…Currently, P1 restriction fragment length polymorphisms (RFLP) and multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) are the most widely used methods for strain typing for this pathogen (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). We improved the MLVA method by amplifying four VNTRs (without Mpn1) in one tube for epidemic and outbreak analyses (11).…”