title: Identification of P1 types and variants of Mycoplasma pneumoniae during an epidemic in Chile.
abstract: This study was conducted to determine the types of M. pneumoniae prevalent in adults presenting with community-acquired pneumonia during an epidemic period, and to scrutinize a variable region of the RepMP4 element for the detection of P1 variants. All 23 clinical specimens PCR-positive for M. pneumoniae obtained in two hospitals in Santiago, Chile, from 2005 to 2006 were typed by a multiplex PCR directly and then the RepMP4 fragment of 18 specimens was sequenced. A predominance of M. pneumoniae type 2 was found, 18 (78.3 %) specimens being grouped as type 2 and 5 (21.7 %) as type 1. Co-infection of M. pneumoniae with other respiratory pathogens was found in 10/23 (43.4 %) patients, but their frequency was not related to the M. pneumoniae type. Sequence analysis revealed a single nucleotide polymorphism, a transition mutation, in 50 % of amplicons belonging to type 1 and in 71.4 % of amplicons of type 2. The nucleotide changes were synonymous in each P1 variant. In conclusion, during the 2005-2006 epidemic in Santiago, both types of M. pneumoniae circulated. Although the analysed area in the RepMP4 was small, we detected the existence of P1 variants in the two types of this organism.
authors.affiliation: Programa de Microbiología, Facultad de Medicina, Universidad de Chile, Santiago de Chile, Chile.
authors.forename: María A
authors.initials: MA
authors.lastname: Martínez
authors.affiliation: Hospital Clínico Universidad de Chile, Santiago de Chile, Chile.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Ruiz
authors.affiliation: Hospital de Infecciosos Dr Lucio Córdova, Santiago de Chile, Chile.
authors.forename: Enna
authors.initials: E
authors.lastname: Zunino
authors.affiliation: Programa de Virología, Facultad de Medicina, Universidad de Chile, Santiago de Chile, Chile.
authors.forename: Vivian
authors.initials: V
authors.lastname: Luchsinger
authors.affiliation: Centro de Síntesis y Análisis de Biomoléculas, Facultad de Medicina, Universidad de Chile, Santiago de Chile, Chile.
authors.forename: Raúl
authors.initials: R
authors.lastname: Aguirre
authors.affiliation: Programa de Virología, Facultad de Medicina, Universidad de Chile, Santiago de Chile, Chile.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Avendaño
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques; D002677:Chile / Q000453:epidemiology; D016000:Cluster Analysis; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology*; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D004196:Disease Outbreaks; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D009177:Mycoplasma pneumoniae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D010802:Phylogeny; D011019:Pneumonia, Mycoplasma / Q000453:epidemiology* / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D055815:Young Adult
chemical_list: D004269:DNA, Bacterial