title: Clonal Spread of a Unique Strain of Macrolide-Resistant Mycoplasma Pneumoniae Within a Single Family in Italy.
abstract: Macrolide-resistant Mycoplasma pneumoniae (MR-MP) is an increasing problem worldwide. This study describes the clonal spread of a unique strain of MR-MP within a single family. On January 23, 2015, nasopharyngeal swabs and sputum samples were collected from the index case (a 9-year-old girl) in southern Italy. The patient had pneumonia and was initially treated with clarithromycin. MR-MP infection was suspected due to prolonged symptoms despite appropriate antibiotic therapy. Two further cases of pneumonia occurred in relatives (a 7-year-old cousin and the 36-year-old mother of the index case); therefore, respiratory samples were also collected from other family members. Sequence analysis identified mutations associated with resistance to macrolides. Both P1 major adhesion protein typing and multiple loci variable-number tandem repeat analysis (MLVA) typing were performed to assess the relatedness of the strains. The index case, the cousin, the mother, and another 4 family members (twin siblings of the index case, a 3-year-old cousin, and the grandmother) were positive for MR-MP. All strains harbored the mutation A2063G, had the same P1 subtype (1), and were MLVA (7/4/5/7/2) type Z. In addition, the index case's aunt (31 years of age and the probable source of infection) harbored an M pneumoniae strain with the same molecular profile; however, this strain was susceptible to macrolides. This cluster of MR-MP infection/carriage caused by a clonal strain suggests a high transmission rate within this family and highlights the need for increased awareness among clinicians regarding the circulation of MR-MP. Novel strategies for the treatment and prevention of M pneumoniae infections are required.
authors.affiliation: From the Department of Biomedical Sciences and Human Oncology-Hygiene Section (MC, DL, ALDR, AM, MQ, ST, CG), University of Bari; and Paediatric Unit of the Maternal and Child Health Department of "San Giacomo" Hospital of Monopoli (ES, MM), Bari, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Chironna
authors.forename: Daniela
authors.initials: D
authors.lastname: Loconsole
authors.forename: Anna Lisa
authors.initials: AL
authors.lastname: De Robertis
authors.forename: Anna
authors.initials: A
authors.lastname: Morea
authors.forename: Egidio
authors.initials: E
authors.lastname: Scalini
authors.forename: Michele
authors.initials: M
authors.lastname: Quarto
authors.forename: Silvio
authors.initials: S
authors.lastname: Tafuri
authors.forename: Cinzia
authors.initials: C
authors.lastname: Germinario
authors.forename: Mariano
authors.initials: M
authors.lastname: Manzionna
mesh_terms: D018829:Adhesins, Bacterial / Q000235:genetics*; D000328:Adult; D015373:Bacterial Typing Techniques; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005190:Family; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D018942:Macrolides; D008297:Male; D058885:Multilocus Sequence Typing; D009154:Mutation; D009177:Mycoplasma pneumoniae / Q000145:classification / Q000235:genetics*; D009305:Nasopharynx / Q000382:microbiology; D011019:Pneumonia, Mycoplasma / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D020080:Tandem Repeat Sequences
chemical_list: D018829:Adhesins, Bacterial; D018942:Macrolides; C035471:adhesin, Mycoplasma pneumoniae