title: Prevalence of Panton-Valentine leucocidin and phenotypic and genotypic characterization of biofilm formation among Staphylococcus aureus strains isolated from children with adenoid hypertrophy.
abstract: Adenoids as a first line of host defense against respiratory microbes play an important role in majority of upper airway infectious and noninfectious illnesses. Bacterial pathogen can colonize on the adenoid tissue and probably act as a reservoir for them. To determine phenotypic and genotypic characterization of biofilm forming capacity of Staphylococcus aureus isolates from children with adenoid hypertrophy and prevalence of Panton-Valentine leukocidin (PVL) gene we collected 17 consecutive, clinically significant S. aureus isolates from children with adenoid hypertrophy undergoing adenoidectomy with one or more of the upper airway obstruction symptoms, nasal obstruction, mouth breathing, snoring, or sleep apnea. Biofilm formation was evaluated by colorimetric microtiter plate's assay. Gene encoding PVL and adhesion- or biofilm formation-encoding genes were targeted by polymerase chain reaction (PCR) assay. According to the results, all strains produced biofilm. Seven (41.2%) isolates produced strong biofilm whereas 7 (41.2%) isolates produced week and 3 (17.6%) isolates produced medium biofilm. Regarding the adhesion- or biofilm formation-encoding genes, 16 (94.1%) isolates were positive for the gene eno, 13(76.4%) for icaA, 13 (76.4%) for icaD, 10 (58.8%) for fib, 10 (58.8%) for fnbB, 4(23.5%) for can, and 1(5.8%) for fnbA. The high prevalence of genes encoding biofilms and adhesins and phenotypic ability to form a biofilm by S. aureus strains emphasizes the pathogenic character of strains isolated from children with adenoid hypertrophy.
authors.affiliation: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Emaneini
authors.affiliation: Department of Microbiology and Clinical Microbiology Research Center, Faculty of Medicine, Yasuj University of Medical Sciences, Yasuj, Iran.
authors.forename: Seyed Sajjad
authors.initials: SS
authors.lastname: Khoramrooz
authors.affiliation: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shadi
authors.initials: S
authors.lastname: Shahsavan
authors.affiliation: Department of Medical Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Dabiri
authors.affiliation: Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: jabalamf@tums.ac.ir.
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Jabalameli
mesh_terms: D000234:Adenoids / Q000382:microbiology*; D018829:Adhesins, Bacterial / Q000032:analysis / Q000235:genetics; D001427:Bacterial Toxins / Q000032:analysis* / Q000235:genetics; D018441:Biofilms / Q000254:growth & development*; D002648:Child; D005098:Exotoxins / Q000032:analysis* / Q000235:genetics; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D006984:Hypertrophy / Q000382:microbiology*; D007956:Leukocidins / Q000032:analysis* / Q000235:genetics; D010641:Phenotype; D016133:Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology
chemical_list: D018829:Adhesins, Bacterial; D001427:Bacterial Toxins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin
keywords: Adenoid hypertrophy; Biofilm; PVL; Staphylococcus aureus