High prevalence of Streptococcus pneumoniae in adenoids and nasopharynx in preschool children with recurrent upper respiratory tract infections in Poland – distribution of serotypes and drug resistance patterns

Abstract

BackgroundStreptococcus pneumoniae is one of the major bacterial pathogens colonizing nasopharynx, and often causes upper respiratory tract infections in children. We investigated the prevalence of S. pneumoniae in nasopharynx and adenoid core in 57 children aged 2–5 years who underwent adenoidectomy for recurrent pharyngotonsillitis, and we determined serotypes and antibiotic resistance patterns of the isolated pneumococci.Material/MethodsThe nasopharyngeal specimens obtained before adenoidectomy and the adenoids after the surgery were cultured for pneumococci. All isolates were serotyped by means of Quellung reaction. Susceptibility to antibiotics was determined according to EUCAST recommendations.ResultsS. pneumoniae colonization was observed in 40 (70.2%) children. From 29 (50.9%) children S. pneumoniae was isolated both from nasopharynx and adenoid core; 2 or 3 different isolates were identified in 8 (14.0%) children. In 8 (14.0%) children pneumococci were obtained from adenoid core only and in 3 (5.3%) children from nasopharynx only. Among the isolates, 35.3% were susceptible to all tested antimicrobials and 45.1% had decreased susceptibility to penicillin. Multidrug resistance was present in 52.9% of the isolates. The most frequent was serotype 19F (25.5%). The prevalence of serotypes included in pneumococcal conjugate vaccines PCV10 and PCV13 was 51.0% and 62.7%, respectively.ConclusionsThe adenoids, like the nasopharynx, can be regarded as a reservoir of pneumococci, including multidrug resistant strains, especially in children with indication for adenoidectomy due to recurrent respiratory tract infections refractory to antibiotic therapy. Good vaccine coverage among the isolated pneumococci confirmed the validity of the routine immunization by PCVs in young children.

Low Concentrations of Nitric Oxide Modulate Streptococcus pneumoniae Biofilm Metabolism and Antibiotic Tolerance

“…The error bars indicate standard deviations. bacterial recalcitrance (34,35). Thus, when combined with NO, antibiotic tolerance within the biofilm was significantly diminished.…”

“…We therefore tested whether NO treatment of pneumococcal biofilms could further reduce bacterial viability when used as an adjunctive treatment in conjunction with a conventional antibiotic used to treat otitis media. Serotype 2 strain D39 biofilms and biofilms from 3 different clinical isolates representative of serotypes 14 (ST124), 19F, and 23F, and based on their high isolation frequency in OM (20) and high rates of antibiotic recalcitrance, were used to assess NO adjunctive treatment (34,35). Established biofilms were treated with 1 mM SNP and 300 or 60 g/ml AMC for 2 h, and the viability of the remaining pneumococcal biofilm bacteria was assessed by CFU enumeration.…”

Resistant Streptococcus pneumoniae strains in children with acute otitis media– high risk of persistent colonization after treatment

“…Swabs and MEF samples were inoculated on selective Mueller-Hinton agar with 5% sheep blood and 5 mg/L of gentamicin for selective cultivation of streptococci. The identification and serotyping of S. pneumoniae , and susceptibility testing to selected antibiotics were performed in the same manner as in our previous researches [ 19 , 20 ].…”

The possibilities for the rational pharmacotherapy of adenoiditis in the children

“…По мнению одних исследователей, ве-дущим в развитии хронического воспаления в носоглотке считают Streptococcus pneumoniae [6,7]. Согласно другой точке зрения, главенствующими бактериальными патоге-нами являются представители грамотрицательной фло-ры -Haemophilus influenzae и Moraxella catarrhalis.…”