Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae among children with acute otitis media in Marrakech, Morocco

Sara Amari; Karima Warda; Youssef Elkamouni; Lamiae Arsalane; Mohamed Bouskraoui; Said Zouhair

doi:10.18502/ijm.v14i1.8801

Sara Amari Department of Medical Biology, Laboratory of Microbiology and Virology, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakesh, Morocco
Karima Warda Department of Medical Biology, Laboratory of Microbiology and Virology, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakesh, Morocco
Youssef Elkamouni Department of Medical Biology, Laboratory of Microbiology and Virology, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakesh, Morocco
Lamiae Arsalane Department of Medical Biology, Laboratory of Microbiology and Virology, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakesh, Morocco
Mohamed Bouskraoui Department of Pediatrics, Mohammed VI University Hospital, Marrakesh, Morocco
Said Zouhair Department of Medical Biology, Laboratory of Microbiology and Virology, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakesh, Morocco

DOI: https://doi.org/10.18502/ijm.v14i1.8801

Keywords: Otitis media; Preschool children; Colonization; Streptococcus pneumoniae; 10 valent pneumococcal vaccine; Serotyping; Antibacterial drug resistance

Abstract

Background and Objectives: Streptococcus pneumonia (S. pneumoniae) is one of the most frequent pathogens leading to a variety of clinical manifestations. The effects of S. pneumoniae carriage on acute otitis media (AOM) are poorly studied. The study aimed to assess the serotype’s distribution and antimicrobial susceptibility in children with AOM after the implemen- tation of the pneumococcal conjugate vaccine (PCV) in Morocco.

Materials and Methods: We conducted a prospective study of AOM children aged 6 to 36 months who visited pediatric centers in Marrakesh between January to June 2018. Parents were asked to complete a questionnaire and a swab was col- lected from each child. The S. pneumoniae strains were further identified (Hemolysis, optochin sensitivity, and agglutination test), serogrouped (IMMULEX PNEUMOTEST agglutination test), serotyped (Real time PCR) and tested for antimicrobial susceptibility.

Results: The S. pneumoniae carriage rate was 49.7% (87/175). As estimated, non-vaccine serotypes (NVT) were most prev- alent (51/63; 81%). The most frequent serotypes were 6C/6D (12.7%), 10 (9.5%), and 19B/19C (9.5%). The S. pneumoniae strains that were isolated showed a diminished susceptibility to penicillin G with a rate of 27.5%. Penicillin non-susceptible pneumococci (PNSP) was mostly associated with NVT. More than 90% of S. pneumoniae isolates were susceptible to chlor- amphenicol (97.5%), clindamycin (97.5%), erythromycin (97.5%), levofloxacin (97.5%), pristinamycin (97.5%), gentamicin (92.5%), and teicoplanin (92.5%).

Conclusion: Important nasopharyngeal carriage prevalence was reported among children with AOM. The study showed that new NVT are emerging, including 6C/6D and 10. Furthermore, susceptibility was significantly higher against all antibiotics tested except for penicillin G and amoxicillin.