Uncommon microbial etiologies and their antimicrobial susceptibility profiles in pediatric community-acquired pneumonia

Background Community-acquired pneumonia (CAP) is a leading cause of childhood morbidity. The microbial etiology of CAP is paramount for guiding effective antibiotic therapy. Aim The study aimed to identify the spectrum of microorganisms isolated from children admitted with CAP, and to demonstrate their antimicrobial susceptibility profiles. Patients and methods A cross-sectional study was conducted on 68 children (1 month to 13 years), who were admitted to the Alexandria University Children’s Hospital with the diagnosis of CAP. Children with immunodeficiency, chronic lung diseases, chronic medical conditions predisposing to pneumonia, hospital-acquired pneumonia, or admitted to PICU were excluded. Blood cultures and nasopharyngeal aspirate cultures were obtained from every child. Microbial identification and antimicrobial susceptibility were performed. Results We obtained 136 cultures from 68 children. Forty-seven cultures tested positive (47/136, 34.6%), comprising 34 from nasopharyngeal aspirate culture (34/136, 25%) and 13 from blood cultures (13/136, 9.56%). Staphylococcus aureus was the most common isolate (14/47, 29.8%) with a universal susceptibility to both linezolid and vancomycin. It was followed by Candida albicans and Klebsiella pneumoniae (11/47, 23.4% each) and Pseudomonas aeruginosa (8/47, 17.0%). Acinetobacter baumannii, Escherichia coli , and Streptococcus pneumoniae were isolated from 1 (2.1%) culture each. All isolated gram-negative organisms were fully sensitive to colistin, followed by aminoglycosides and quinolones. For Candida isolates, Amphotericin B and miconazole were the most effective antifungal agents. Conclusion In pediatric CAP, uncommon organisms have been isolated from microbial cultures. S. aureus, K. pneumoniae, C. albicans , and P. aeruginosa were the most common organisms. Antimicrobial resistance was encountered against most of the first-line antimicrobials. This microbial profile and antimicrobial susceptibility call for urgent national and local interventions against antimicrobial resistance.