Microbiology of perianal cellulitis in children: comparison of skin swabs and needle aspiration

Objective To establish the aerobic and anaerobic microbiology of perianal cellulitis in children, comparing skin swab and needle aspirate methodology. Method Swabs of involved skin and needle aspirates of cellulitis were studied for aerobic and anaerobic bacteria. Results Specimens obtained from 10 patients with perianal cellulitis showed bacterial growth. Polymicrobial aerobic–anaerobic flora was found in all skin surface cultures, where the predominate isolates were Peptostreptococcus spp., Escherichia coli , and alpha hemolytic streptococci. The number of isolates in needle aspirates varied between one and two. The predominant ones were E.coli (3), Peptostreptococcus spp. (3), Staphylococcus aureus (2), and Bacteroides fragilis group (2). Complete or partial concordance in microbiology between skin swabs and needle aspirates was present in six instances. In four instances, isolates recovered from needle aspirates were not isolated from the skin surface. Conclusions This study demonstrates the diversity of aerobic and anaerobic organisms isolated from perianal cellulitis, and the superiority of needle aspirates in establishing the microbiology of the infection.