Microbiology of Chronic Otitis Media

Middle ear swabbed samples from patients (aged ≤1 yr to ≥ 60 yrs) attending Ear, Nose and Throat (ENT) clinics at Uyo and Ikot Ekpene with chronic otitis media (COM) were analyzed microbiologically. The occurrences of DNase, β-lactamase, haemolysin production and susceptibility of the isolates obtained to antibiotics were determined using standard techniques. Staphylococcus aureus 65 (24.7%), Pseudomonas aeruginosa 53 (20.1%). Proteus mirabilis 22 (8.4%), Streptococcus pneumoniae 21 (7.9%), coagulase negative Staphylococcus spp 19 (7.2%), Klebsiella pneumoniae 18(6.8%), Escherichia coli 17 (6.5%), Proteus vulgaris 10 (3.8%), Serratia marcescens 9 (3.4%), Streptococcus pyogenes 10 (3.8%), Enterobacter spp 8 (3.0%), Morgenella morganii 7 (2.7%), and Bacillus substilis 4 (1.5%) were obtained. Fungal isolated were 29.2% Aspergillus niger, 6.3% Aspergillus flavus, 22.9% were Candida albicans, 10.4% Candida spp, 17.7% Cryptococcus neoformans and 13.5% Fusarium spp. S. aureus and B. substilis had the highest and lowest frequency of occurrences in both sexes, respectively. Of 31 isolates that showed positivity for β haemolysis, 7 (70.0%) were S. pyogenes and 15 (23.1%) from S. aureus. S. aureus was the highest DNase producers, followed by S. pyogenes 4 (40.0%) and CoN Staphylococcus spp. 1 (5.3%). β-lactamase detection ranged from 28.6% in M. morganii to 55.6% in S. marcescens. Haemolysin and DNase producing C. albicans and other Candida spp were isolated. Between 55.9% and 60.8% isolates were sensitive to ceftriaxone, cefotaxime and ceftazidime, while between 44.4% to 62.5% of Enterobacter spp and S marcescens were resistant to penicillin and ceftazidime. Of the 243 MDR bacteria, 136 (56.0%) were resistant to 4-8 antibiotics with indices ranging from 0.17 to 0.67. C. albicans and A. niger were more sensitive to nystatin than other fungal spp, while between 30.2% to 39.6% of the fungi were resistant to fluconazole and ketoconazole. Conclusively, this study showed the need to find compounds that potentiate antimicrobial activity against multidrug resistant organisms especially those associated with chronic otitis media.