Bacteriology of chronic discharging ears in Port Harcourt, Nigeria

The objective of the study was to isolate and identify aerobic bacteria in chronic discharging ears and determine their antibiotic susceptibilities, which is essential for reasonable empiric treatment.

Ear swabs of discharging ears aseptically collected from 102 patients of various age groups attending Ear, Nose, and Throat out-patient clinic at University of Port Harcourt Teaching Hospital were cultured for bacterial agents using blood agar, chocolate agar and MacConkey agar. Culture plates were incubated aerobically at 37 degrees C for 24-48 hours. Isolates were identified using standard microbiological methods. Members of the family enterobacteriaceae were identified using enterotubes. Antibiotic susceptibility test was carried out for 13 drugs using disc diffusion method.

Seventy-eight percent of the patients studied were in the age group 0-14 years and there were more male infants than females. Gram negative bacteria comprised 75% of the isolates. Predominant isolates were Pseudomonas aeruginosa (41%), Proteus sp. (22%), Staphylococcus aureus (22%), Escherichia coli and other coliforms (11%). Drug susceptibility profile of the isolates showed that ceftazidime, ceftriazone and gentamycin were most effective drugs in vitro.

The predominant bacterial agents in chronic discharging ears in Port Harcourt, Nigeria were gram negative bacteria and included Pseudomonas aeruginosa, Proteus sp., Escherichia coli. Gram positive bacterial constituted 25 percent of the isolates and included Staphylococcus aureus, Staphylococcus epidermidis and streptococcus sp. Ceftazidime, ceftrixone and gentamycin were the most effective drugs in vitro.