Isolation and Identification of Mycelial Fungi Associated with Human Ear Infections

Abstract

The aim of this study was to isolate and identify the mycelial fungi (mold) associated with human ear infections. A total of 100 ear swabs were collected from patients attending Ear, Nose and Throat (ENT) Hospital, Khartoum, during the period from June to September, 2006. Samples were taken from patients irrespective to age or sex. The samples were subjected to conventional mycological examination after being cultured on Sabouraud's Dextrose Agar and Corn Meal Agar. The mycological examination work was executed at the Department of Microbiology, Faculty of Veterinary Medicine, University of Khartoum. Out of the 100 samples collected, 47(47%) were positive for mycelial growth, while 53 (53%) werenegative. After the purification process, the total number of isolates was 47 (no specimen gave more than one type of mycelial growth). Based on their microscopic and cultural characteristics, the isolates were identified as: Aspergillus niger(n=28, 59.6%) as the most dominant suspected pathogen, followed by A. flavus (n=10, 21.3%), A. terreus(n=6, 12.8%), Penicilliumspecies (n=1, 2.1%), Curvulariaspecies (n=1, 2.1%) and Scopulariopsis species (n=1, 2.1%). The Aspergillusspecies constituted 93.6% of the total isolates and their isolation frequency from the total samples as 44%. XIII It was observed that 84% ofpatients visiting the ENT Hospital were 30 years old or less; and the rate of fungal ear infection is inversely proportional with age of patients. Likely, 38 (80.8%) isolates were obtained from ages of 30 years or less; of which 34% were from ages of 10 years or less. Isolation frequency of mycelial fungi was almost similar in both sexes; however, in young ages(up to 30 years), the rate of isolation was higher in males than in females and viseversa in older patients.