[Infectious external otitis: etiology in the Terrassa region, culture methods, and considerations on otomycosis].

The etiology of infections of the outer ear was studied in the area of Terrassa (Barcelona) over a six-year period (1987-1992). A total of 1419 samples of ear discharge were processed. Traditional culture media were used to isolate the microorganisms as well as a modified culture medium prepared by us (APA). Usual methods were used to identify the microorganisms. The results show Pseudomonas aeruginosa to be the most frequently isolated microorganism. 76.5% of the otitis studied were unimicrobial and the presence of moulds or yeast was noted in 6.9% of samples. Otomycosis (5.9%) is one of the major pathological processes of the outer ear, and Aspergillus niger is the prime causal agent.