The perianal mycotic flora was studied in proctological patients with and without pruritus ani, as well as in control subjects. Four groups of patients underwent perianal mycoculture. In Group 1, 53 patients with anal pruritus were treated for benign anorectal disease. In Group 2, 24 patients with no underlying disease presented with anal pruritus. Both of these groups underwent concomitant chemical and parasitical examination of the faeces and an oral glucose tolerance test. In Group 3, 50 patients without pruritus ani at present or in the past were treated for benign anorectal diseases. In Group 4, 47 surgical patients without pruritus ani were treated for benign (9) and malignant (38) non-proctological diseases. In Group 1 the mycoculture was positive in 24/53 patients (Candida albicans 14, dermatophytes 10). In Group 2 fungal infections were seen in 16/24 patients (C. albicans 7, dermatophytes 9). No parasites or diabetes were found in either group. In Group 3 C. albicans was isolated in 14/50 patients. In Group 4 C. albicans was found in 11/47 cases (2 in benign, 9 in malignant diseases). Infection by C. albicans was observed in all groups studied, independent of the presence of disease or anal pruritus. The presence of dermatophytes was always associated with pruritus ani.