BACKGROUND The two feet-one hand syndrome is not uncommon; however, there have only been a few reports on this condition. This study was undertaken to obtain a better understanding of the epidemiology of the two feet-one hand syndrome. METHODS A retrospective chart review was conducted of all the patients seen in our practices over the past 15 years with the diagnosis of two feet-one hand syndrome. RESULTS A total of 80 patients with mycologically confirmed disease were identified (men, 72 (90%); women, 8 (10%); 77 (96%) Caucasian; 3 (4%) African-American; age (mean +/- standard error (SE)), 55.9 +/- 2.1 years). The mean age of the patients when the physician was first seen for the condition was 51.3 +/- 2.0 years. The mean ages when the symptoms first developed on the feet and hand were 37.1 +/- 2.4 years and 45.7 +/- 2.2 years, respectively. Tinea pedis was found to occur at an earlier age than tinea manuum (t(65) = 6.92, P < 0.01). There was a significant relationship between the hand in which tinea manuum developed, the hand used to excoriate the soles of feet (chi 2(4) = 14.82, P < 0.01), and the hand used to pick toenails (chi 2(4) = 14.82, P < 0.01); however, there was no significant relationship between handedness and the development of tinea manuum in the dominant hand. The occupation of the patient at the time of development of the two feet-one hand syndrome was categorized according to whether the intensity of hand use was high, moderate, or low. Patients with a high intensity of hand use in their jobs were significantly more likely to develop tinea pedis/onychomycosis (r = -0.27, F(1,61) = 4.77, P < 0.05) and tinea manuum (r = -0.30, F(1,62) = 6.31, P < 0.05) at an earlier age. The best multiple predictors of the age at which medical attention was sought were the age of onset of tinea manuum and a family history of tinea infection (r = 0.86, F(2,59) = 86.9, P < 0.01). The age of onset of tinea manuum was the best single predictor, with a correlation of 0.85. CONCLUSIONS In the two feet-one hand syndrome, the development of tinea pedis/onychomycosis generally preceded the development of tinea manuum. Tinea manuum usually developed in the hand used to excoriate the feet or pick toenails. Patients whose occupation involved a high intensity of use of the hands were more likely to develop the disease at an earlier age. Patients were more likely to seek attention once tinea manuum had developed, particularly if there was a family history of tinea infection.