Keratosis punctata and atopy. Report of 31 cases with a prospective study of prevalence

We report 31 cases of keratosis punctata palmaris et plantaris in blacks. Eleven of these were found in a prospective study of 573 consecutive black private dermatologic outpatients, a prevalence of 1.9%, and 20 cases were randomly encountered over a three-year period in the same office. Five of the 30 patients able to give a history were symptomatic, and they and ten others came to the office because of this disease, where as 15 came for other reasons, two of whom were unaware of the disease. Four of the 31 patients also had foot lesions. Four patients were aware of relatives with palmar keratoses. The mean duration of disease was 4.3 years, the median was three years, and the range was zero to 38 years. The mean age at onset was 30.3 years, the median was 29 years, and the range was 12 to 70 years, with one case beginning in infancy. Each patient in the prospective study was examined for personal atopy or for a family history of atopy. Nine (82%) of the 11 patients with keratosis punctata had atopy and/or a family history of atopy. Statistical analysis confirmed the association between keratosis punctata and atopy in the prospective study.