Abstract
Four cases of benign acanthosis nigricans in one family were reported. Ten cases in three generations of the predigree of this family had this disease. Case 1: A 36-year-old woman was the mother of case 2, 3 and 4, and noted dark brownish pigmentation, papillomatous growth and prominence of lichenification on the neck, axillae, side of the brest, loin and umbilical region in her childhood. The lesions became darker in color at puberty, especially during the period of pregnancy, and lately had a tendency to slight discoloration. She had no internal malignant tumors and obesity, and her chromosomes were normal. Our laboratory studies did not reveal any remarkable results, except that slight retardation of pituitary-adrenal function was proved by metopirone test and ACTH-Z test. Histologic specimen showed hyperkeratosis, papillomatosis and melanization in the basal cell layer. Case 2, 3, 4: A 13-year-old boy, a 6-year-old girl, and a 2-year-old boy, members of the same family of case 1, were normal at birth, and showed clinical features of this disease since one year of age. The older were they, the severer were the lesions. It seemed that case 1 and 2 might be complete type of case 3 and 4. Their chromosomes were normal. Case 2 showed mental deficiency (I.Q.=66).
