Pachyonychia Congenita Jadassohn

Under the caption "Congenital Dyskeratosis," Erich Schäfer1 described a syndrome based on observations gathered from one case of his own and from thirteen others reported in the literature. The condition is characterized by: pachyonychia; acneform, follicular keratosis, especially about the knees and elbows; symmetrical and circumscribed plantar and palmar keratosis; hyperhidrosis of the palms and soles; leukoplakia of the oral mucosa, and anomalies of the hair. All the fourteen cases showed pachyonychial changes as a constant finding, while the remaining clinical features were variants. In Schäfer's case a boy, 12 years old, had had the characteristic ungual manifestations from birth. Brettauer's report2dealt with a boy 9 years old. The finger-nails were thickened, opaque, lusterless, partially loosened and in places swollen and lap-rolled in the longitudinal axis of the finger. According to Heller,1eJadassohn and Lewandowsky's case3of pachyonychia congenita belongs in this group. Siemens4likewise