This 40-year-old man was evaluated for thick scaly papules and plaques over his palms and soles with dystrophic nails since early childhood. He complained of hyperhidrosis of the palms and soles and frequent paronychia infections. He had no oral or ophthalmologic findings, dental abnormlities, or other skin findings. He was managed with acitretin 25 mg daily and paring of the plaques on the hands and feet weekly.
Pachonychia congenita is charfacterized by mutations in keratins 6 and 17. Four types have been described. Type I (Jadassohn-Lewandowsky Syndrome) shows hyperkeratotic nails with frequent paronychia, folicular hyperkeratosis of the elbows and knees, oral leukokeratosis and palmar plantar hyperkeratosis with hyperhidrosis. Type II (Jackson-Lawler Syndrome) additionally displays natal teeth and steatocystoma multiplex. Type III (Schafer-Braunauer Syndrome) also resembles type I with the addition of leukokeratosis of the corneas. Type IV (Pachonychia Congenita Tarda) is characterized by late onset, typically in the 2nd or 3rd decade.
thickened yellow nails particularly distally with subungual thickening