Pachyonychia congenita: A rare genodermatosis

Pachyonychia congenita (PC) is a rare genodermatosis with only 450 cases reported since 1906. It is of two types, type I due to mutation in genes 6a and 16, and 6b and 17 in type II with an autosomal dominant inheritance in both types. A 22 yr old female patient presented in our OPD with hypertrophy of finger and toe nails, palmoplantar keratoderma, oral punctuate leukokeratosis, hyperhidrosis in palms and soles with maceration and malodour since childhood. She had a positive family history with father and grandfather affected but less severely. Microscopy and culture of nail clippings and scrapping were done to rule out fungal infection. On biopsy acanthotic epidermis, parakeratosis, orthokeratosis were seen. No evidence of any associated malignancy was found after thorough workup. She was diagnosed as PC Type 1. She was put on topical steroids and orally on acetretin 25 mg OD. Paring of the nails was done too reduce the thickness of nails & to provide symptomatic relief. She was on a regular treatment for 3-4 months and showed some improvement in the form of reduced palmoplantar hyperkeratosis and reduced oral punctate keratosis but was later lost on followup. She showed no adverse effect to therapy during this period. This case is being reported because of its rarity.