Summary
Haim-Munk syndrome (HMS) is characterized by palmoplantar hyperkeratosis, severe early-onset periodontitis, onychogryposis, pes planus, arachnodactyly and acroosteolysis. HMS is rare with less than 100 cases reported in the literature so far. The majority of reported cases are descendants of a few consanguineous families from a religious isolate in Cochin, India. One unrelated Brazilian patient has also been reported. HMS presents with severe and extensive skin manifestations. In addition to the marked palmoplantar keratosis, patients have scaly erythematous and circumscribed patches on the elbows, knees, forearms, shins and dorsum of the hands. Severe, early-onset progressive periodontitis that affects both the deciduous and permanent dentitions and presents with gingival inflammation and alveolar bone destruction is a hallmark of the disease. Onychogryposis, arachnodactyly, acroosteolysis and pes planus are additional features that help to distinguish HMS from other forms of palmoplantar hyperkeratosis. A peculiar deformity of the fingers (tapered, pointed phalangeal ends and a claw-like volar curve) is typical. Destructive arthritis of the wrist and shoulder joints has been reported in isolated cases. Patients with HMS have increased susceptibility to infections. HMS is caused by germline mutations in the lysosomal protease cathepsin C (CTSC) gene mapped to chromosome 11q14.1-q14.3. It is transmitted as an autosomal recessive trait. Mutations in the same gene cause the clinically related disorders Papillon-Lefèvre syndrome (PLS) and prepubertal periodontitis (see these terms). Diagnosis is clinical but can be confirmed by detection of the disease-causing mutation. Differential diagnosis includes the allelic disorder PLS and disorders with palmoplantar hyperkeratosis and prepubertal periodontitis. Management of the skin manifestations requires topical emollients, keratolytics (including salicylic acid and urea) and oral retinoids (acitretin, etretinate, and isotretinoin). Periodontitis in HMC is usually unresponsive to traditional periodontal therapies. Patients may benefit from extraction of the primary teeth combined with oral antibiotics and professional tooth cleaning. Synovectomy has been shown to alleviate the inflammation associated with destructive arthritis but may lead to loss in the range of the joint motion. *Author: Orphanet (November 2008)*.
