Infantile systemic hyalinosis: a fatal disorder commonly diagnosed among Arabs.

We retrospectively reviewed 19 patients (11 male, 8 female) with infantile systemic hyalinosis (ISH) seen at a tertiary care hospital. Fifteen patients (83.3%) presented in the neonatal period. The referral diagnosis was inaccurate in 14 patients (73.7%). Thirteen patients were products of first-degree cousin marriages (68%) and 5 families had more than one affected child. All patients had painful joint contractures and typical mucocutaneous changes (hyper-pigmented sclerodermatous skin over the knuckles and malleoli, gingival hyperplasia, subcutaneous and perianal fleshy nodules). Growth failure was noted in all of them and 39% had profuse diarrhea, 72% had low serum albumin. Radiological findings included osteopenia, periosteal reaction and osteolytic lesions. Tissue biopsy was consistent with the diagnosis in the 8 patients who had the biopsies. Despite aggressive management with physiotherapy and different medications (including NSAIDs, penicillamine and methotrexate), the disorder was progressive and none of them showed improvement. 16 patients died with a mean age of 11 months and only 3 are alive with a mean age of 20 months. This report represents the largest series of ISH. Our data suggests that ISH is a commonly diagnosed disorder in Saudi Arabia and among Arabs.