Onset in infancy or early childhood. Typical
diagnostic criteria are multiple hyaline subcutaneous fibroma, filamentous
tumors of the skin, gingival fibromatosis, muscle contractures of the
extremities, and multiple osteolytic bone destruction. Features include
osteolysis, diaphyseal anomaly, thickened gingivae, subcutaneous nodules,
and restricted joint mobility. Deposits have been described in larynx,
heart, and endocrine glands.