Overlapping Hyaline Fibromatosis Syndrome: A Rare Case of Juvenile Hyaline Fibromatosis and Infantile Systemic Hyalinosis.

Juvenile hyaline fibromatosis (JHF) and infantile systemic hyalinosis (ISF) are rare progressive, fatal autosomal recessive fibromatosis disorders that are characterized by the deposition of hyaline in various tissues. Mutations in capillary morphogenesis gene 2 are responsible for both of these conditions. These disorders usually present with fleshy, papular lesions, joint contractures, gingival hyperplasia, and persistent diarrhoea. An 18-month-old boy presented with multiple scalp abscesses, facial nodules, gingival hypertrophy, hypertrophic verrucous plaques and joint contractures with unique dermoscopic features and a history of recurrent diarrhoea and infections. Histopathological examination following skin biopsy revealed deposition of hyaline in the stroma and subcutaneous tissues. JHF is a differential diagnosis in children who present with multiple scalp nodules. Here, we report the case of overlapping features of JHF and ISH. The evolution of this case provides a special opportunity to further understand the pathogenesis and clinical characterization of hyaline fibromatosis syndrome.