Juvenile hemochromatosis.

Juvenile hemochromatosis or type 2 hemochromatosis is a rare inherited recessive disease, which leads to severe iron overload earlier in life than HFE-related hemochromatosis. Increased transferrin saturation and serum ferritin as well as parenchymal iron deposition and liver fibrosis may be observed in childhood. Clinical symptoms of hypogonadism and cardiac disease develop before the age of 30. The disease is usually progressive and if untreated may become fatal because of heart failure. The type 2 hemochromatosis locus maps to chromosome 1q21, but the gene has not yet been isolated. The severity and the early expression of juvenile hemochromatosis suggest that the gene product has a crucial role in the regulation of iron homeostasis. Copyright 2002, Elsevier Science (USA).