Juvenile hemochromatosis, also known as hemochromatosis type 2, is a rare form of hereditary hemochromatosis, which emerges in young individuals, typically between 15 and 30 years of age, but occasionally later. It is characterized by an inability to control how much iron is absorbed by the body, in turn leading to iron overload, where excess iron accumulates in many areas of the body and causes damage to the places it accumulates.It is a genetic disorder that can be caused by mutations in either the HJV (also called HFE2) or HAMP genes, and is inherited in an autosomal recessive fashion. Depending on which of these genes is affected, the disease can be further subdivided into types 2A and 2B. Signs and Symptoms
The most common symptoms of juvenile hemochromatosis are as follows:
Weakness
Lethargy
Hyperpigmentation (darkening of the skin)
Arthropathy (joint disease)
Diabetes
Heart disease (dilated cardiomyopathy). Complications of heart disease are the main cause of death in those with untreated hemochromatosis. Hypogonadism (reduced activity of the genitals), which may result in decreased libido and infertility
Amenorrhea in females
Erectile dysfunction in males
Loss of appetite
Increased risk of infection by certain bacteria including V. vulnificus.Other common complications include:

Congenital hepatic fibrosisLess common symptoms and complications include:

Osteoporosis
Hepatomegaly (liver enlargement)
Liver cirrhosis
Cardiac arrhythmias
Hypothyroidism
Adrenocortical insufficiency

Genetics
Juvenile hemochromatosis can be caused by inheriting two mutated copies (alleles), one from each parent, of the genes for the proteins hemojuvelin (HFE2/HJV) or hepcidin (HAMP), and the disease can be subdivided into hemochromatosis types 2A and 2B according to which gene/protein is affected.
Heart failure may require followup with cardiology specialist, as well as medical treatment with certain medications including ACE inhibitors and diuretics. Hypogonadism may require treatment with hormone replacement therapy, which has also been shown to reduce the likelihood of developing osteoporosis later on. Liver cirrhosis may require beta blockers, a kind of antihypertensive medication. Joint pain, called arthralgias, can be treated with NSAIDs, a type of pain medication available over-the-counter. Epidemiology
The incidence of juvenile hemochromatosis in the general population remains unknown at this time, however it is very rare. It more commonly occurs in those of European descent, becoming apparent during the first to third decades of life, and affects males and females at similar rates. References
External links
GeneReview/NIH/UW entry on Juvenile Hereditary Hemochromatosis