Bantu siderosis

Synonyms

African iron overload
African siderosis
Hereditary iron overload and African Americans
Iron overload in Africa

Overview

Bantu siderosis is an iron overload disorder initially observed in South African people. It involves absorption of too much iron from the diet.The excess iron is stored in the body's tissues and organs, particularly the liver, bone marrow, and spleen. Bantu siderosis results from a diet high in iron. It is particularly associated with consumption of a traditional African beer that contains dissolved iron from the metal drums in which it is brewed. Some evidence suggests that a genetic predisposition to absorbing too much iron may also be involved.

Symptoms

  • Iron deposits in liver
  • Liver cirrhosis
  • Impaired liver function
  • Enlarged liver
  • Iron deposits in spleen
  • Iron deposits in bone marrow

Causes

The exact cause of Bantu siderosis overload is unknown, but researchers believe that a combination of dietary and genetic factors result in the development of the disorder. High iron in the diet seems to be the major contributor to development of the condition. There also may be a genetic contribution, but the inheritance pattern is unknown. People with a specific variation in the SLC40A1 gene may inherit an increased risk of this condition, but not the condition itself. The SLC40A1 gene provides instructions for making a protein called ferroportin. This protein is involved in the process of iron absorption in the body.

Diagnosis

Diagnosis of Bantu siderosis involves a variety of blood tests to assess the total body iron. A liver biopsy detects the iron concentration in the liver and MRIs can measure the amount of iron accumulation through magnetism in the liver, heart, and pituitary gland.

Prognosis

In Bantu siderosis, the resulting iron overload can eventually damage tissues and organs. Iron overload in the liver may lead to chronic liver disease (cirrhosis). Cirrhosis increases the risk for developing a type of liver cancer called hepatocellular carcinoma. Iron overload in immune cells may affect their ability to fight infections. Bantu siderosis is associated with an increased risk of developing infections such as tuberculosis.

Treatment

The amount of hemoglobin is important when considering treatment options. If the patient has an ample blood supply, a physician can perform a phlebotomy (drawing blood). When the hemoglobin levels are too low, iron removal drugs can be used (iron-chelation).

Resources

  • NIH