Hereditary ovalocytosis is rare condition passed down through families (inherited) in which blood cells are slightly oval-shaped instead of round. It is a form of hereditary elliptocytosis.

Ovalocytosis is mainly found in Southeast Asian populations.

Newborn infants with ovalocytosis may have anemia and jaundice. Adults usually do not show symptoms and are known as asymptomatic.

An examination by your health care provider may occasionally show an enlarged spleen.

This condition is diagnosed by looking at the shape of blood cells under a microscope. The following tests may also be done:

• Complete blood count (CBC) to check for anemia or red blood cell destruction
• Blood smear to determine cell shape
• Bilirubin level (may be high)
• LDL "bad" cholesterol level (may be high)
• Ultrasound of the abdomen (may show gallstones)

In severe cases, the disease may be treated by removal of the spleen (splenectomy).

The condition may be associated with gallstones or kidney problems.

Jeng MR. Hematologic problems in immigrants from Southeast Asia. Hematol Oncol Clin North Am. Dec 2004;18(6):1405-22, x.

Laosombat V, Dissaneevate S, Wongchanchailert M, Satayasevanaa B. Neonatal anemia associated with Southeast Asian ovalocytosis. Int J Hematol. 2005 Oct;82(3):201-5.