Abetalipoproteinemia is a rare disorder presenting in infancy or early childhood and affecting less than 1 in 1 million. It is characterized by the malabsorption of fats and lipid soluble vitamins resulting in hypocholesterolemia and vitamin deficiency. This is mainly caused by the improper packaging and secretion of apolipoprotein B-containing proteins. The disease can result in a failure to thrive, steatorrhia, developmental delay, spastic ataxia, neuropathy, retinal degeneration and hepatic steatosis.
The disease is diagnosed based on serum levels of lipids and fat soluble vitamins, absence of chylomicrons and VLDL in the plasma, acanthocytosis in blood films and presence of steatorrhic stools. Genetic testing to uncover a mutation in the MTP gene can confirm the diagnosis of abetalipoproteinemia. Treatment involves dietary therapy with reduced fat intake along with supplementation of medium chain triglycerides (MCT) and high doses of fat soluble vitamins.