Tangier disease (alpha-lipoprotein deficiency).

Area of Science:

• Lipidology
• Genetic metabolic disorders
• Cardiovascular disease

Background:

• Tangier disease is a rare autosomal recessive disorder characterized by severe deficiency of high-density lipoprotein (HDL) cholesterol.
• It results from mutations in the ABCA1 gene, leading to impaired cholesterol efflux from cells.
• Patients typically present with characteristic physical findings such as enlarged tonsils, peripheral neuropathy, and premature atherosclerosis.

Observation:

• A 38-year-old patient presented with asymptomatic hypocholesterolemia, mild hyperbilirubinemia, and splenomegaly.
• Lipoprotein analysis confirmed the diagnosis of Tangier disease (alpha-lipoprotein deficiency).
• This case represents the first documented instance of Tangier disease in the northeastern United States.

Findings:

• Despite being asymptomatic for atherosclerosis at age 38, the patient exhibited widespread tissue cholesterol ester deposition.
• A strong family history of atherosclerosis was noted, suggesting a genetic predisposition.
• The patient's hypocholesterolemia was a key indicator for diagnosing Tangier disease.

Implications:

• Tangier disease may be significantly underdiagnosed due to its rarity and often asymptomatic presentation.
• Hypocholesterolemia, particularly when accompanied by splenomegaly or a family history of cardiovascular disease, should raise suspicion for Tangier disease.
• Early diagnosis and management are crucial to mitigate the long-term risks of cholesterol accumulation and associated complications such as atherosclerosis.