Tangier disease (TD) is a rare lipoprotein metabolism disorder characterized biochemically by an almost complete absence of plasma high-density lipoproteins (HDL), and clinically by liver, spleen, lymph node and tonsil enlargement along with peripheral neuropathy in children and adolescents, and, occasionally, cardiovascular disease in adults.

The presence of erythrocytes with a mouth-shaped (stoma) area of central pallor on peripheral blood smear.