Japanese adult siblings with Tangier disease and statistical analysis of reported cases

A 28 year old Japanese female was admitted to our university hospital because of extremely low plasma cholesterol levels (50mg/dl). On physical examination, tonsillar remnants and several flat patches of yellow-orange lymphoid tissues in the pharynx were found. Her plasma HDL was as low as 2.4 mg/dl. Laparoscopic findings showed typical yellow patches on the surface of the liver, and liver biospy specimens contained cholesterol esters demonstrated by the Schultz reaction. Colonofiberscopy showed orange-brown spots present throughout the rectum. Histologically, "foam cells" were recognized in the lymphoid tissue of the pharynx and rectal mucosa. Her sister, 26 years old, also revealed yellow-orange tonsils, low plasma cholesterol levels (39mg/dl) and low plasma HDL levels (8mg/dl), and was also diagnosed as Tangier disease. From a statistical analysis of the reported cases, it is noteworthy that yellow-orange tonsils, which were said to be the hallmark of Tangier disease, were not found in 20% of the patients. However, it is important that we could find rectal mucosa studded with orange-brown spots in all of the cases examined, and it contained "foam cells" histologically. It was concluded that when we suspect Tangier disease on account of hypocholesterolemia, we must first do a proctoscopic examination.