Janet Bremen, age 13, of Rutland, Vt., for her question:

WHY DO SOME PEOPLE HAVE JAUNDICE?

Jaundice is a yellowish discoloration of the skin, the tissues

and the whites of the eyes. Jaundice comes as a result of an increased amount of bilirubin, a reddish yellow pigment, in the blood. Bilirubin is formed by the breakdown of hemoglobin, a pigment in red blood cells. Jaundice is not a disease but a symptom of various diseases.

The liver removes bilirubin from the blood stream and secretes it in the bile. Thus, jaundice results from either excessive production of bilirubin or reduced secretion of bile.

Many babies are born with physiologic jaundice, which occurs if the body cannot process all the bilirubin it produces. In host cases, this condition disappears by the time the baby is two weeks old.

Obstructive jaundice is caused by the blocking of the bile ducts. Gallstones may cause such a blockage.

Hepatocellular jaundice occurs when the liver is damaged so that it cannot secrete enough bile. Bilirubin collects in the body, then causing jaundice.