Detailed information on actinic keratosis, including causes and treatment.

Detailed information on keratosis pilaris, including symptoms, diagnosis, and treatment.

Detailed information on kidney disorders

Kidney failure happens when damage results in loss of normal kidney function. It may also be called end stage renal disease (ESRD).

A kidney stone is a hard, pebble-like deposit that forms in 1 or both kidneys. It may be as small as a grain of sand or as large as a pearl. Some are as big as golf balls. A stone may be smooth, irregular in shape, or jagged. Most are yellow or brown in color. There are different types of kidney stones.

Detailed information on kidney transplantation.

Common knee problems include sprains, strains, torn cartilage, and arthritis.

A spine affected by kyphosis has a forward curvature of the back bones (vertebrae) in the upper back area, giving an abnormally rounded or humpback appearance.