A carbuncle is a cluster of connected boils that forms under the skin and contains pus. It is usually caused by a bacterial infection, most commonly involving Staphylococcus aureus. Carbuncles can be painful and may drain pus through one or more openings in the skin. They commonly develop on areas such as the back of the neck, shoulders, thighs or…

Carpal tunnel syndrome (CTS) is a condition caused by compression or irritation of the median nerve as it passes through the carpal tunnel in the wrist. It can cause numbness, tingling, pain and weakness in the hand and fingers. Symptoms often develop gradually and may become more noticeable at night, during repetitive hand activities or when holding the wrist in…

Cellulitis is a bacterial infection of the deeper layers of the skin, usually involving the dermis and tissues beneath the skin. It can develop anywhere on the body but commonly affects the lower legs and feet. Cellulitis usually develops when bacteria enter the skin through a cut, crack, wound, insect or animal bite, or another break in the skin. The…

Cervicitis is inflammation of the cervix, the lower, narrow part of the uterus that connects the uterus with the vagina. It may occur because of an infection, particularly sexually transmitted infections (STIs), or because of irritation or other noninfectious causes. Common infectious causes include chlamydia and gonorrhea, while other infections such as Trichomonas vaginalis and certain vaginal infections may also…

A chalazion is a usually painless lump that develops in the eyelid when an oil-producing meibomian gland becomes blocked. These glands help keep the surface of the eye lubricated. A chalazion may develop on either the upper or lower eyelid. It can initially cause swelling and tenderness and may later become a firm, painless lump. Many chalazia improve on their…