C

Candida

Candida is the name for a group of yeasts (a type of fungus) that commonly infect the skin. The name "candida" refers to the white color of the organisms in culture. Candidal infection is known as "candidiasis", "candidosis" or "moniliasis". Candida depends on a living host for survival. It is a normal inhabitant of the human digestive tract from early infancy, where it lives without causing any disease most of the time. However, if the host's defences are lowered, the organism can cause infection of the mucosa (the lining of the mouth, anus and genitals), the skin, and rarely, deep-seated infection.

Capillaritis

Capillaritis is the name given to a harmless skin condition in which there are reddish -brown patches caused by leaky capillaries. It is also known as pigmented purpura. The capillaries are small blood vessels near to the skin surface. For unknown reasons they sometimes become inflamed. Blood cells may pass through small gaps that arise between the cells, which make up the capillary walls. The result is tiny red dots appear on the skin, described as cayenne pepper spots. They group together to form a flat red patch, which becomes brown and then slowly fades away over weeks to months.

Cat Scratch Disease

CSD is a benign self-limited zonotic infection, characterized by a primary skin or eye lesion, following cat scratches or contact with a cat and subsequent tender lymph nodes. The inoculation site resemble a pimple which may ulcerate. Occasionally there may be high fevers and severe systematic symptoms.

Cellulitis

Cellulitis is a sudden spreading infection of dermal and subcutaneous tissues (tissues underneath the skin) characterized by a red hot tender area of skin, often at the site of bacterial entry, caused most frequently by group A beat-hemolytic streptococci or staphylococcus aureus. Patients often have associated malaise, anorexia, fever, and chills. If untreated cellulitis can be life threatening.

Chickenpox

(See varicella)

Chilblains

Chilblains are itchy and/or tender red or purple bumps that occur as a reaction to cold. They are also known as pernio. Chilblains occur several hours after exposure to the cold in temperate humid climates. They are sometimes aggravated by sun exposure. Cold causes constriction of the small arteries and veins in the skin and rewarming results in leakage of blood into the tissues and swelling of the skin.

Chloasma

(See melasma)

Chloracne

Chloracne is a rare acne-like skin condition caused by certain toxic chemicals including the dioxins. It develops a few months after swallowing, inhaling or touching the responsible agent.

Comedone Naevus

A comedone naevus is an unusual type of birthmark in which there is a localized collection of comedones. The cause is unknown. The comedones can arise from normal sized, enlarged or small sebaceous glands or even from sweat ducts. They may be found on any site of the body. Rarely, at puberty or later, a comedone naevus may develop inflammatory acne lesions within it

Cryotherapy

Cryotherapy is a treatment in which skin lesions are frozen using liquid nitrogen or other cryogens. Cryotherapy is used for removing warts, seborrhoeic keratoses, and other benign lesions, also solar keratoses (sun damage), and small skin cancers such as basal cell carcinomas, and squamous cell carcinomas.

Cutaneous T Cell Lymphoma

(Mycoses Fungoides) CTCL is a termthat applies to a T cell lymphoma first manifested in the skin but with time involves the blood, lymph nodes and internal organs. Often the intial rash is not specific and may resemble eczema for years before diagnosed. Treatments initially are very conservative and include light therapy and topical creams.

Cysts

A cyst is a harmless, sac-like growth in the deeper layers of the skin. The cyst sac is filled with a soft, whitish brown material that sometimes oozes out onto the skin's surface. It is not known why cysts appear, or why some persons get many of them.