Mucous Cyst

Key Points
Type of cyst which typically affects the fingers
May be caused by abnormal mucin deposits in the skin, or develop in relation to osteoarthritis
Consists of a small lump with a smooth, shiny surface, and may exude a sticky, gelatinous fluid

Mucous cysts are a type of cyst with typically appear on the end of the finger at the nail base, though in some cases the knuckle in the area may become involved. The condition consists of a small lump, which varies in size, with a smooth, shiny surface. The cyst may exude a sticky, gelatinous fluid if expressed, and this fluid may contain blood.

Mucous cysts are caused by one of two factors. The condition may result from abnormal mucin deposits in the skin, or in relation to changes to the lining of joints in relation to osteoarthritis. Lesions forming in relation to osteoarthritis are a type of ganglion. The condition may affect anyone, regardless of age, gender, or ethnic group.

Differential Diagnosis (Other conditions with similar appearance)
Xanthomas
Epidermoid Cyst
Fibrokeratoma
Giant-cell tendon sheath tumor
Heberden node
Myxoid malignant fibrous Histiocytoma
Myxoid variant of Liposarcoma
Rheumatic nodule

Diagnosis
Key Points
Diagnosis based on the characteristic appearance of the affected area
Skin biopsy may be performed to rule out other conditions

Mucous cysts are typically diagnosed based on the characteristic appearance of the affected area. A skin Biopsy may be performed to rule out similar appearing conditions.

Treatment
Various treatments are available
*Cysts often recur, in spite of successful treatment

Mucous cysts respond well to various treatments. These include lancing and expressing the contents of the cyst, repeated firm pressure, cryotherapy, steroid Injections, sclerosant Injections, and surgical excision. However, in spite of successful treatment, cysts often recur and require further treatment.