Raynaud’s phenomenon

Raynaud's phenomenon or, simply, Raynaud's, is a disorder characterized by decreased blood flow—usually to the fingers, and less frequently to the ears, toes, nipples, knees or nose. Vascular spasms usually occur as attacks in response to cold exposure, stress or emotional upset.

Raynaud's can occur alone (primary form) or may occur with other diseases (secondary form). The primary form of Raynaud's is the most common type, and usually begins between ages 15 and 25. It's less severe than the secondary form, and few people with this form develop another related condition.

The following are the most common symptoms of Raynaud's phenomenon:

• A pattern of color changes in the fingers as follows: pale/white followed by blue then red when the hands are warmed; color changes are usually preceded by exposure to cold or emotional upset
• Hands may become swollen and painful when warmed
• Ulcerations of the finger pads develop (in severe cases)
• Gangrene may develop in the fingers leading to amputation (in about 10 percent of the severe cases)

The exact cause of Raynaud's is unknown. One theory links blood disorders characterized by increased platelets or red blood cells that may increase the blood thickness. Another theory involves the special receptors in the blood that control the constriction of the blood vessels are shown to be more sensitive in individuals with Raynaud's.

Certain things can increase a person's risk for developing Raynaud's, including:

• Having an existing connective tissue or autoimmune disease
• Cigarette smoking (in men)
• Alcohol use (in women)

Raynaud's may occur with other diseases (secondary form). The diseases most frequently associated with Raynaud's are autoimmune or connective tissue diseases, among others, such as the following:

• Systemic lupus erythematous (lupus)
• Scleroderma
• CREST syndrome (calcium skin deposits, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasis)
• Buerger's disease
• Sjögren's syndrome
• Rheumatoid arthritis
• Occlusive vascular disease
• Polymyositis
• Cryoglobulinemia

Individuals who first experience Raynaud's phenomenon after ages 35 to 40 may be tested for an underlying disease.

There are no specific laboratory tests that can confirm a diagnosis of Raynaud's phenomenon. Instead, diagnosis is usually based on reported symptoms. Your doctor may perform a cold challenge test to bring out color changes in the hands or a nailfold capillaroscopy where your fingernail is examined under a microscope.

Tests to determine which form (primary or secondary) of Raynaud's phenomenon a patient may have include a medical exam, blood tests and a complete medical history. 

Although there is no cure for Raynaud's phenomenon, the disorder can often be successfully managed with proper treatment. Treatment may include:

• Preventive measures, such as avoiding cold exposure and wearing extra layers to keep warm, including warm gloves, socks, scarf and a hat 
• Smoking cessation
• Wearing finger guards over ulcerated fingers
• Avoiding trauma or vibration to the hand (such as vibrating tools)
• Medications that are usually used to treat high blood pressure (antihypertensive medications) may be given during the winter months (to help reduce constriction of the blood vessels)