Raynaud's disease

Raynaud's disease (RAY-noz) is a vascular disorder that affects blood flow to the extremities (the fingers, toes, nose and ears) when exposed to cold temperatures or in response to psychological stress. It is named for Maurice Raynaud (1834 - 1881), a French physician who first described it in 1862.

Symptoms


The symptoms include several cyclic color changes:


 * 1) When exposed to cold temperatures, the blood supply to the fingers or toes, and in some cases the nose or earlobes, is markedly reduced; the skin turns pale or white (called pallor), and becomes cold and numb.
 * 2) When the oxygen supply is depleted, the skin colour turns blue (called cyanosis).
 * 3) These events are episodic, and when the episode subsides or the area is warmed, the blood flow returns and the skin colour first turns red (rubor), and then back to normal, often accompanied by swelling and tingling.

All three colour changes are observed in classic Raynaud's disease. However, not all patients see all of the aforementioned colour changes in all episodes, especially in milder cases of the condition. Symptoms are thought to be due to reactive hyperemias of the areas deprived of blood flow.

Disease vs. phenomenon
It is important to distinguish Raynaud's disease from Raynaud's phenomenon. In order to diagnose these two forms of Raynaud's, a doctor may look for signs of arthritis or vasculitis, and may conduct a number of laboratory tests.

Primary Raynaud's (disease)
Raynaud's disease, or "Primary Raynaud's", is diagnosed if the symptoms are idiopathic, that is, they occur by themselves and not in association with other diseases. Some refer to Primary Raynaud's disease as "being allergic to coldness". It often develops in young women in their teens and early adulthood. Primary Raynaud's is thought to be at least partly hereditary, although specific genes have not yet been identified.

Secondary Raynaud's (phenomenon)
Raynaud's phenomenon (RP), or "Secondary Raynaud's", occurs secondary to a wide variety of other conditions. The most common are connective tissue disorders such as systemic lupus erythematosus, arthritis, scleroderma/systemic sclerosis/CREST syndrome. Other rheumatic diseases frequently associated with RP include Rheumatoid Arthritis and Sjogren's syndrome.

Additional causes include obstructive arterial disease and carpal tunnel syndrome. Medications, such as beta-blockers and ergotamine, may also be responsible.

Patients with Secondary Raynaud's can also have symptoms related to their underlying diseases. RP is the initial symptom that presents for 70% of patients with scleroderma, a skin and joint disease.

In contrast to the disease form, this type of Raynaud's can, in extreme cases, progress to necrosis or gangrene of the fingertips.

Pathophysiology
Raynaud's disease is an exaggeration of vasomotor responses to cold or emotional stress. More specifically, it is a hyperactivation of the sympathetic nervous system, causing extreme vasoconstriction of the peripheral blood vessels, leading to tissue hypoxia. Chronic, recurrent cases of Raynaud's can result in atrophy of the skin, subcutaneous tissues, and muscle. It can also (rarely) cause ulceration and ischemic gangrene.

Prevention
Patients with Raynaud's disease should keep their extremities warm by wearing gloves and socks. Patients are advised to avoid stressful situations, touching of cold objects, and artificially cold environments, such as refrigerated or highly air conditioned spaces. Patients are also advised to avoid medications and foods that can constrict blood vessels, such as decongestants and caffeinated beverages, as well as smoking.

Treatment
The severity of the disease runs from mild to severe. In people with mild cases, it may be just an annoyance. Heatbands and hand warmers may be used on the wrists to warm the blood flowing to the hands. More serious cases can require medical intervention due to the risks of gangrene and possible digital amputation.

Treatment for Raynaud's disease may include prescription medicines that dilate blood vessels, such as calcium channel blockers (nifedipine) or diltiazem. Fluoxetine, a selective serotonin reuptake inhibitor, and other antidepressant medications may reduce the frequency and severity of episodes.

Milder cases of Raynaud's can often be addressed by biofeedback or other techniques to help control involuntary body functions like skin temperature. In severe cases, a sympathectomy procedure can be performed. Here, the nerves that signal the blood vessels of the fingertips to constrict are surgically cut. Microvascular surgery of the affected areas is another possible therapy.