Raynaud syndrome


Raynaud syndrome, also known as Raynaud's phenomenon, is a medical condition in which spasm of arteries cause episodes of reduced blood flow. Typically, the fingers, and less commonly the toes, are involved. Rarely, the nose, ears, or lips are affected. The episodes result in the affected part turning white and then blue. Often, numbness or pain occurs. As blood flow returns, the area turns red and burns. The episodes typically last minutes, but can last several hours.
Episodes are often triggered by cold or emotional stress. Primary Raynaud's, aka idiopathic, means that it is spontaneous and unrelated to another disease. Secondary Raynaud's occurs as a result of another condition. Secondary Raynaud's can occur due to a connective-tissue disorder, such as scleroderma or lupus, injuries to the hands, prolonged vibration, smoking, thyroid problems, and certain medications, such as birth control pills. Diagnosis is typically based on the symptoms.
The primary treatment is avoiding the cold. Other measures include the discontinuation of nicotine or stimulant use. Medications for treatment of cases that do not improve include calcium channel blockers and iloprost. Little evidence supports alternative medicine. Severe disease may rarely be complicated by skin sores or gangrene.
About 4% of people have the condition. Onset of the primary form is typically between ages 15 and 30 and occurs more frequently in females. The secondary form usually affects older people. Both forms are more common in cold climates. It is named after the French physician Maurice Raynaud, who described the condition in 1862.

Signs and symptoms

The condition can cause localized pain, discoloration, and sensations of cold and/or numbness.
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 and becomes cold and numb.
These events are episodic, and when the episode subsides or the area is warmed, the blood flow returns, and the skin color first turns red, and then back to normal, often accompanied by swelling, tingling, and a painful "pins and needles" sensation. All three color changes are observed in classic Raynaud's. However, not all patients see all of the aforementioned color changes in all episodes, especially in milder cases of the condition. The red flush is due to reactive hyperemia of the areas deprived of blood flow.
In pregnancy, this sign normally disappears due to increased surface blood flow. Raynaud's has occurred in breastfeeding mothers, causing nipples to turn white and painful.

Causes

Primary

Raynaud's disease, or primary Raynaud's, is diagnosed if the symptoms are idiopathic, that is, if 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.
Smoking increases frequency and intensity of attacks, and a hormonal component exists. Caffeine, estrogen, and nonselective beta-blockers are often listed as aggravating factors, but evidence that they should be avoided is not solid.

Secondary

Raynaud's phenomenon, or secondary Raynaud's, occurs secondary to a wide variety of other conditions.
Secondary Raynaud's has a number of associations:
Raynaud's can precede these other diseases by many years, making it the first presenting symptom. This may be the case in the CREST syndrome, of which Raynaud's is a part.
Patients with secondary Raynaud's can also have symptoms related to their underlying diseases. Raynaud's phenomenon is the initial symptom that presents for 70% of patients with scleroderma, a skin and joint disease.
When Raynaud's phenomenon is limited to one hand or one foot, it is referred to as unilateral Raynaud's. This is an uncommon form, and it is always secondary to local or regional vascular disease. It commonly progresses within several years to affect other limbs as the vascular disease progresses.

Mechanism

Its pathophysiology includes hyperactivation of the sympathetic nervous system causing extreme vasoconstriction of the peripheral blood vessels, leading to tissue hypoxia.

Diagnosis

Distinguishing Raynaud's disease from phenomenon is important. Looking for signs of arthritis or vasculitis, as well as a number of laboratory tests, may separate them. If suspected to be secondary to systemic sclerosis, one tool which may help aid in the prediction of systemic sclerosis is thermography.
A careful medical history will seek to identify or exclude possible secondary causes.
To aid in the diagnosis of Raynaud's phenomenon, multiple sets of diagnostic criteria have been proposed. Table 1 below provides a summary of these various diagnostic criteria.
Recently, International Consensus Criteria were developed for the diagnosis of primary Raynaud's phenomenon by a panel of experts in the fields of rheumatology and dermatology.

Management

Secondary Raynaud's is managed primarily by treating the underlying cause, and as primary Raynaud's, avoiding triggers, such as cold, emotional and environmental stress, vibrations and repetitive motions, and avoiding smoking and sympathomimetic drugs.

Medications

Medications can be helpful for moderate or severe disease.
Evidence does not support the use of alternative medicine, including acupuncture and laser therapy.

Prognosis

The prognosis of primary Raynaud syndrome is often very favorable, with no mortality and little morbidity. However, a minority develops gangrene. The prognosis of secondary Raynaud is dependent on the underlying disease, and how effective blood flow-restoring maneuvers are.