Raynaud syndrome

Raynaud syndrome, also known as Raynaud's phenomenon, is a medical condition in which the spasm of small arteries causes episodes of reduced blood flow to end arterioles. Typically the fingers, and, less commonly, the toes, are involved. Rarely, the nose, ears, nipples, or lips are affected. The episodes classically 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. The condition is named after the physician Auguste Gabriel Maurice Raynaud, who first described it in his doctoral thesis in 1862.
Episodes are typically triggered by cold or emotional stress. Primary Raynaud's is idiopathic (spontaneous and of unknown cause) and not correlated with another disease. Secondary Raynaud's is diagnosed given the presence of an underlying condition and is associated with an older age of onset. In comparison to primary Raynaud's, episodes are more likely to be painful, asymmetric and progress to digital ulcerations. 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 and stimulants. 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. There is little evidence that alternative medicine is helpful. Severe disease may in rare cases lead to complications, specifically skin sores or gangrene.
About 4% of people have the condition. Onset of the primary form is typically between ages 15 and 30. The secondary form usually affects older people. Both forms are more common in cold climates.
The condition can cause localized pain, discoloration (paleness), 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 (called pallor) 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 (rubor), 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 yet 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.
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. In a large genetic study two genes were identified that predispose for the condition: ADRA2A (alpha-2A-adrenergic receptor for adrenaline) and the transcription factor IRX1.
Smoking increases the 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.
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 syndrome 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.
Three main changes are seen in the mechanism of Raynaud's phenomenon which are reduced blood flow, blood vessel constriction, and neurogenic, inflammatory, and immune responses. It is induced by mental stress and a cold atmosphere. In all cases, the primary cause is an underlying hyperactivation of the sympathetic nervous system. Although, with different types, the exact pathophysiology differs. In the primary type, there is an increase in sensitivity due to the reasons mentioned above resulting in vasoconstriction. In the secondary type, normal activity of blood vessels is disrupted due to the same reasons mentioned above causing vasoconstriction which leads to ischemia and tissue death.
Distinguishing Raynaud's disease (primary Raynaud's) from Raynaud's phenomenon (secondary Raynaud's) is important. Looking for signs of arthritis or vasculitis, as well as several laboratory tests, may separate them. Nail fold capillary examination or "capillaroscopy" is one of the most sensitive methods to diagnose RS with connective tissue disorders, i.e. distinguish a secondary from a primary form objectively.
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.
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 (including passive smoking) and sympathomimetic drugs.
Medications can be helpful for moderate or severe disease.
Evidence does not support the use of alternative medicine, including acupuncture and laser therapy.
The prognosis of primary Raynaud syndrome is often very favorable, with no mortality and little morbidity overall. In some very rare cases, gangrene has been known to develop. The prognosis of secondary Raynaud is related to the course of the underlying disease, and how effective blood flow-restoring maneuvers are.