Inside The Exam Room™ 12/04/2006
RAYNAUD’S SYNDROME: Part 1
By Mark Ombrellaro, MD
Living in Seattle where it is frequently cold and damp, a friend of mine asked that I write about Raynaud’s syndrome: a problem shared by her and various other friends. The topic for the next 2 weeks will focus on this subject, and are dedicated to them. Have you ever experienced the problem when the weather starts to get cooler, that your hands (and feet) turn white, blue, red, or all three in sequence? Do they get numb or tingle when this starts to happen? Are your hands and feet cold all the time? Have these same symptoms occurred when you are under stress or doing something as simple as holding a cold drink? These are some of the commonest manifestations of what is known as Raynaud’s syndrome.
Raynaud’s syndrome is a disorder where abnormal spasm or vasoconstriction occurs in the small digital arteries of the fingers and toes while the major peripheral pulses remain intact. The condition was first characterized by Maurice Raynaud in the late 1800’s where he described a series of patients with gangrene changes affecting the fingers on both hands, in the presence of normal pulses. He surmised that the condition was due to an over activity of the sympathetic nervous system affecting the blood supply to the fingers. As the name implies, the spasm of these small digital arteries tends to be a temporary, yet recurrent phenomena. Spasm of these small vessels prevents adequate arterial blood flow from reaching the tissue of the digits and causes them to turn pale. As the spasm continues, the blood retained in the digits gets further depleted of its oxygen content and the digits turn a blue hue. The lack of oxygen (ischemia) leads to a reflex response where the spasm relaxes and the flow is once again restored. This causes a red color to appear due to the temporary excess of flow within the digits. The magnitude and duration of the spasm effect can be variable and these cycles tend to occur repeatedly.
There are 2 basic types of Raynaud’s syndrome: primary and secondary. Primary Raynaud's is where the cause cannot be attributed to any other type of medical condition and is considered unknown. Characteristically, there is no evidence of atherosclerotic vascular disease in these individuals. Over 90% of Raynaud’s patients have a primary etiology. Most of the time, it is a benign disease and only in very rare circumstance will the spasms be severe enough to lead to tissue loss (ulceration or gangrene). The disease occurs in up to 15% of otherwise normal people and affects women 4 times more frequently than men. Symptoms can begin as early as the teenage years or up into one’s thirties. There also tends to be a higher incidence of symptomatic individuals in cooler climates and is unusual for individuals living in warm locations. Symptoms typically affect both hands and/or feet and peripheral pulses remain intact. To actually make the diagnosis of primary Raynaud’s syndrome, patients should have symptoms of vasospasm for at least 2 years and be found to have no other problem that could explain their symptoms. Raynauds does not appear to have a genetic predisposition. Patients taking beta blockers may aggravate their symptoms because the medication works by blocking peripheral vasodilatation.
In patients with longstanding primary Raynaud’s syndrome, the natural history is that approximately 1/6 will get worse, 1/6 will have complete resolution of their symptoms, and the rest remain stable or improved. Under the microscope, the digital arteries may look slightly thickened but for the most part, remain normal. A cool environment will often lead to vasoconstriction of the digital arteries in most people but this is especially problematic in Raynaud’s patients. The diagnosis is typically suggested by the patient’s history of coolness, numbness or tingling, or pain in the hands or fingers with cold exposure. Interestingly, the thumb tends to be spared from involvement for reasons which are not known. Symptoms are brought on by cold exposure in over 95% of cases while emotional distress is thought to initiate symptoms less than 5% of the time. Non invasive vascular testing can be helpful by measuring the blood flow wave form of the digital arteries both at rest and after immersing the fingers in cold water. Patients with Raynaud’s symptoms are found to have normal blood flow wave forms at rest, but after cold water exposure, the digital wave forms will become dampened or entirely flat line.