What is Erythromelalgia?
Erythromelalgia is a medical condition where an individual experiences acute burning pain, marked redness (erythema), with increase in the temperature of the skin, especially of the feet and hands. Erythromelalgia is also considered a type of neuropathic pain syndrome where the pain is associated with medical conditions that affect the nerves themselves. The small blood vessels become dilated and congested with blood. Erythromelalgia is usually bilateral, i.e. affecting both the sides of the body; however, it may also be unilateral, i.e. involving only one side of the body. The course of this disease differs greatly from patient to patient. The onset of the symptoms of Erythromelalgia in some patients can be gradual and this condition can remain mild for many years. In some patients, there may be acute or sudden onset of Erythromelalgia, where it becomes severe over a period of time.
The exact cause of erythromelalgia is not known. The cause of this condition is thought to be vasomotor abnormalities or problems with the constriction/narrowing and dilation/widening of some blood vessels, which cause abnormalities or disturbance in the blood flow to the extremities. Erythromelalgia can be a primary or an isolated condition or it can occur secondary to different underlying medical conditions. The cause of primary erythromelalgia is not known and it can occur randomly or can be familial indicating an autosomal dominant inheritance.
Types of Erythromelalgia
Erythromelalgia is classified into primary erythromelalgia and secondary erythromelalgia. Another classification is early-onset erythromelalgia and late-onset erythromelalgia.
- Primary Erythromelalgia: The cause of this is genetic mutation where the symptoms are often triggered by temperatures changes, heat, over-exertion, spicy foods, alcohol and exercise.
- Secondary Erythromelalgia: This occurs as a result of certain autoimmune disorders, mercury poisoning, mushroom poisoning, hypercholesterolemia, and essential thrombocytosis.
Causes of Erythromelalgia
The exact cause of erythromelalgia is not known in majority of the cases. Primary erythromelalgia often develops spontaneously without any related underlying disease. This type of erythromelalgia is also referred to as 'idiopathic erythromelalgia'. The cause of secondary erythromelalgia is medical conditions, such as neurological diseases (peripheral neuropathy, multiple sclerosis), autoimmune diseases (diabetes mellitus, lupus) and more commonly myeloproliferative disorders where there is excessive production of cells by the bone marrow, e.g. polycythemia vera, essential thrombocythemia. Patient experiences erythromelalgia before the myeloproliferative disorder appears in majority of the cases.
Patients having early-onset erythromelalgia will develop it before they reach 25 years of age. Even though early-onset erythromelalgia is of unknown origin in majority of the patients, in some cases, it can be traced back through many generations of the family. This is thought to occur due to genetic mutations. Late-onset erythromelalgia tends to develop in individuals who are around 40 to 60 years of age and it presents as primary erythromelalgia in more than half of the patients.
Some of the potential causes of Erythromelalgia are:
- Infections such as fungal or others.
- Heavy metal poisoning.
- Deficiency of nutrients such as pantothenic acid.
- Neurological disorders.
- Excessive sweating, particularly on the feet.
- Wearing tight socks or shoes for prolonged periods of time.
Signs & Symptoms of Erythromelalgia
- Erythromelalgia is characterized by painful, red, warm hands or feet, which is triggered by warming or downward hanging of the limbs. It is relieved with elevation and cooling.
- The lower extremities including the toes and soles of the feet and are most commonly affected in Erythromelalgia. In rare cases, the pain radiates up to the knees.
- The involvement of the upper extremity includes the fingers and hands. Commonly, both the feet and hands are involved in Erythromelalgia and there is bilateral involvement, i.e. both the sides of the body are affected.
- There may be unilateral involvement also, where only one side of the body is affected in Erythromelalgia. This is particularly seen in secondary cases.
- Patients suffering from Erythromelalgia may experience symptoms of continuous burning; whereas some patients may have bouts or flare-ups of this condition.
- The symptoms of flare-ups or bouts can last for minutes to days and usually occur late in the day and persist throughout the night.
- Patient suffering from Erythromelalgia experiences symptoms of itching sensation during the beginning of the attack, which then progresses to more severe pain accompanied with burning sensation.
- When the attack occurs, the extremities become tender, warm and swollen. There is a dusky red appearance to it and the skin can also appear mottled.
- Symptoms of Erythromelalgia can also appear in the ears, face and other parts of the body; however, this is less frequent.
- In some cases of Erythromelalgia, the pain may be so acute that the patient is not able to walk.
- Cooling the affected extremity with a fan or by immersing it in cold water helps in relieving the symptoms of Erythromelalgia. Elevating the affected extremity also helps in relieving the symptoms.
- Sometimes, the symptoms of Erythromelalgia worsen so much that the patient has difficulty in performing daily normal functioning and the quality of life is greatly affected.
- Some patients may also need to avoid warm weather and may also have to change their residence to cooler climates. Many of the patients will not be able to wear closed shoes and socks, even in winter.
- In some cases, patients suffering from Erythromelalgia can also become practically housebound due to continuous pain and flare-ups.
Diagnosis of Erythromelalgia
Investigations need to be done to identify the underlying causes in all the new cases of Erythromelalgia. Erythromelalgia can also be an early sign of thrombocythemia or polycythemia where the symptoms appear before the diagnosis is made. If the cause is myeloproliferative disorders, then patient can experience dramatic relief with the use of aspirin. This is a useful aid in diagnosis.
Tentative diagnosis of Erythromelalgia can be made based on the symptoms. Immersion of the affected region in hot water for about 20 to 30 minutes can trigger an attack and helps in confirming the diagnosis. When no known underlying cause has been found, then the erythromelalgia is considered primary.
Treatment for Erythromelalgia
If the underlying cause is found in secondary erythromelalgia, then it must be treated. Treating the symptoms of primary erythromelalgia, as well as secondary erythromelalgia comprises of conservative measures, drug therapy and surgical intervention.
- Conservative treatment for Erythromelalgia include cooling of the extremity or elevating the extremity to relieve the symptoms. Care should be taken during cold water immersions; however, this will give temporary relief and can lead to other serious problems. A vicious cycle occurs due to frequent immersion into cold water, as the temperature changes can cause reactive flaring along with wasting away of the skin, infection, non-healing ulcers, gangrene and amputation.
- Topical treatment for Erythromelalgia with the use of capsaicin cream can give some relief and has varying results.
- Different types of oral medications are beneficial in relieving symptoms of Erythromelalgia and these include:
- Aspirin, which promptly relieves erythromelalgia related symptoms which occur as a result of myeloproliferative disorders.
- Tricyclic antidepressants, such as imipramine and amitriptyline also help in relieving the symptoms of Erythromelalgia.
- Serotonin re-uptake inhibitors, such as sertraline, venlafaxine, paroxetine and fluoxetine can be given for relief of symptoms.
- Anticonvulsants, such as gabapentin are also prescribed.
- Prostaglandins, such as misoprostol can also be given.
- Calcium antagonists, which include diltiazem and nifedipine, can also be prescribed.
- Patient can also be given intravenous infusions of nitroprusside, lidocaine and prostaglandin.
Different patients respond differently to drug therapy. There is no proven single therapy which is known to be consistently effective in treating Erythromelalgia. In some cases, patients may have spontaneous remissions also.
Surgical Treatment in Erythromelalgia
If the above treatments measures do not provide relief then surgery may be needed to treat Erythromelalgia. Surgical sympathectomy is a procedure where the sympathetic nerve fibers are selectively cut. In this surgical procedure, the nerve endings which transmit the pain signals from the hands and feet are cut. This surgery carries serious risks; however, this procedure is more beneficial in patients whose quality of life has been severely affected due to erythromelalgia.
Diet in Erythromelalgia
Diet plays an important role in treating and managing erythromelalgia. Foods which are rich in vitamin B should be consumed, as they help in boosting the immune system along with providing relief from symptoms of erythromelalgia. Diet which should be followed in erythromelalgia should comprise of the following foods:
- Brown rice.
- Whole grains.
- Dairy products, such as butter, milk and cheese.
- Different types of yellow and green vegetables.
Lifestyle Modifications & Herbal Remedies for Erythromelalgia
The following modifications in the patient's lifestyle help in bringing relief in erythromelalgia and include:
- It is important to relax along with elevating both the feet. Placing cold compresses to the affected region also benefits in relieving the symptoms of Erythromelalgia. This should be done for about 20 to 30 minutes in a week. It will help in preventing and minimizing the intensity of erythromelalgia.
- Taking a bath every day, especially to the region of the feet using hawthorn or sanicle herbs, helps in alleviating the symptoms of erythromelalgia. Around 20 to 25 drops of this herb should be mixed in the bath water. This can also be beneficial in patients who suffer from a recurring burning sensation.
- A combination of pepper and eucalyptus oil used 4 to 5 times daily also helps in providing relief from the symptoms of erythromelalgia. This is an effective remedy in getting rid of the burning and painful sensations present in the body.