Question: What is (are) Erythromelalgia ?
Answer: Erythromelalgia (EM) is a rare condition characterized by episodes of burning pain, warmth, swelling and redness in parts of the body, particularly the hands and feet. This condition may occur spontaneously (primary EM) or secondary to neurological diseases, autoimmune diseases, or myeloproliferative disorders (secondary EM). Episodes may be triggered by increased body temperature, alcohol, and eating spicy foods. About 15% of cases are caused by mutations in the SCN9A gene and are inherited in an autosomal dominant manner. Other cases may be caused by unidentified genes or by non-genetic factors. Treatment depends on the underlying cause and may include topical and/or oral medications. In some cases, the condition goes away without treatment.
Source: GARD

Question: What are the symptoms of Erythromelalgia ?
Answer: What are the signs and symptoms of Erythromelalgia? Currently it is very difficult to predict how a person's primary erythromelalgia will affect them overtime. The cause of primary erythromelalgia is not well understood. Much of the literature regarding the long term outlook for people with idiopathic primary erythromelalgia is compiled from individual case reports. Erythromelalgia is usually a chronic or persistent condition, however there have been cases that have fully resolved with time. Many people with primary erythromelalgia have stable symptoms, however cases of progressive disease (symptoms worsening overtime) have also been described. Pain is a characteristic/classic feature of primary erythromelalgia. Unfortunately we were not able to find information specific to painless cases of this disorder, and outcomes of these individuals. The Human Phenotype Ontology provides the following list of signs and symptoms for Erythromelalgia. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Dysautonomia 5% Abnormality of the musculature - Autosomal dominant inheritance - Blurred vision - Constipation - Diarrhea - Hyperhidrosis - Juvenile onset - Myalgia - Pain - Palpitations - Xerostomia - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Erythromelalgia ?
Answer: What causes erythromelalgia? About 15% of cases of erythromelalgia are caused by mutations in the SCN9A gene. The SCN9A gene gives instructions for making part of a sodium channel which carries sodium into cells and helps them make and transmit electrical signals. These sodium channels are found in nerve cells that transmit pain signals to the spine and brain. Mutations that cause erythromelalgia cause increased transmission of pain signals, leading to the signs and symptoms of the condition. In some of these cases, an affected individual inherits the mutation from an affected parent. In other cases, a new mutation occurs for the first time in an individual with no history of the condition in the family. In the remainder of cases, the exact underlying cause is not currently known. Evidence suggests that it results from abnormalities in the normal narrowing and widening of certain blood vessels, leading to abnormalities in blood flow to the hands and feet. There may be a variety of non-genetic causes, or mutations in other genes that have not yet been identified.
Source: GARD

Question: How to diagnose Erythromelalgia ?
Answer: How is erythromelalgia diagnosed? Erythromelalgia can be diagnosed through a clinical exam and medical history. Additional tests may include a skin biopsy and thermography to evaluate skin temperature. Blood tests or other studies may be done to rule out other conditions that can cause similar symptoms. There is not a specific type of doctor that always diagnoses and treats erythromelalgia. A variety of specialists (alone or in combination) may be involved in the diagnosis and treatment of this condition. These may include vascular specialists, hematologists, dermatologists, neurologists, rheumatologists, and other types of physicians. The type of specialist that is appropriate may depend on the underlying cause when secondary erythromelalgia is present. Since erythromelalgia is a rare disease, many doctors are not familiar with the condition. The Erythromelalgia Association offers resources and support for individuals looking for more information about the diagnosis of the condition.
Source: GARD

Question: What are the treatments for Erythromelalgia ?
Answer: What treatment is available for erythromelalgia? There appear to be several subtypes of erythromelalgia and different subtypes respond to different therapies. Treatment consists of a trying various approaches until the best therapy is found. Patients respond quite variably to drug therapy and no single therapy has proved consistently effective. Spontaneous remissions have also been known to occur. Drugs shown to be effective in relieving pain in some individuals include: aspirin, prostaglandins (misoprostol), serotonin-norepinephrine reuptake inhibitors (venlafaxine and sertraline) and selective serotonin reuptake inhibitors (SSRIs), anticonvulsants (gabapentin), sodium channel blockers, carbamazepine, tricyclic antidepressants (amitriptyline and imipramine), calcium antagonists (nifedipine and diltiazem), magnesium, sodium nitroprusside infusion, and cyclosporine. Other treatments include: cooling or elevating the extremity, topical treatment with capsaicin cream, and surgical sympathectomy (a procedure where the sympathetic nerve fibers are selectively cut).Avoidance of triggers (such as warmth, prolonged standing, etc.) may reduce the number or severity of flare ups.
Source: GARD