From the Guidelines
Primary erythromelalgia is a rare disorder characterized by episodes of burning pain, redness, and swelling in the extremities, particularly the feet and hands, with no identifiable underlying cause, also known as idiopathic erythromelalgia. According to the most recent study published in the Mayo Clinic Proceedings in 2023 1, primary erythromelalgia is a debilitating condition that can significantly impact a patient's quality of life, leading to increased morbidity and mortality. The study highlights the importance of effective treatment to alleviate symptoms and improve outcomes.
Key Characteristics of Primary Erythromelalgia
- Episodes of burning pain associated with erythema and warmth of the extremities
- Feet and hands are most commonly affected
- Pain can be severe and debilitating, leading to extreme behaviors to cool the affected areas
- Symptoms are often triggered by physical activity and exposure to warm temperatures
- Diagnosis may be missed due to intermittent symptoms and normal appearance of affected areas between episodes
Management of Primary Erythromelalgia
- Lifestyle modifications to avoid triggers such as exercise and increased ambient heat
- Pharmacologic treatments, including topical and systemic medications
- A multidisciplinary pain rehabilitation program should be considered for patients with refractory primary erythromelalgia whose lives have been severely affected by the condition 1
- Comprehensive pain rehabilitation centers offer an integrated team of providers, including physicians, psychologists, and occupational and physical therapists, to address physical and emotional functioning.
From the Research
Definition and Characteristics of Primary Eurythromyalgia
- Primary erythromelalgia is a rare, chronic, debilitating condition characterized by redness, warmth, and severe burning pain of the distal extremities, primarily affecting the feet and sometimes the hands 2, 3, 4, 5, 6.
- The condition is often precipitated by increases in temperature and exercise, and patients may obtain relief by immersing the affected extremity in cold water 2, 3, 4, 5.
- Primary erythromelalgia can be inherited in an autosomal dominant pattern, with mutations in the SCN9A gene, which encodes a voltage-gated sodium channel subtype Nav1.7, playing a key role in its pathogenesis 4, 6.
Clinical Presentation and Diagnosis
- The clinical onset of primary erythromelalgia often occurs in the first decade of life, with burning pain being the most predominant symptom 4.
- Diagnosis is made based on clinical manifestations, screening for mutations in the SCN9A gene, and exclusion of other treatable diseases or secondary erythromelalgia 4.
- Diagnostic methods may involve complete blood count, imaging studies, and thermograph, although there are no specific biomarkers for primary erythromelalgia 4.
Treatment and Management
- Treatment for primary erythromelalgia is often unsatisfactory and highly individualized, with frequently used pain-relieving drugs including sodium channel blockers such as lidocaine, carbamazepine, and mexiletine 2, 4, 5.
- Novel drugs with Nav1.7 selectivity, such as PF-05089771 and TV-45070, may be promising in ameliorating pain symptoms 4.
- Other treatment modalities, including gabapentin, aspirin, indomethacin, beta-blockers, and calcium channel antagonists, may also be used as therapeutic options 5.