Erythromelalgia (EM) is a rare, debilitating condition characterized by episodic burning pain, erythema, and increased skin temperature, typically affecting the distal extremities. EM significantly impairs quality of life (QoL) and may lead to functional disability. Although its pathophysiology is not fully understood, proposed mechanisms include small fiber nerve dysfunction and dysregulation of the sympathetic nervous system. Management remains challenging, with no universally effective treatment currently available. We present three patients with refractory lower extremity erythromelalgia treated with lumbar sympathetic block (LSB). All patients had chronic treatment-refractory symptoms and had failed multiple prior treatments, including neuropathic medications and conservative measures. Bilateral L3 LSBs were performed using a standardized approach. Two patients experienced substantial symptom improvement, with reported reductions in pain intensity and a prolonged benefit lasting several months. One patient demonstrated partial, short-term improvement. Repeated LSB procedures were performed in cases of symptom recurrence. In this retrospective case series, LSB was associated with symptomatic improvement in selected erythromelalgia patients, potentially by modulating sympathetic activity and regional blood flow. However, given the small sample size and retrospective design, no conclusions regarding efficacy can be drawn. Further studies are needed to better define patient selection criteria and long-term outcomes.
Erythromelalgia, a rare cutaneous pain syndrome, is characterized by acral burning pain and flushing, often alleviated by cold and rest. Primary erythromelalgia is caused by gain-of-function mutations of genes encoding for sodium channels, resulting in hyperexcitability of pain signaling neurons. Autoimmunity and hematologic dyscrasias such as thrombocythemia have been implicated in secondary erythromelalgia. The pathology of this rare disease remains poorly defined. The Weill Cornell dermatopathology database was analyzed for acral biopsies procured from patients here there was a clinical concern for erythromelalgia. We identified 9 patients with clinical diagnoses of erythromelalgia who had a skin biopsy from an affected area. The female-to-male ratio was 2:1. Three of 9 individuals had concurrent diagnoses of autoimmune disease including vitiligo, lupus erythematosus, and psoriatic arthritis. Biopsies showed superficial vascular ectasia in association with microvascular C5b-9 and variable upregulation of type I interferon expression in endothelial cells. CD56 stain revealed diminished autonomic innervation of the eccrine coil and arteries, mirroring similar autonomic denervation seen in small fiber neuropathy. This study suggests that erythromelalgia is a dysautonomia syndrome with reproducible findings on biopsy, hallmarked by vascular ectasia and denervation of the eccrine coil and arteries. In addition, there is a potential link to immune and nonimmune-based microvascular compromise.
Extreme thrombocytosis is a major risk factor for excessive bleeding and for thrombosis, either of which can complicate cardiovascular surgical and interventional procedures. Extreme thrombocytosis can also cause an unusual syndrome, erythromelalgia, that results in a type of chronic microvascular occlusive arterial disease. We present the differential diagnosis of conditions that may lead to extreme thrombocytosis, 3 cases (each of which illustrates a different potential complication), and a review of the pertinent medical literature. Correcting excessive thrombocytosis is typically not difficult, whether electively or acutely, and effective therapy usually controls thrombosis and excessive hemorrhage post-procedurally.
