Erythromelalgia

Raynaud's syndrome is a common finding in many autoimmune conditions. Accurately diagnosing Raynaud's, and differentiating it from mimicking conditions, is imperative in rheumatologic diseases. Raynaud's syndrome and Raynaud's mimickers, especially painful Raynaud's mimickers, can prove a diagnostic challenge for the practicing rheumatologist. Painful Raynaud's mimickers can lead to increased patient stress and unnecessary medical work up; Healthcare providers need to be aware of Raynaud's mimickers when evaluating patient concerns of skin color changes and pain...

OBJECTIVE: Erythromelalgia is a rare, highly debilitating disorder characterised by severe episodes of discomfort, erythema, and desquamation of the extremities. Its causes include genetic factors, medications, and several underlying medical conditions. This paper describes a novel cause of erythromelalgia through a case report and literature review. CASE DESCRIPTION: A 47-year-old Caucasian man presented with a two-year history of intermittent pain, redness and desquamation of the hands...

BACKGROUND: Erythromelalgia, which has primary and secondary presentations, causes heat, pain, and redness in the skin. The condition seems to have an autonomic basis, with vasomotor dysfunction causing dilatation of some blood vessels and constriction of others. No consistently effective treatments have been reported. Anticonvulsant, antidepressant, antihistamine, anti-inflammatory, antihypertensive, analgesic, nutritional, and topical approaches have been tried as were lidocaine infusions, nerve blocks, and thoracic and lumbar sympathectomies...

Botulinum neurotoxin type A BoNT/A is used off-label as a third line therapy for neuropathic pain. However, the mechanism of action remains unclear. In recent years, the role of voltage-gated sodium channels (Nav) in neuropathic pain became evident and it was suggested that block of sodium channels by BoNT/A would contribute to its analgesic effect. We assessed sodium channel function in the presence of BoNT/A in heterologously expressed Nav1.7, Nav1.3, and the neuronal cell line ND7/23 by high throughput automated and manual patch-clamp...

No abstract text is available yet for this article.

Erythromelalgia is a rare syndrome with a generally unknown etiology. Whether primary or secondary, this condition is characterized by paroxysmal episodes of erythema, pain, and heat in the extremities. We report two cases of erythromelalgia occurring after the initiation of treatment with infliximab. The first case involves a 38-year-old patient who had been followed since August 2022 for ileocolonic Crohn's disease classified as A2L3B3 according to the Montreal classification, which was resistant to treatment and required infliximab therapy...

INTRODUCTION AND IMPORTANCE: Essential thrombocythemia (ET) is a rare chronic myeloproliferative hematologic disorder, leading to an elevated platelet count. Two-thirds of patients are asymptomatic during their lifetime, while others may experience symptoms like redness, congestion, and erythromelalgia after long symptom-free intervals. CASE PRESENTATION: The authors present a rare instance of a 55-year-old female who, despite receiving aspirin and losartan treatment, eventually developed digital gangrene...

Although warmth is a key sign of inflammatory skin lesions, an objective assessment and follow-up of the temperature changes are rarely done in dermatology. The recent availability of accurate, sensitive and cost-effective thermography devices has made the implementation of thermography in clinical settings feasible. The aim of this scoping review is to summarize the evidence around the value and pitfalls of infrared thermography (IRT) when used in the dermatology clinic. A systematic literature search was done for original articles using IRT in skin disorders...

Erythromelalgia (EM) is a rare disease, which is still poorly characterized. In the present paper, we compared the hand perfusion of one female EM patient, under challenges, with a healthy control group. Using a laser Doppler flowmeter (LDF) with an integrated thermal probe, measurements were taken in both hands at rest (Phase I) and after two separate challenges-post-occlusive hyperemia (PORH) in one arm (A) and reduction of skin temperature (cooling) with ice in one hand (B) (Phase II). The final measurement periods corresponded to recovery (Phases III and IV)...

An 18-year-old female with a history of atopic march, hyperhidrosis, and eosinophilic esophagitis was diagnosed with erythromelalgia and gastrointestinal dysautonomia secondary to presumed autoimmune small fiber neuropathy. The patient experienced significant clinical improvements after the initiation of intravenous immunoglobulin therapy, supporting an underlying autoimmune disorder.

No abstract text is available yet for this article.

Voltage-gated sodium channels in peripheral nerves conduct nociceptive signals from nerve endings to the spinal cord. Mutations in voltage-gated sodium channel NaV1.7 are responsible for a number of severe inherited pain syndromes, including inherited erythromelalgia (IEM). Here, we describe the negative shifts in the voltage dependence of activation in the bacterial sodium channel NaVAb as a result of the incorporation of four different IEM mutations in the voltage sensor, which recapitulate the gain-of-function effects observed with these mutations in human NaV1...

We show here that hyperpolarization-activated current (Ih ) unexpectedly acts to inhibit the activity of dorsal root ganglion (DRG) neurons expressing WT Nav1.7, the largest inward current and primary driver of DRG neuronal firing, and hyperexcitable DRG neurons expressing a gain-of-function Nav1.7 mutation that causes inherited erythromelalgia (IEM), a human genetic model of neuropathic pain. In this study we created a kinetic model of Ih and used it, in combination with dynamic-clamp, to study Ih function in DRG neurons...

Hyperexcitability in sensory neurons is known to underlie many of the maladaptive changes associated with persistent pain. Chemogenetics has shown promise as a means to suppress such excitability, yet chemogenetic approaches suitable for human applications are needed. PSAM4 -GlyR is a modular system based on the human α7 nicotinic acetylcholine and glycine receptors, which responds to inert chemical ligands and the clinically approved drug varenicline. Here, we demonstrated the efficacy of this channel in silencing both mouse and human sensory neurons by the activation of large shunting conductances after agonist administration...

No abstract text is available yet for this article.

Erythromelalgia (EM), is a familial pain syndrome characterized by episodic "burning" pain, warmth, and erythema. EM is caused by monoallelic variants in SCN9A, which encodes the voltage-gated sodium channel (NaV) NaV1.7. Over 25 different SCN9A mutations attributed to EM have been described to date, all identified in the SCN9A transcript utilizing exon 6 N. Here we report a novel SCN9A missense variant identified in seven related individuals with stereotypic episodes of bilateral lower limb pain presenting in childhood...

BACKGROUND: Mexiletine, a class IB antiarrhythmic, is a structural analog of lidocaine. Our knowledge of mexiletine overdose is based on lidocaine overdose reports. Only a few cases of mexiletine overdose have been reported, including fatal overdoses. Mexiletine toxicity primarily affects the central nervous, cardiovascular, and gastrointestinal systems. CASE: A 16-year-old female was brought to our hospital by ambulance after taking an unknown dose of mexiletine in a suicide attempt...

Erythromelalgia is a descriptive term for severe burning pain and erythema in the distal extremities relieved by cold and exacerbated by heat. Pediatric case series to date are relatively small. We extracted and analyzed medical record data for 42 pediatric patients to describe clinical characteristics, associated conditions, and responses to treatments. Informed consent was obtained according to an IRB-approved protocol that included gene discovery. Three patients had confirmed Nav1.7 sodium channelopathies, with six additional patients under investigation with novel gene candidates...

Polycythemia vera is a Philadelphia chromosome-negative myeloproliferative neoplasm that results in increased myeloproliferation. It is a debilitating disease characterized by the overproduction of red blood cells, but it also can result in increased white blood cells and platelets. Patients experience a shortened overall survival due to an increased risk of thrombotic events, including stroke, myocardial infarction, pulmonary embolism, and deep vein thrombosis. Current treatment strategies in clinical practice are driven by mitigating the risk of these thrombotic events by reducing patients' hematocrit...

INTRODUCTION: Primary erythromelalgia (EM) is a rare clinical syndrome characterized by recurrent erythema, burning pain and warmth of the extremities. The symptoms greatly compromise the patients' quality of life leading to severe disability. SCN9A mutations can be the cause of the disease. Dermatologists are often the specialists these patients turn to for assistance. OBJECTIVES: To describe the demographic and clinical characteristics of patients with primary EM, to assess the presence and mutation types in the SCN9A gene, to evaluate the effectiveness of several therapeutic approaches, and to propose a diagnostic algorithm with therapeutic implications...