Acute secondary erythermalgia and hypertension in children. Erythermalgia Multidisciplinary Study Group

Clinical Challenges in Primary Erythromelalgia: a Real-Life Experience from a Single Center and a Diagnostic-Therapeutic Flow-Chart Proposal

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.

METHODS

A monocentric retrospective study using the database of patients with a discharge diagnosis of primary EM of our Center. Demographic, clinical, instrumental and laboratory data of patients were reviewed.

RESULTS

Eleven female patients (age range 16 to 57) were selected. All patients were affected in both the lower and upper extremities. Follow-up ranged from 2 to 9 years. Four patients had four different heterozygous variants of the SCN9A gene. Two patients, although genetically negative, had a suggestive family history. A variety of medications were tried in all our patients to alleviate symptoms, but their efficacy was variable, partial and/or transitory. The most effective therapies were antihistamines, venlafaxine, and mexiletine.

CONCLUSIONS

The diagnosis and treatment of EM remain challenging. Patients with this condition display a wide spectrum of clinical manifestations and severity, as well as a paucity of resources and structures to support them. Mutations in the SCN9A gene are not always detected.

Pediatric Erythromelalgia and SCN9A Mutations: Systematic Review and Single-Center Case Series

OBJECTIVES

To evaluate the clinical features of erythromelalgia in childhood associated with gain-of-function SCN9A mutations that increase activity of the Na_v1.7 voltage-gated sodium channel, we conducted a systematic review of pediatric presentations of erythromelalgia related to SCN9A mutations, and compared pediatric clinical presentations of symptomatic erythromelalgia, with or without SCN9A mutations.

STUDY DESIGN

PubMed, Embase, and PsycINFO Databases were searched for reports of inherited erythromelalgia in childhood. Clinical features, management, and genotype were extracted. Case notes of pediatric patients with erythromelalgia from the Great Ormond Street Hospital Pain Service were reviewed for clinical features, patient-reported outcomes, and treatments. Children aged over 10 years were recruited for quantitative sensory testing.

RESULTS

Twenty-eight publications described erythromelalgia associated with 15 different SCN9A gene variants in 25 children. Pain was severe and often refractory to multiple treatments, including nonspecific sodium channel blockers. Skin damage or other complications of cold immersion for symptomatic relief were common (60%). SCN9A mutations resulting in greater hyperpolarizing shifts in Na_v1.7 sodium channels correlated with symptom onset at younger ages (P = .016). Variability in reporting, and potential publication bias toward severe cases, limit any estimations of overall prevalence. In our case series, symptoms were similar but comorbidities were more common in children with SCN9A mutations. Quantitative sensory testing revealed marked dynamic warm allodynia.

CONCLUSIONS

Inherited erythromelalgia in children is associated with difficult-to-manage pain and significant morbidity. Standardized reporting of outcome and management in larger series will strengthen identification of genotype-phenotype relationships. More effective long-term therapies are a significant unmet clinical need.

Erythema and burning pain in the vulva: a possible phenotype of erythromelalgia

We report a case of burning vulvar pain accompanied by erythema responding to an oral combination of a benzodiazepine and a beta blocker. The positive response to two medication classes used in the treatment of erythromelalgia supports the possibility of a localized manifestation of this disorder in the genital region.

Erythromelalgia

No treatment is consistently effective in the management of patients with erythromelalgia. There is a dearth of adequate studies examining the response of erythromelalgia to treatment. Most recommendations are suggested based on case reports, small case series, and anecdotal reports. The management of erythromelalgia is difficult and frequently involves a multidisciplinary approach. An approach to management of individuals with erythromelalgia includes patient education, learning to avoid episodes, relieving discomfort of the episodes, controlling secondary and underlying factors, and use of drugs used to control erythromelalgia.

Platelet-mediated microvascular inflammation and thrombosis in thrombocythemia vera: a distinct aspirin-responsive arterial thrombophilia, which transforms into a bleeding diathesis at increasing platelet counts

Erythromelalgia is the main, pathognomonic and presenting symptom in patients with essential thrombocythemia and thrombocythemia associated with polycythemia vera. Complete relief from erythromelalgic and acrocyanotic pain is obtained with the cyclooxygenase inhibitors aspirin and indomethacin, but not with sodiumsalicylate, dipyridamol, sulfinpyrozone and ticlopedine. Thus, cyclooxygenase metabolites are necessary for erythromelalgia to develop. Local platelet consumption in erythromelalgic areas became evident by the demonstration of arteriolar fibromuscular intimal proliferation and occlusions by platelet-rich thrombi in skin biopsies, by the findings of shortened platelet survival times, significant higher levels of platelet activation markers beta-thromboglobulin, thrombomoduline and increased urinary thromboxane B2 excretion in thrombocythemia patients suffering from erythromelalgia. Aspirin treatment of erythromelalgia in thrombocythemia patients resulted in the disappearance of the erythromelalgic, thrombotic signs and symptoms, correction of the shortened platelet survival times, and a significant reduction of the increased levels of beta-TG, PF4, TM and urinary TxB2 excretion to normal. Erythromelalgia is frequently preceded or followed by atypical transient neurologic, ocular or coronary ischemic symptoms, which specifically respond to low-dose aspirin or reduction of platelet counts to normal. The broad spectrum of acropareshesias, erythromelalgia and acrocyanotic ischemia together with the episodic and transient atypical TIAs and ocular or coronary ischemic symptoms are caused by spontaneous activation and aggregation of hypersensitive platelets in the end-arterial microvasculature involving the peripheral, cerebral and coronary circulation of thrombocythemia patients. These microvascular circulation ischemic disturbances in thrombocythemia vera already occur at platelet counts in excess of 400 x 10(9) l(-1). Low-dose aspirin is highly effective and safe in the cure and prevention of thrombotic and ischemic events and does not elicit bleedings at platelet counts below 1000 x 10(9) l(-1). Spontaneous hemorrhages usually occur at very high platelet counts far in excess of 1000 x 10(9) l(-1) (HT) due to an acquired von Willebrand factor deficiency at increasing platelet counts. At platelet counts between 1000 and 2000 x 10(9) l(-1), thrombosis and bleeding (ETT and HT) frequently occur in sequence or paradoxically and low-dose aspirin does prevent thrombotic complications but aggravates or may elicit bleeding symptoms. Reduction of the platelet count to below 1000 x 10(9) l(-1) by platelet lowering agents usually results in the disappearance of the bleeding tendency and improvement of the von Willebrand syndrome, but the thrombotic tendency persists as long as platelet counts are above the upper limit of normal.

Erythromelalgia

No treatment is consistently effective in the management of patients with erythromelalgia. There is a dearth of adequate studies examining the response of erythromelalgia to therapy. Most recommendations are suggested based on case reports, small case series, and anecdotal reports. The management of erythromelalgia is difficult and frequently involves a multidisciplinary approach. An approach to management of individuals with erythromelalgia includes patient education, learning to avoid episodes relieving discomfort of the episodes, controlling secondary and underlying factors, and use of drugs used to control erythromelalgia.

Acute, severe self-limiting dysautonomia and hypertensive encephalopathy

We describe two unrelated children with almost identical clinical illnesses comprising of severe, burning dysesthesia, allodynia, hypertensive encephalopathy, and laboratory evidence of both sympathetic and parasympathetic autonomic disturbance after a nonspecific viral illness. No underlying etiology was identified. Both patients displayed complete resolution of their clinical and radiologic findings after a number of months, and there was no recurrence over a follow-up period of 17 months to 4 years. Treatment of the patients' dysesthesias proved difficult, requiring multiple analgesics and intensive physiotherapy. We speculate that their illnesses may represent a pure autonomic variant of Guillain-Barré syndrome.

Unexpected healing of cutaneous ulcers in a short child

A boy aged 10 years was referred to the Paediatric Department of Milan University Hospital, Milan, Italy, with a long history of pain in the lower limbs, alleviated only by exposure to cold. His legs were swollen, with multiple cutaneous ulcers. He had severe painful crises, and was totally incapacitated. After the diagnosis of erythermalgia was made, numerous treatments were tried, but none were successful. After finding growth hormone (GH) deficiency, we started treatment with recombinant GH. He had immediate relief of pain and complete healing of ulcers. We postulate that the healing of the ulcers can be attributed to the GH-promoting effect on dermal connective tissue.

Erythromelalgia: new theories and new therapies

Erythromelalgia is a rare condition that has remained an enigma diagnostically and therapeutically for decades. It has been assumed that erythromelalgia, which is characterized by hot, red, intensely painful feet or hands, may be the opposite of Raynaud's phenomenon. However, new research suggests that these two disorders are more similar than dissimilar. Erythromelalgia usually follows a chronic, sometimes progressive and disabling course. New evidence suggests that this may not be a disease entity at all, but a syndrome of dysfunctional vascular dynamics; recent studies demonstrate that this dysfunction is reversible in some patients. This review article presents the latest theories and successful treatments for erythromelalgia, and data from a survey of members of The Erythromelalgia Association, which was formed to provide information about erythromelalgia to doctors and patients.

Nitroprusside treatment of erythromelalgia in an adolescent female

OBJECTIVE

To report a case of erythromelalgia in an adolescent patient successfully treated with nitroprusside.

CASE SUMMARY

A 15-year-old girl with erythromelalgia resistant to aspirin therapy received an infusion of nitroprusside. The response of the erythromelalgia to nitroprusside was dramatic, with complete pain resolution within 17 hours after the start of therapy. No relapse of erythromelalgia was seen when nitroprusside was discontinued and the patient remained well after 6 months.

DISCUSSION

This case adds to existing literature substantiating the benefit of nitroprusside for the treatment of erythromelalgia in pediatric patients. Erythromelalgia in children may represent a different disease entity than that seen in adults, which is commonly responsive to aspirin therapy. The pathogenesis of erythromelalgia is unclear and precludes formulating a proposed mechanism by which nitroprusside has benefit in children.

CONCLUSIONS

Nitroprusside is valuable for erythromelalgia resistant to aspirin therapy in pediatric patients. Because of unanswered questions regarding the disease, aspirin remains the agent of first choice in all patients with this rare disease.