Ocay DD, Graziano Maloney M, D'Souza G, Brownstein CA, Clinch J , et al.
Pediatric research •
Erythromelalgia is a rare, chronic pain disorder characterized by the triad of intense burning sensation, warmth, and redness, primarily involving the hands and feet, and usually alleviated by cold and worsened by heat. The objective of this scoping review was to: 1) map the existing literature on erythromelalgia in youth, 2) identify knowledge gaps, and 3) inform directions for future research in pediatric erythromelalgia. One hundred and sixty-seven studies reporting 411 cases of childhood-onset erythromelalgia were identified. Variability was found in reporting of clinical symptoms, the clinical presentations and diagnostic criteria used for classification of erythromelagia, the clinical assessments and investigations performed, and the types of interventions and management plans utilised. While factors to aid early recognition and optimize management have been identified, there are also significant gaps for future research to address. Ongoing efforts to develop a multicenter registry of pediatric erythromelalgia cases, with standardized data collection and reporting, will be beneficial to establish consensus recommendations for the diagnosis and management of pediatric erythromelalgia. IMPACT: This scoping review maps the existing literature on pediatric erythromelalgia. Variability was found in reporting of clinical symptoms, the clinical presentations and diagnostic criteria used for classification of erythromelagia, the clinical assessments and investigations performed, and the types of interventions and management plans utilised. The development of an international registry would immensely benefit multidisciplinary experts involved in the care of pediatric erythromelalgia and those with lived experience.
Ocay DD, Halpin M, Ford E, Keighley K, Keighley N , et al.
Children (Basel, Switzerland) •
: Erythromelalgia is a rare condition characterized by burning pain, redness, and warmth primarily in the extremities, usually worsened by heat and alleviated by cold. The objective of this study was to identify the top 10 priorities in pediatric erythromelalgia from multiple perspectives, including clinicians, people with lived experience of childhood-onset erythromelalgia, and their family members. : A modified James Lind Alliance Priority-Setting Process was conducted. The top priorities were identified through four phases: (1) an international online survey to gather priorities, (2) data processing, (3) an interim prioritization online survey, and (4) a virtual workshop to set the final priorities. : In phase 1, 185 potential priorities were submitted by 74 respondents (53% patients, 24% family members, and 23% clinicians) that were developed into 68 unique research questions (phase 2). In phase 3, of the 68 questions, 50 were rated for importance by 58 participants (38% patients, 36% family members, and 26% clinicians), reducing the list to 25 questions. In phase 4, the top 10 was reached through consensus by 12 participants (33% patients, 25% family members, and 42% clinicians) across Canada, South Africa, the United States of America, and the United Kingdom. : The final priorities focused on the treatment of erythromelalgia, understanding underlying mechanisms, the association of erythromelalgia with various body systems, and generating awareness. This list is the first international patient-centered research agenda for childhood-onset erythromelalgia and a call to action from key partners to improve future research and care.
Ma JE, Lee JUJ, Sartori-Valinotti JC, Rooke TW, Sandroni P , et al.
Mayo Clinic proceedings •
Erythromelalgia (EM) is a rare disorder characterized by episodic, burning pain associated with erythema and warmth of the extremities. The feet and hands are most commonly affected. The pain can be so severe that patients may engage in behaviors, sometimes extreme, to cool the affected areas and change their lifestyle to avoid precipitating factors, such as exercise and increased ambient heat. A literature search was performed with PubMed and MEDLINE with the search term erythromelalgia. Inclusion criteria were studies on EM published after 1985 until January 1, 2022, in the English language and studies that provided information on medical treatment of EM. Studies were excluded if they were duplicates or did not include treatment data. No guidelines exist for the treatment of this complex disorder. Lifestyle modifications and pharmacologic treatments (topical and systemic) are discussed in this article, which provides a comprehensive review of published medical management options for erythromelalgia and a proposed approach to management.
Pain practice : the official journal of World Institute of Pain •
Erythromelalgia is a rare neurovascular disorder characterized by erythema, warmth, and episodic burning pain, often felt in the face, hands, and feet. Symptoms are typically worse with heat, exercise, stress, and during the overnight hours. Management often requires a multidisciplinary approach, including pain trigger avoidance, cool water baths, and topical and oral neuropathic medications. The use of spinal cord stimulation has been described in multiple case reports with success reported out to 24Â months. To our knowledge, the use of dorsal root ganglion (DRG) stimulation for erythromelalgia-related pain has not been described. Herein, we present a case of erythromelalgia-related pain at the bilateral plantar surfaces of the feet, which was treated successfully with bilateral sacral S1 nerve root DRG stimulation.
Journal of the American Academy of Dermatology •
Corticosteroids (CS) may benefit certain patients with erythromelalgia. Our objective was to determine clinical predictors of corticosteroid-responsive erythromelalgia. Patients with erythromelalgia who received CS were identified and stratified into corticosteroid nonresponders (NRs), partial corticosteroid responders (PSRs), complete corticosteroid responders (CSRs), and steroid responders (SRs = PSRs + CSRs). In the study variable analysis, P < .05 was considered statistically significant. The median (interquartile range) age of the 31-patient cohort was 47 years (26-57 years), and 22 (71%) were female. Fourteen (45%) were NRs, 17 (55%) SRs, 8 (26%) PSRs, and 9 (29%) CSRs. A subacute temporal profile to disease zenith (<21 days) was described in 15 (48%) patients, of whom 13 (87%) were SRs (P = .003; odds ratio [OR] = 0.069 [95% confidence interval {CI}, 0.011-0.431]). Six (67%) CSRs reported a disease precipitant (eg, surgery, trauma, or infection; P = .007; OR = 12.667 [95% CI, 2-80.142]). SR patients received CS sooner than NR at 3 (3-12) versus 24 (17-45) months (P = .003). A high-dose CS trial (≥200 mg prednisone cumulatively) was administered to 17 (55%) patients, of whom 13 (76%) were SRs (P = .012; OR = 8.125 [95% CI, 1.612-40.752]). This was a retrospective case series. An infectious, traumatic, or surgical precipitant and subacute presentation may portend CR erythromelalgia. A transient "golden window" where CS intervention is useful may exist before irreversible nociceptive remodeling and central sensitization occurs.
Erythromelalgia is a clinical diagnosis based on intermittent warmth, erythema, and pain in the distal extremities. One problem facing physicians is how to objectively test for this disease. Given that other painful conditions of the distal extremities (ie, neuropathy related to human immunodeficiency virus, diabetes, or Fabry disease) can be evaluated with a skin biopsy to visualize pathologically decreased densities of the small nerve fibers that innervate the epidermis, one hypothesis is that erythromelalgia could similarly be associated with a loss of epidermal nerve fiber density (ENFD). To examine whether erythromelalgia is associated with a structural loss of small fibers using the ENFD technique and to compare this with functional studies of small nerve fibers. In a retrospective study of 52 consecutive patients with erythromelalgia who were seen between September 1, 2010, and September 22, 2015, patients were interviewed and examined and their conditions clinically diagnosed by a board-certified dermatologist at a large tertiary referral center, where ENFD testing became a routine part of evaluating erythromelalgia in 2010. Thus, all 52 consecutive patients were included solely based on their clinical diagnosis of erythromelalgia. For quantification of ENFD, observers were masked to all patient information except for name and clinic number. The hypothesis that patients with erythromelalgia would have decreased ENFD was formulated before data collection. Epidermal nerve fiber density, the primary outcome, is a measurement of the density of small nerve fibers within the epidermis. Secondary measures included functional small fiber evaluation, such as autonomic (heart rate, blood pressure, and sweat testing) and subjective testing of pain. In this cohort study, 52 consecutively seen patients were identified (female, 42 [80%]; median age, 44 years; age range, 13-82 years). Whereas only 5 of 52 patients (10%) had ENFD at or below the fifth percentile of healthy control individuals, most patients had functional abnormalities of these small fibers; 29 patients (60%) had abnormal sweat test results, 21 (42%) had abnormal pain thresholds, and 20 (38%) had abnormal blood pressure or heart rate control. Unlike other diseases of the small nerve fibers that cause acral pain syndromes, erythromelalgia is not characterized by loss of ENFD. However, most patients have impaired function of these small fibers. Physicians would benefit from performing functional rather than structural small fiber studies when evaluating erythromelalgia.
Many skin and skin-related diseases affect the sexes unequally, with attendant implications for public health and resource allocation. To evaluate better the incidence of skin and skin-related diseases affecting males vs. females, we reviewed published population-based epidemiology studies of skin disorders performed utilizing Rochester Epidemiology Project data. Females had a higher incidence of the following diseases: connective tissue diseases (scleroderma, morphea, dermatomyositis, primary Sjögren syndrome, systemic lupus erythematosus [not in all studies]), pityriasis rosea, herpes progenitalis, condyloma acuminatum, hidradenitis suppurativa, herpes zoster (except in children), erythromelalgia, venous stasis syndrome, and venous ulcers. Males had a higher incidence of psoriasis and psoriatic arthritis, basal cell carcinoma (exception, females aged ≤40 years), squamous cell carcinoma, and lentigo maligna. Incidence rates were equal in males and females for cutaneous malignant melanoma (exception, higher in females aged 18-39 years), lower-extremity cellulitis, cutaneous nontuberculous mycobacterial infection, Behçet disease, delusional infestation, alopecia areata, and bullous pemphigoid. Many of the population-based sex-specific incidence rates of skin and skin-related diseases derived from the Rochester Epidemiology Project are strikingly different from those estimated elsewhere. In general, females are more commonly affected by skin and skin-related diseases. The reasons for this imbalance remain to be determined and are likely multifactorial.
Klein CJ, Wu Y, Kilfoyle DH, Sandroni P, Davis MD , et al.
Journal of neurology, neurosurgery, and psychiatry •
Mutations in SCN9A have been reported in (1) congenital insensitivity to pain (CIP); (2) primary erythromelalgia; (3) paroxysmal extreme pain disorder; (4) febrile seizures and recently (5) small fibre sensory neuropathy. We sought to investigate for SCN9A mutations in a clinically well-characterised cohort of patients with CIP and erythromelalgia. We sequenced all exons of SCN9A in 19 clinically well-studied cases including 6 CIP and 13 erythromelalgia (9 with family history, 10 with small-fibre neuropathy). The identified variants were assessed in dbSNP135, 1K genome, NHLBI-Exome Sequencing Project (5400-exomes) databases, and 768 normal chromosomes. In erythromelalgia case 7, we identified a novel Q10>K mutation. In CIP case 6, we identified a novel, de novo splicing mutation (IVS8-2A>G); this splicing mutation compounded with a nonsense mutation (R523>X) and abolished SCN9A mRNA expression almost completely compared with his unaffected father. In CIP case 5, we found a variant (P610>T) previously considered causal for erythromelalgia, supporting recently raised doubt on its causal nature. We also found a splicing junction variant (IVS24-7delGTTT) in all 19 patients, this splicing variant was previously considered casual for CIP, but IVS24-7delGTTT was in fact the major allele in Caucasian populations. Two novel SCN9A mutations were identified, but frequently polymorphism variants are found which may provide susceptibility factors in pain modulation. CIP and erythromelalgia are defined as genetically heterogeneous, and some SCN9A variants previously considered causal may only be modifying factors.
Cook-Norris RH, Tollefson MM, Cruz-Inigo AE, Sandroni P, Davis MD , et al.
Journal of the American Academy of Dermatology •
Erythromelalgia has not been well characterized in the pediatric population. We sought to review our experience of erythromelalgia in the pediatric age group. We conducted a retrospective review of patients 18 years of age and younger with a diagnosis of erythromelalgia who were examined at Mayo Clinic in Rochester, MN, from 1970 to 2007. The records of 32 patients (girls, 22 [69%]) were evaluated. Mean age was 14.1 years (range, 5-18 years) and mean time to diagnosis was 5.2 years. Seven patients (22%) had a first-degree relative with erythromelalgia; 4 were from the same family. Physical activity was limited because of discomfort in 21 patients (66%) and school attendance was affected in 11 patients (34%). Noninvasive vascular studies, which compared temperature, laser Doppler flow, and transcutaneous oximetry in the toes, identified vascular abnormalities in 13 (93%) of 14 patients. Neurophysiologic studies with autonomic reflex screening (including quantitative sudomotor axon reflex test and thermoregulatory sweat testing) showed evidence of a small-fiber neuropathy involving the skin in 10 (59%) of 17 patients studied; there was no evidence of large-fiber neuropathy in 20 patients in whom electromyographic and nerve conduction studies were performed. Topical lidocaine was the most commonly prescribed treatment (44%). Fifteen patients were monitored for an average of 9.1 years (median, 5.0 years; range, 0.4-23.7 years). At last follow-up, 5 patients had stable disease, 4 showed improvement, two had resolution, one reported worsening of symptoms, and 3 had died (one suicide). Conclusions are limited because this was a retrospective chart review. Erythromelalgia in pediatric patients is associated with substantial morbidity and even death. The majority of cases are not inherited. Most patients studied have associated small-fiber neuropathy. The disease course is variable. A reliable and safe treatment has not been determined.
Erythromelalgia is a rare disorder characterized by the clinical syndrome of burning pain, warmth and redness of the limbs. Neurological abnormalities (both large- and small-fibre neuropathy) are common. There have been few published reports on the sensory status of patients with erythromelalgia. To investigate the results of quantitative sensation testing in erythromelalgia using computer-assisted sensory evaluation, including vibratory detection threshold, cool detection threshold and heat-pain threshold (HPT). Patients who underwent dermatological or neurological evaluation of suspected erythromelalgia at our institution and received a final diagnosis of erythromelalgia were identified from a master diagnosis index covering the period January 1994 to June 2008. A retrospective chart review was performed. Main outcome measures were sensory abnormalities (e.g. pain, burning sensation, tingling) in response to heat, cooling and vibration during computer-assisted sensory testing. In total, 41 patients with erythromelalgia were enrolled in the study and underwent computer-assisted sensory evaluation. Of these, 34 patients (82.9%) had abnormal results. The commonest abnormality was isolated HPT: 11 patients (26.8%) had heat hypoalgesia and 18 (43.9%) had heat hyperalgesia, whereas only 2 (4.9%) of the healthy control patients had hyperalgesia on testing. Multiple sensory modalities were found to be abnormal in patients with erythromelalgia, with the commonest clinical abnormality being isolated heat-pain abnormality. These findings lend support to the notion that neuropathy underlies the clinical diagnosis of erythromelalgia. Future studies will explore the nature of the relationship between these sensory abnormalities and the clinical features of erythromelalgia.
Skeik N, Rooke TW, Davis MD, Davis DM, Kalsi H , et al.
Vascular medicine (London, England) •
Erythromelalgia is a rare clinical syndrome characterized by intermittent heat, redness, swelling and pain more commonly affecting the lower extremities. Symptoms are mostly aggravated by warmth and are eased by a cold temperature. In some cases, symptoms can be very severe and disabling. Erythromelalgia can be classified as either familial or sporadic, with the familial form inherited in an autosomal dominant manner. Recently, there has been a lot of progress in studying Na(v)1.7 sodium channels (expressed mostly in the sympathetic and nociceptive small-diameter sensory neurons of the dorsal root ganglion) and different mutations affecting the encoding SCN9A gene that leads to channelopathies responsible for some disorders, including primary erythromelalgia. We present a severe case of progressive primary erythromelalgia caused by a new de novo heterozygous missense mutation (c.2623C>G) of the SCN9A gene which substitutes glutamine 875 by glutamic acid (p.Q875E). To our knowledge, this mutation has not been previously reported in the literature. We also provided a short literature review about erythromelalgia and Na(v) sodium channelopathies.
To describe the response in patients with erythromelalgia to the pain rehabilitation program at Mayo Clinic, Rochester, Minnesota. Retrospective case series. Comprehensive Pain Rehabilitation Center at a tertiary referral medical center. Patients Eight patients with erythromelalgia admitted to the pain rehabilitation program from January 1, 2002, through June 30, 2007. The Multidimensional Pain Inventory, the 36-Item Short Form Health Survey, the Pain Catastrophizing Scale, and the Center for Epidemiologic Studies Depression Scale were administered at admission and dismissal from the program. Mean differences in scores were compared using 2-sided paired t tests. Scores for the life interference, life control, and general activity subscales of the Multidimensional Pain Inventory showed significant improvement from admission to dismissal (all P < .05). Similarly, the scores of the Pain Catastrophizing Scale, the Center for Epidemiologic Studies Depression Scale, and the physical functioning and emotional role limitation subscales of the 36-Item Short Form Health Survey were significantly improved after intervention (all P < .01). Conclusion The results of our study indicate that pain rehabilitation is a useful method for managing pain-related impairment in physical and emotional functioning in patients with erythromelalgia.
Davis MD, Weenig RH, Genebriera J, Wendelschafer-Crabb G, Kennedy WR , et al.
Journal of the American Academy of Dermatology •
The histopathology of primary erythromelalgia has been poorly characterized. A total of 33 skin biopsy specimens from 29 patients with a diagnosis of primary erythromelalgia were re-examined. Histopathologic findings were nonspecific. Vascular thrombi were not identified. A relative decrease in small nerve fiber density was noted in specimens from 13 of 16 patients.
To examine the results of thermoregulatory sweat testing in patients with erythromelalgia and to compare them with the results of other neurophysiologic tests of small-fiber nerve function. Retrospective study. Tertiary referral center. Thirty-two consecutive patients with erythromelalgia who had thermoregulatory sweat testing in addition to vascular and nerve testing. The following information was abstracted for each patient: demographics, clinical presentation, and results of thermoregulatory sweat testing, vascular (noninvasive) testing, and nerve testing (electromyography and autonomic reflex screen, including quantitative sudomotor axon reflex test). Results of thermoregulatory sweat testing to evaluate small-fiber neuropathy, compared with other tools used to estimate small-fiber neuropathy. Thermoregulatory sweat testing results were abnormal in 28 (88%) of 32 patients, and quantitative sudomotor axon reflex test results were abnormal in 22 patients (69%). Abnormalities noted on thermoregulatory sweat testing varied from local hypohidrosis or anhidrosis to global anhidrosis. Global or almost-global anhidrosis was present in 8 patients (25%); in 19 patients (59%) the anhidrosis was distal, and 1 other patient (3%) had a less specific pattern of anhidrosis (multifocal or regional). The area of anhidrosis generally corresponded to the area that was symptomatic of the erythromelalgia. Small-fiber neuropathy is prevalent in most patients with erythromelalgia. Thermoregulatory sweat testing is a sensitive and useful marker of small-fiber neuropathy in these patients.
Current treatment options in cardiovascular medicine •
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.
The natural history of polycythemia vera (PV) includes an increased lifetime risk of thrombohemorrhagic complications and disease transformation into myelofibrosis with myeloid metaplasia and acute myeloid leukemia. The latter is the primary reason for the shortening of survival that becomes significant after the first decade of disease. Historic nonrandomized studies have suggested that aggressive phlebotomy improves survival in PV. However, prospective randomized studies have failed to demonstrate a better treatment than phlebotomy alone, in terms of survival. However, the addition of cytoreductive therapy to phlebotomy in high-risk patients with PV may reduce the risk of recurrent thrombosis. Other disease features of PV include aquagenic pruritus and microvascular disturbances such as erythromelalgia. This review outlines a practical approach to diagnosis, in addition to treatment of life-threatening and non-life-threatening complications of PV.
Current treatment options in cardiovascular medicine •
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.
To describe the demographics, presentation, and outcome in patients with erythromelalgia--a rare and poorly understood clinical syndrome defined by the triad of red, hot, painful extremities. Retrospective medical record review with follow-up by survey questionnaire. Large tertiary care medical center. Patients with erythromelalgia examined at the Mayo Clinic, Rochester, Minn, between 1970 and 1994. The medical records of 168 patients were analyzed. Follow-up data, which consisted of answers to 2 survey questionnaires or the most recent information in the medical record from patients still alive and death certificates or reports of death for those deceased patients, were obtained for all but 13 patients. Survival, morbidity, and quality of life. All patients were white; 122 (72.6%) were female, and 46 (27.4%) were male. At presentation, the patients' mean age was 55.8 years (age range, 5-91 years). Symptoms had been present since childhood in 7 patients (4.2%). Six patients (3.6%) had a first-degree relative with erythromelalgia. Symptoms were intermittent in 163 patients (97.0%) and constant in 5 (3.0%). Symptoms predominantly involved feet (148 patients [88.1%]) and hands (43 patients [25.6%]). Kaplan-Meier survival curves revealed a significant decrease in survival compared with that expected in persons of similar age and of the same sex (P<.001). After a mean follow-up of 8.7 years (range, 1.3-20 years), 30 patients (31.9%) reported worsening of, 25 (26.6%) no change in, 29 (30.9%) improvement in, and 10 (10.6%) complete resolution of the symptoms. On a standard health status questionnaire, scores for all but one of the health domains were significantly diminished in comparison with those in the US general population. Erythromelalgia is a syndrome with significantly increased mortality and morbidity compared with the US general population.
