Primary erythrocytic (PEM) is a rare autosomal dominant single gene disease. Most of the changes of gene loci can be found by whole exon gene sequencing, and the clinical symptoms and patient survival can be improved by specific site-to-site drug treatment. The other manifestations of this patient population are not remarkable. After the application of common drugs, the toxicity and side effects can be limiting. In addition to other common clinical manifestations, we found that the only unique manifestation of this patient was hypertensive crisis. Following multidisciplinary diagnosis and treatment (MDT), we decided to first control hypertension to alleviate the acute and critical patients. However, after controlling the hypertensive crisis, we unexpectedly found that the clinical symptoms of the patients had been significantly improved. Therefore, we concluded that the use of antihypertensive drugs can treat erythematous limb pain with the clinical manifestation of hypertensive crisis. Here, we describe a typical PEM disease, primary clinical features, diagnosis and treatment. Medical records of an 8-year-old boy with PEM were analyzed retrospectively, which included clinical characteristics, follow-up information, and SCN9A (Sodium Voltage-Gated Channel Alpha Subunit 9) gene analysis. The 8-year-old boy had complained of abnormal paresthesia in his feet and ankles with burning sensation and pain for 2 years. The skin of both lower legs was red and underwent ichthyosis and lichenification. Genetic analysis confirmed the existence of a SCN9A gene mutation. The symptoms were gradually improved by treating with intravenous drip and oral administration of nitroglycerin to slow his heart rhythm. Primary erythrocytic is characterized by skin ulceration, redness, elevated temperature, and severe burning pain primarily in both lower extremities. PEM can be diagnosed by genetic analysis. As this case demonstrates, treating with nitroglycerin as the drug of choice to control the hypertensive crisis significantly improved the symptoms of PEM and hypertension in this patient.
Erythermalgia, a rare painful disorder, is characterized by recurrent pain attacking, warmth, and erythema that mainly involves the distal extremities. Red ear syndrome shares similar clinical features of erythermalgia afflicting the external ear with unilateral/bilateral distribution. The treatments of both diseases are still difficult without controlled therapeutics available up to date. A 12-year-old boy was referred because of 3 years of recurrent attacking of painful erythema and warmth that involved the ears alone, the episodes occurred several times daily with duration of dozens of minutes to hours for each flare. The symptoms could be relieved by cold water and triggered by heat stimuli as well as exciting and movement, and showed mild response to gabapentin, celecoxib, and topical lidocaine compounds in combination, but moderate to blocking injection of botulinum toxin to nervus auricularis magnus. However, systemic itraconazole 200 mg daily resulted in an excellent response after 5-week treatment, leading to milder erythema, warmth and burning sensation, shorter duration, and fewer relapses. The treatment continued for 6 months and then itraconazole was decreased to 100 mg daily for another 6 months until it was stopped, with maintenance of good conditions. In 3 months of follow-up after the treatment ceased, the patient had only 7 to 8 attacks over 10 days presenting as tolerable erythema that lasted for less than 10 min and relieved spontaneously, with absence of warmth and no need of treatment. We considered the patient to be a variant of erythermalgia rather than a red ear syndrome. The results showed that erythermalgia might involve the ears alone and itraconazole might be a potential agent for its treatment.
Dozens of epidemic erythromelalgia (EM) outbreaks have been reported in China since the mid-twentieth century, and the most recent happened in Foshan City, Guangdong Province early 2014. This study compared the daily case counts of this recent epidemic EM outbreak from February 11 to March 3 with Baidu search data for the same period. After keyword selection, filtering and composition, the most correlated lag of the EM Search Index was used for comparison and linear regression model development. This study also explored the spatial distribution of epidemic EM in China during this period based on EM Search Index. The EM Search Index at lag 2 was most significantly associated with daily case counts in Foshan (ρ = 0.863, P < 0.001). It captured an upward trend in the outbreak about one week ahead of official report and the linear regression analysis indicated that every 1.071 increase in the EM Search Index reflected a rise of 1 EM cases 2 days earlier. The spatial analysis found that the number of EM Search Indexes increased in the middle of Guangdong Province and South China during the outbreak period. The EM Search Index may be a good early indicator of an epidemic EM outbreak.
Erythermalgia is a rare cutaneous disorder characterized by attacking of erythema, pain and increased temperature, which primarily involves the extremities and may infrequently extend to the neck, face, ears and even the scrotum. We reported an 18-year-old woman who presented with 3 years history of sole involvement of attacking erythema, pain and warmth over her face and ears without any other associations. The frequency and severity of the flares progressed gradually during the course. Cutaneous examination revealed erythema, increased temperature and tenderness on the face and ears during the flare. The symptoms could be relieved rapidly by cooling. Dermatoscope showed that vessels inside the erythema were more dilated during the episode than after application of ice. The lesion is considered a rare variant of erythermalgia with sole involvement of face and ears. The symptoms had mild response to oral antihistamines, topical steroids and tacrolimus, but had excellent response to the combinative therapy of aspirin and paroxetins.
Erythromelalgia is a rare clinical syndrome characterized by episodic attacks of burning pain, erythema, and increased temperature, primarily affecting the extremities, and in rare instances, involving the ear, face, neck, and the scrotum. The dermatoscopic features of erythromelalgia in a case with solely facial involvement have never been described previously. We describe a 14-year-old female who presented with erythema, burning sensation, and warmth on her face only, which mimic the features of erythromelalgia. Physical examination showed higher temperature on the involved cheeks than on axillas during the episode, while the temperature on both areas was the same between episodes. Dermatoscope showed more dilated vessels inside the erythema during the episodes than between the episodes. The symptoms had excellent response to the combination treatment of gabapentin, indomethacin, and topical lidocaine compounds. The present case is considered to be a variant of erythromelalgia. Its erythema may be resulted from the dilated vessels. Combination of modalities may provide effective management for erythromelalgia. "Erythermalgia" may be better than "erythromelalgia" to describe such conditions.
We report an 11-year-old boy with localized secondary erythromelalgia on his left medial thigh. The episodes responded well to indomethacin and prednisone but recurred after the medications were stopped. The disease was stable after being treated for 5 months.
