Histopathology of erythema nodosum

The histopathology of erythema nodosum is discussed with reference to the literature and of 19 cases of our clinic. There is a significant vascular involvement especially of the subcutaneous tissue. The veins and arteries are equally affected. The histological picture consists not only of an acute inflammatory process in the subcutaneous tissue, but also of inflammatory cells which area see to a lesser extent in the dermis. In many cases the typical small granulomatous foci of MIESCHER which are considered to be pathognomonic for erythema nodosum do not develop. In the cases which we examined we were not always able to tell from the histological picture how long the erythema nodosum had been present. Multinucleated giant cells which are often found in the septal connective tissue are seen even in relatively acute cases.     

结节性红斑的病因学研究进展

结节性红斑是一种脂膜炎,常发生于双侧胫前,以红斑、痛性皮下结节为主要表现.青年女性好发.组织学表现为间隔性脂膜炎,伴多种炎症细胞浸润.确切的发病机制尚不明确,目前认为可能是一种迟发超敏反应,也有学者认为,是免疫复合物沉积在脂肪间隔的小静脉所致,引起嗜中性脂膜炎.病因复杂,与感染、系统性疾病、药物、激素水平、恶性肿瘤等因素相关.由于地区差异,病因可能有所不同.     

Leucocyte activation in erythema nodosum

As a neutrophilic vascular reaction of small vessels in the subcutaneous tissue and a neutrophilic inflammatory infiltrate are common histopathological features found in initial erythema nodosum (EN) lesions, we asked the question whether activated polymorphonuclear neutrophils (PMN) might play a role in the pathogenesis of EN. We analysed the production of reactive oxygen intermediates (ROI) as a marker for activated neutrophils in the peripheral blood of patients suffering from EN (n = 10) and healthy volunteers (n = 10). FACS analysis of dihydrorhodamine 123-stained PMN was used to detect ROI production due to respiratory burst activity. Patients suffering from EN had a fourfold higher percentage of preactivated ('primed') ROI-producing PMN compared with healthy volunteers. Activation of PMN with formylated methionyl-leucyl-phenylalanine and phorbol 12-myristate 13-acetate led to an increase of ROI production per cell but had no influence on the percentage of activated cells. The percentage of ROI-producing cells in patients with EN correlated with the clinical severity. From these data, we conclude that ROI might play a role in the pathogenesis of EN. ROI might exert their effects by oxidative tissue damage and by promoting tissue inflammation.     

Necrotic erythema nodosum leprosum

A 30 year-old farmer presented himself with mild degree fever, joint pain and multiple ulcers of 15 days' duration. Ulcers were multiple, well-defined, irregular in shape with necrotic base and elevated, sloppy margins over anus, forearms, wrists, buttocks, lower half of thighs and shins. A few of the ulcers were covered with black-coloured scab. They were tender and with serosanguinous discharge. Black atrophic scars and ill-defined, irregular, brown black-pigmented macules of various sizes were present over thighs and legs. Excision biopsy of the ulcer showed features of erythema nodosum leprosum. The patient was treated with systemic corticosteroids.     

Necrotic erythema nodosum leprosum

A 32-year-old fisherman suffering from lepromatous leprosy presented with fever, joint pains, bullous lesions, and multiple well-defined ulcers on the extremities and back of 10-days duration. The bullae ruptured to form ulcers of varying sizes with well-defined margins and necrotic bases. A few of the ulcers had black crusts resembling eschars. An immunofluorescence study ruled out autoimmune bullous disease. Histopathology of a lesion showed features of erythema nodosum leprosum.     

Histopathologic spectrum of erythema nodosum

Erythema nodosum (EN) is the most common panniculitis and histologically represents the prototype of a septal panniculitis. However, the histologic findings can be quite variable. We describe four patients with EN who each underwent two consecutive biopsies. In each case, the first biopsy showed histopathologic features that fall outside the usual spectrum of disease. Two cases showed predominantly neutrophilic infiltrates with focal suppuration as well as vasculitis of medium-sized arteries. The areas of suppuration were more extensive in the first case prompting special stains for microorganisms that were all negative. The third case demonstrated a lobular panniculitis with a predominantly lymphohistiocytic infiltrate. Special stains were negative in this case as well. The fourth case revealed vasculitis of a medium sized artery, small vessel vasculitis, and a mixed septal and lobular panniculitis with a polyclonal population of atypical lymphocytes. In all patients, the clinical course and the subsequent biopsy were classic for EN. We conclude that lobular neutrophilic panniculitis with suppuration, small vessel vasculitis, and even medium vessel arteritis may rarely occur in EN. There are few clues in these unusual cases that allow for a specific diagnosis from the start, and often, a second biopsy is required.     

麻风结节性红斑的治疗

麻风结节性红斑（ENL）,又称2型麻风反应,是一种免疫介导的急性或亚急性并发症,多发生在瘤型（LL）或界线类偏瘤型（BL）麻风,ENL发生率各地报告差异很大,在LL中发生率为11.1% ~ 26%,平均15.4%,在BL中为2.7% ~ 5.1%,平均4.1%［1］。表现为炎症性皮肤结节和多个器官系统受累,病程常比较迁延,也容易复发,可以导致各种残疾的发生,给患者的生活质量带来较大的影响。ENL基本发病机制是免疫复合物的产生和沉积以及补体激活,但是也有T细胞和巨噬细胞功能异常导致肿瘤坏死因子α（TNF-α）水平升高的证据［2］……     

Non-Hodgkin's lymphoma simulating erythema nodosum

Two cases of malignant lymphoma whose initial clinical presentations simulated unilateral erythema nodosum on the leg are reported. In one case, the first diagnosis was in error, while, in the other, the diagnosis was confirmed by the histology. The patients later developed widespread malignant lymphoma. An increased awareness of this symptomology in patients with malignant lymphoma may lead to earlier diagnosis and appropriate therapy.