背景:色素性紫癜性皮肤病(PPD)的特征是斑点,紫癜性斑疹,双侧下肢色素沉着。它运行一个慢性和复发的过程。病理生理学知之甚少,但它被认为是一种免疫复杂疾病或毛细血管炎。这项研究旨在确定临床和组织病理学证实的PPD患者中直接免疫荧光(DIF)阳性发现的发生率和模式。还分析了DIF沉积类型与临床特征之间的关联。
方法:本研究包括在2002年1月至2021年12月期间在三级医疗中心与皮肤病理学和免疫荧光诊断中心进行DIF研究的临床和组织病理学PPD诊断患者。年龄数据,性别,疾病持续时间,合并症,和药物摄入量是从医疗记录中收集的。
结果:有65例患者符合纳入标准。其中,58(89%)至少有一个阳性发现,53(82%)是免疫球蛋白(Ig)的血管沉积,补语,或纤维蛋白原。最常见的血管沉积是纤维蛋白原(71%),其次是C3(62%),IgM(18%),IgA(6%),和IgG(3%)。纤维蛋白原沉积与高血压相关(p<0.03)。IgG的血管DIF沉积之间没有关联,IgA,和C3,随着年龄的增长,性别,合并症,疾病持续时间,和药物史。
结论:PPD中最常见的DIF发现是纤维蛋白原和C3的血管沉积,有或没有Ig存在。DIF的发现支持PPD的血管起源,但不支持免疫复合物介导的疾病。高血压与纤维蛋白原沉积有关,可能在其病理生理中起作用。
BACKGROUND: Pigmented purpuric dermatosis (PPD) is characterized by grouped petechiae, purpuric macules, and pigmentation in the bilateral lower extremities. It runs a chronic and relapsing course. Pathophysiology is poorly understood, but it has been proposed to be an immune-complex disease or capillaritis. This
study aimed to determine the incidence and patterns of positive direct immunofluorescence (DIF) findings in patients with clinically and histopathologically confirmed PPD. The association between DIF deposition type and clinical profile was also analyzed.
METHODS: Patients with a clinical and histopathologic PPD diagnosis who had undergone DIF studies at a tertiary medical center with attached dermatopathology and immunofluorescence diagnostic centers between January 2002 and December 2021 were included in this
study. Data on age, sex, disease duration, comorbidities, and drug intake were collected from medical records.
RESULTS: There were 65 patients who satisfied the inclusion criteria. Among them, 58 (89%) had at least one positive finding and 53 (82%) were vascular deposition of immunoglobulin (Ig), complement, or fibrinogen. The most common vascular deposition was fibrinogen (71%) followed by C3 (62%), IgM (18%), IgA (6%), and IgG (3%). Fibrinogen deposition was associated with hypertension (p < 0.03). There was no association between vascular DIF deposition of IgG, IgA, and C3, with age, sex, comorbidities, disease duration, and drug history.
CONCLUSIONS: The most common DIF findings in PPD were vascular deposition of fibrinogen and C3, with or without Ig presence. DIF findings supported a vascular origin in PPD but not an immune complex-mediated disease. Hypertension was associated with fibrinogen deposition and may play a role in its pathophysiology.