Department of Medical Microbiology & Immunology, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
Department of Dermatology, Faculty of Medicine, Zagazig University, Zagazig, Egypt.
Egypt J Immunol. 2020 Jan;27(1):141-155.
Chronic autoimmune urticaria is manifested by wheals and itching for 6 weeks, which is mediated mainly by autoantibodies against IgE receptors (FcεRIα). We aimed to assess the role of IgG autoantibody against FcεRIα in combination with autologous plasma skin test (APST), and autologous serum skin test (ASST) for autoimmune urticaria (AIU) diagnosis. This study was a case control study of 47 chronic spontaneous urticaria (CSU) patients and 47 healthy controls. Patients and control were subjected to ASST, APST, and ELISA assay of serum autoantibodies to FcεRIα. Histamine release assay (HRA) as the gold standard method for autoimmune urticaria diagnosis was performed after basophil percoll isolation and subjected to sera of both patients and control. The validity of ASST and autoantibodies to FcεRIα were determined in comparison to HRA. Autologous serum skin test was positive in 30 (63.8%) of CSU patients, and 12.7% of the healthy control (P=0.000). IgG autoantibodies to FcεRIα were demonstrated in 55.5% of the patients and were more common in patients with positive (80%) than negative ASST (11.7%) (P=0.000). There was significant positive correlation between "ASST" and "APST" positivity, and clinical severity as Spearman coefficient for this correlation was 0.477 (P=0.001). There was a significant association between IgG positivity to FcεRIα and disease severity as Spearman coefficient was 0.360 (P=0.02). Combined "ASST", "APST" and FcεRIα autoantibody tests revealed 100% sensitivity and 100% specificity for autoimmune urticaria diagnosis. In conclusion, combined anti-FcεRIα assay, with ASST, and APST improved the diagnosis of chronic autoimmune urticaria among patients with chronic spontaneous urticaria.
慢性自身免疫性荨麻疹的表现为风团和瘙痒持续 6 周，主要由针对 IgE 受体（FcεRIα）的自身抗体介导。我们旨在评估 IgG 自身抗体针对 FcεRIα与自身血浆皮肤试验（APST）和自身血清皮肤试验（ASST）联合用于自身免疫性荨麻疹（AIU）诊断的作用。这项研究是一项 47 例慢性自发性荨麻疹（CSU）患者和 47 例健康对照的病例对照研究。对患者和对照进行 ASST、APST 和血清 FcεRIα自身抗体的 ELISA 检测。采用组胺释放试验（HRA）作为自身免疫性荨麻疹诊断的金标准方法，对分离的嗜碱性粒细胞进行 Percoll 后，对患者和对照的血清进行 HRA。比较 ASST 和 FcεRIα自身抗体的有效性。自身血清皮肤试验在 30 例（63.8%）CSU 患者中为阳性，而在 12.7%的健康对照组中为阳性（P=0.000）。55.5%的患者检测到 FcεRIα的 IgG 自身抗体，且阳性 ASST（80%）患者比阴性 ASST（11.7%）患者更常见（P=0.000）。“ASST”和“APST”阳性之间存在显著正相关，Spearman 相关系数为 0.477（P=0.001）。FcεRIα IgG 阳性与疾病严重程度之间存在显著相关性，Spearman 相关系数为 0.360（P=0.02）。联合检测 FcεRIα、ASST 和 APST 对自身免疫性荨麻疹的诊断具有 100%的敏感性和 100%的特异性。总之，联合检测抗 FcεRIα、ASST 和 APST 可提高慢性自发性荨麻疹患者慢性自身免疫性荨麻疹的诊断率。
