Shahidullah M, Lee Y S, Khor C J, Ratnam K V
National Skin Centre, National University Hospital.
Ann Acad Med Singap. 1995 Nov;24(6):789-92.
We studied 100 cases of chronic cutaneous discoid lupus erythematosus (DLE) to evaluate the diagnostic sensitivity of immunoreactant deposition and its possible role in basement membrane thickening. Histopathology was diagnostic in 71% of cases. Sixty-two percent (41/66) of lesions with thickened and 50% (17/34) with normal basement membrane had immunoreactant deposition. Ultrastructural study of 6 cases (3 with and 3 without immunoreactant deposition) with thickened basement membrane all showed reduplication of the lamina densa. Thickening of the basement membrane appears to be contributed mainly by reduplication of the lamina densa rather than by immunoreactant deposition. The direct immunofluorescence (DIF) test of lesional skin was positive in 58% of patients and was independent of duration of lesion, age and sex. Light microscopy has greater diagnostic sensitivity in confirming DLE lesions than DIF. Direct salt split skin technique did not increase DIF sensitivity. Scalp lesions showed the highest frequency (83%) of immunoreactant deposition. As C1q was the commonest immunoreactant found in our study, we suggest that it should be routinely used when DIF is employed in the evaluation of DLE. DIF is especially helpful in confirming cicatricial alopecia due to DLE.
我们研究了100例慢性皮肤盘状红斑狼疮（DLE），以评估免疫反应物沉积的诊断敏感性及其在基底膜增厚中的可能作用。组织病理学诊断出71%的病例。基底膜增厚的病变中有62%（41/66）和基底膜正常的病变中有50%（17/34）存在免疫反应物沉积。对6例基底膜增厚的病例（3例有免疫反应物沉积，3例无）进行超微结构研究，均显示致密板重复。基底膜增厚似乎主要是由致密板重复引起的，而不是由免疫反应物沉积引起的。58%的患者病变皮肤直接免疫荧光（DIF）试验呈阳性，且与病变持续时间、年龄和性别无关。在确认DLE病变方面，光学显微镜比DIF具有更高的诊断敏感性。直接盐裂皮肤技术并未提高DIF的敏感性。头皮病变中免疫反应物沉积的频率最高（83%）。由于C1q是我们研究中最常见的免疫反应物，我们建议在使用DIF评估DLE时应常规使用。DIF在确认DLE所致瘢痕性脱发方面特别有帮助。
