To the Editor:Laboratory diagnostic methods of bullous pemphigoid(BP)include direct immunofluorescence(DIF)microscopy,BP180 NC16A enzyme-linked immunosorbent assays(ELISA),and indirect immunofluorescence using salt-split skin(ssIIF)in our daily clinical practice.Immunofluorescence(IF)studies are important parts of the laboratory workup for BP.DIF is regarded as the gold standard for BP diagnosis;however,it is not specific and can also be found in other acquired autoimmune subepidermal blistering dermatosis.ssIIF was found to have a specificity of 100%for BP diagnosis and in some guidelines,it is recommended to perform ssIIF in every patient with clinically suspected BP.[1]To date,it is still not defined whether ssIIF can be used as a routine diagnosis method of BP.The BP180 NC16A ELISA is a practical and reliable diagnostic test for BP;however,the false-positive results of BP180 NCA6A ELISA were recently reported in a wide range of dermatoses,which might cause its uncertainty in the diagnosis of BP.Thus,we conducted a single center retrospective study to compare diagnostic values of these tests for BP from Hospital for Skin Diseases,Chinese Academy of Medical Sciences between January 2014 and January 2019.It was approved by the local medical ethical committee(No.2017-KY-022)and consent was obtained from patients prior to serum collection.
Suo LiRuiyu XiangKe JingZhiliang LiYuan WangHanmei ZhangXiaoguang LiSuying Feng
