[Value of direct immunofluorescence in the diagnosis of oral mucosal pemphigus vulgaris: A retrospective study based on multi-index combined analysis].

OBJECTIVE

To clarify the diagnostic efficacy of various diagnostic methods through multi-index combined analysis, and to explore the core diagnostic value of direct immunofluorescence (DIF) in oral mucosal pemphigus vulgaris (PV).

METHODS

A total of 53 patients with confirmed oral mucosal PV were included, retrospectively. Their data of DIF, histopathology, serum enzyme-linked immunosorbent assay (ELISA) and clinical diagnosis were systematically analyzed, and diagnostic efficacy of each method was evaluated using indicators, such as sensitivity, specificity, and area under curve (AUC) of the receiver operating characteristic (ROC) curve.

RESULTS

The results showed that among the 53 patients, middle-aged and elderly females were predominant, the buccal mucosa was the most common involved site, and most patients had a history of blistering. The positive rate of DIF was 96.23%, mainly manifested as a reticular fluorescent deposition between epithelial spinous cells, demonstrating the highest diagnostic value with a sensitivity of 96.23%, specificity of 100.00%, and AUC of 0.981. Histopathology ranked second, with a sensitivity of 94.34%, a specificity of 100.00%, and an AUC value of 0.972. The ELISA test had a sensitivity of 82.61%, a specificity of 82.35%, and an AUC value of 0.825. Although the sensitivity of clinical diagnosis was acceptable, its specificity was relatively low. Additionally, DIF exhibited complementarity with histopathology, ELISA, and clinical diagnosis, and combined testing could improve diagnostic accuracy.

CONCLUSION

DIF is the "gold standard" for the diagnosis of oral mucosal PV. A comprehensive diagnostic workflow of "clinical manifestation-DIF-histopathology-ELISA" is proposed. This integrated diagnostic system not only significantly improves the accuracy of oral mucosal PV diagnosis but also aligns with the core principles of precision medicine, providing a basis for indivi-dualized treatment.