Study on the diagnostic criteria of syndrome of dampness obstruction in idiopathic membranous nephropathy based on expert consensus.

Objective: To reach consensus on the diagnostic criteria of syndrome of dampness obstruction in idiopathic membranous nephropathy (IMN) patients by literature research and expert investigation (interviews and a Delphi method).

Methods: Our study was consistent with T/CACM 1336-2020. We searched the monographs and references published in the past 40 years (1983-2022), and established the diagnostic criteria pool of water-dampness syndrome and dampness-turbidity syndrome in Traditional Chinese Medicine (TCM) based on literature by using frequency statistics and correlation analysis. Expert investigation (interview method and two rounds of Delphi method) was used to form the diagnostic criteria of water-dampness syndrome and dampness-turbidity syndrome of idiopathic membranous nephropathy. Clinical diagnostic test research was carried out, and compared with "Diagnostic Criteria for dampness syndrome" (T/CACM 1454-2023) to evaluate the authenticity, reliability and clinical application value of the standard.

Results: A total of 122 relevant guides, standards, monographs and documents were included through searching books and Chinese databases. Four experts were interviewed and two rounds of delphi method (75 experts nationwide) were carried out. The experts' opinions are relatively concentrated and the differences are small. Based on the weight of each index, the diagnostic criteria indexes of water-dampness syndrome and dampness-turbidity syndrome were selected. After discussion by the core group members, the diagnostic model of "necessary symptoms and optional symptoms" was established, and the final diagnostic criteria of water-dampness syndrome and dampness-turbidity syndrome were established. One hundred and ninety-one inpatients and outpatients of Guangdong Provincial Hospital of Chinese Medicine from January 2021 to February 2023 were included in Diagnostic test study. There was no statistical difference in gender, age and course of disease (P > 0.05). The sensitivity and specificity of the trial standard were 90.34% and 73.33% respectively, while the sensitivity and specificity of T/CACM 1454-2023 were 99.43% and 6.67%, respectively.

Conclusions: The consensus-based diagnostic criteria for IMN can be widely incorporated in TCM. A further clinical study will be conducted to analyze the diagnosis value and cut-off score of our IMN criteria.