Objective:

To investigate the clinical manifestations and prognostic implications of anti-GBM disease with overlapping autoimmune serological profiles.

Approach:

• Patient Enrollment: Retrospective study enrolling patients diagnosed with anti-GBM disease at the First Affiliated Hospital with Nanjing Medical University from January 2017 to January 2024.
• Cohort Stratification: Patients were stratified into three groups based on serological profiles: classic anti-GBM group, ANCA-anti-GBM double-positive group, and anti-GBM-non-ANCA autoantibody overlap group.
• Data Comparison: Clinical, pathological, treatment, and outcome characteristics were compared across the three groups, with landmark analysis for prognostic discrepancies.

Key Findings:

• 67 patients were enrolled: 30 in the classic anti-GBM group, 18 in the ANCA-anti-GBM double-positive group, and 19 in the anti-GBM-non-ANCA autoantibody overlap group.
• The ANCA-anti-GBM double-positive group had the highest mean age at onset.
• Significant differences in baseline anti-GBM antibody titers were observed across groups (p = 0.044).
• No significant differences in clinical characteristics, renal pathological findings, or therapeutic regimens were noted.
• Distinct trends in early survival outcomes were observed, with the ANCA-anti-GBM double-positive group showing the poorest early survival.

Interpretation:

The study identifies distinct phenotypic traits of anti-GBM disease with concurrent autoimmune antibodies.

Limitations:

• The study is retrospective and conducted at a single center, which may limit generalizability.
• The sample size is relatively small, which may affect the statistical power of the findings.

Conclusion:

The findings suggest the need for further investigation into treatment strategies for patients with anti-GBM disease overlapping with non-ANCA autoantibodies.