Conclusion:This case represents the first report of IgG4-TIN coexisting with renal AA amyloidosis.Chronic inflammation from IgG4-RD may drive persistent SAA elevation, leading to secondary AA amyloid deposition.Accurate diagnosis requires histopathological evaluation with Congo red and IgG4/AA immunostaining.Immunosuppressive therapy achieved significant improvement in renal and systemic parameters.IgG4-RD should be recognized as a potential, though rare, cause of secondary AA amyloidosis, underscoring the importance of renal biopsy in patients with unexplained renal dysfunction and elevated IgG4.I have no potential conflict of interest to disclose.I did not use generative AI and AI-assisted technologies in the writing process.
Ashktorab et al. (Wed,) studied this question.