Complementary and alternative medicine-associated membranous nephropathy: a systematic review

Area of Science:

• Nephrology
• Toxicology
• Immunology

Background:

• Complementary and alternative medicine (CAM) use is an underrecognized cause of membranous nephropathy (MN).
• The prevalence and specific etiologies of CAM-induced MN require further investigation.
• This review addresses the incidence, clinical presentation, and treatment outcomes of CAM-associated MN.

Purpose of the Study:

• To systematically review the incidence of MN induced by various CAM modalities.
• To describe the clinical presentation of patients with CAM-associated MN.
• To analyze treatment responses in patients with CAM-associated MN.

Main Methods:

• Systematic review adhering to PRISMA guidelines.
• Searches conducted in major databases (MEDLINE, Embase, PubMed, Cochrane Library) and reference lists.
• Inclusion of English-language studies from 2010 onwards reporting MN with CAM exposure; independent data extraction and eligibility assessment.

Main Results:

• Twenty-seven studies (10 case reports, 10 case series, 5 cohort, 2 case-control) involving 262 patients (66% female) with biopsy-proven MN were included.
• Mercury exposure (from traditional medicines, skin creams, hair dyes) was reported in 87.5% of cases.
• Neural epidermal growth factor-like 1 protein (NELL-1) antibodies were positive in 94.7% of 113 tested patients. Conservative management yielded complete remission in 64% and partial remission in 24% of cases.

Conclusions:

• Most CAM-associated MN cases involve mercury exposure and NELL-1 antibodies.
• Clinical outcomes did not differ significantly between immunosuppressive therapy and conservative management.
• Highlights the importance of considering CAM exposure in MN diagnosis and management.