Mercury poisoning-associated membranous nephropathy and autoimmune encephalitis

• DOI: 10.1186/s12882-025-04082-7
• Publication Date: 2025-03-24T22:35:30Z
• Authors: Caihong Liu; Yongxiu Huang; Wei Wei; Xinyu Hu; Jing Yang; Yuliang Zhao
• Keywords: Membranous Nephropathy; Mercury; Nephrology; Autoimmune encephalitis

Mercury intoxication is not uncommon and often presents with diverse symptoms of multiple systems. While neurological disorders renal impairments have been examined in isolation, the concurrent occurrence systemic linked to immune dysregulation infrequently observed. Here, we report an unusual case that a 55-year-old male patient, who scrap merchant, was admitted our center for neuropsychiatric disturbances, including incoherent speech hallucinations. He initially diagnosed autoimmune encephalitis (AE) because double positivity CASPR2 LGl1 antibodies serum. The patient later presented pruritus nephrotic syndrome, where biopsy revealed membranous nephropathy (MN). In view mercury exposure history elevated urinary level, AE MN were suspected be related poisoning. achieved full recovery following four-month treatment regimen comprising immunosuppressants mercury-chelating agents, underscoring significance recognizing environmental toxins such as coexisting diseases different systems MN.