Autoimmune Interaction in the Coexistence of Hashimoto's Thyroiditis and IgA Nephropathy: Case Report of Severe Hypothyroidism and Rapidly Progressive Glomerulonephritis

Immunoglobulin A nephropathy (IgAN) is the most common cause of primary glomerulonephritis worldwide. It can be associated with other autoimmune diseases. This case aims to present a patient with IgA nephropathy associated with severe hypothyroidism.A 66-year-old male with type 2 diabetes mellitus, hypertension and chronic ischemic heart disease was admitted with complaints of widespread edema. Laboratory tests revealed elevated creatinine and thyroid-stimulating hormone. Initially, a kidney-protective diet and fluid intake regulation were instituted. Diuretic treatment was started due to hypervolemia, levothyroxine was initiated for hypothyroidism. Due to progression in creatinine and diuretic-resistant hypervolemia, hemodialysis was started. At this point, renal biopsy confirmed IgA nephropathy, therefore steroid and immunosuppressive treatments were initiated. The patient showed improvement in edema and general condition. IgA nephropathy is known to occur alongside various autoimmune diseases. This case highlights the importance of considering autoimmune thyroiditis in patients presenting with rapidly progressive glomerulonephritis.