IgA Nephropathy (Berger Disease)
Overview
Plain-Language Overview
IgA Nephropathy (Berger Disease) is a condition that affects the kidneys, which are vital organs responsible for filtering waste from the blood. It occurs when a protein called immunoglobulin A (IgA) builds up in the kidney's filtering units, causing inflammation. This inflammation can lead to blood and protein leaking into the urine, which may be noticed as dark or bloody urine. Over time, the damage can reduce kidney function, potentially leading to chronic kidney disease. The disease often starts in childhood or early adulthood and can vary widely in severity among individuals.
Clinical Definition
IgA Nephropathy (Berger Disease) is a primary glomerulonephritis characterized by the deposition of IgA immune complexes in the mesangium of the glomeruli. The pathogenesis involves abnormal glycosylation of IgA1 molecules, leading to immune complex formation and mesangial proliferation. This results in glomerular inflammation and injury, manifesting clinically as hematuria and sometimes proteinuria. It is the most common cause of primary glomerulonephritis worldwide and can progress to end-stage renal disease in a subset of patients. The disease is often preceded by an upper respiratory tract infection, reflecting mucosal immune system involvement. Diagnosis and prognosis depend on clinical presentation and histopathologic findings.