Comprehensive Osteopathic Medical Licensing Examination (COMLEX) Level 3 Practice Test

In IgA nephropathy, hematuria typically presents immediately after a respiratory infection. This condition is characterized by the deposition of immunoglobulin A (IgA) in the mesangial areas of the glomeruli, which often occurs following an upper respiratory tract infection. The immune response triggered by the infection can lead to increased production of IgA, causing a secondary immune-mediated glomerular injury that manifests as hematuria, often alongside proteinuria.

The timing of hematuria in this scenario is closely associated with the infectious trigger, making immediate onset after a respiratory infection a hallmark presentation. In clinical practice, patients frequently report the onset of blood in the urine coinciding with or shortly after experiencing symptoms of a viral or bacterial respiratory infection. This relationship becomes a key distinguishing feature of IgA nephropathy in differential diagnoses involving hematuria.

Other options, such as hematuria occurring two weeks after an infection, during an unrelated illness, or following a urinary tract infection, do not reflect the typical clinical course observed in IgA nephropathy and might suggest different underlying nephritides or urinary conditions. The immediate onset aligns perfectly with the pathophysiology of IgA nephropathy and emphasizes the importance of recognizing respiratory infections