What finding on urinalysis would indicate kidney involvement in a rheumatic condition?

What finding on urinalysis would indicate kidney involvement in a rheumatic condition?

• A. Protein and blood in urine when vasculitis affects the kidneys
• B. Crystalluria
• C. Glucosuria
• D. Bacteria in urine

Answer: (A)

When a rheumatic disease involves the kidneys, the inflammation often targets the glomeruli, causing them to leak. This leads to protein leaking into the urine (proteinuria) and red blood cells spilling into the urine (hematuria), which can be accompanied by red blood cell casts on microscopy. This combination is a direct sign of glomerular inflammation from vasculitis or immune complex–mediated processes, signaling kidney involvement. Other urinalysis findings don’t specifically point to rheumatic kidney involvement. Crystalluria reflects crystal formation in the urine from various metabolic or medication-related causes. Glucosuria indicates elevated blood glucose or proximal tubule dysfunction, not glomerular inflammation. Bacteria in the urine suggests infection rather than autoimmune kidney disease.

When a rheumatic disease involves the kidneys, the inflammation often targets the glomeruli, causing them to leak. This leads to protein leaking into the urine (proteinuria) and red blood cells spilling into the urine (hematuria), which can be accompanied by red blood cell casts on microscopy. This combination is a direct sign of glomerular inflammation from vasculitis or immune complex–mediated processes, signaling kidney involvement.

Other urinalysis findings don’t specifically point to rheumatic kidney involvement. Crystalluria reflects crystal formation in the urine from various metabolic or medication-related causes. Glucosuria indicates elevated blood glucose or proximal tubule dysfunction, not glomerular inflammation. Bacteria in the urine suggests infection rather than autoimmune kidney disease.