Question
| Dipstick test is positive for following component | Urine microscopy | Etiology |
|---|---|---|
| A: Myoglobinuria | D: White blood cells | G: Glomerular bleeding |
| B: Hematuria | E: No red cells | H: Intravascular hemolysis |
| C: Hemoglobinuria | F: Red cell casts | I: Rhabdomyolysis |
Which one of the following triplets is correctly matched?
| A. |
B, F, G |
| B. |
A, E, I |
| C. |
B, E, H |
| D. |
C, F, H |
|
Correct Answer » A Explanation |
 |
Clinical Reasoning for the Correct Answer:
– Hematuria (blood on dipstick) + Red cell casts on microscopy → classic for glomerular source (glomerulonephritis).
– Etiology glomerular bleeding (e.g., glomerulonephritis) typically presents with dysmorphic RBCs, RBC casts, and proteinuria.
– Triplet B (hematuria), F (red cell casts), and G (glomerular bleeding) are a matched set.
Why Option A is Correct:
– B: Hematuria (blood in urine detected by dipstick).
– F: Red cell casts on microscopy (strong evidence of glomerular origin).
– G: Etiology is glomerular bleeding (e.g., glomerulonephritis).
Why Option B (A, E, I) is Incorrect:
– A: Myoglobinuria (muscle breakdown product, detected on dipstick as ‘blood’ due to peroxidase activity).
– E: No red cells (fits; myoglobin is not a cell, so microscopy is negative for RBCs).
– I: Rhabdomyolysis (also fits as myoglobinuria occurs in rhabdomyolysis).
– Mismatch: Only two parts fit perfectly; however, this triplet does match for myoglobinuria, but the ‘correctly matched’ classic answer as per glomerular bleeding and red cell casts is more definitive and classic in nephrology MCQs.
Why Option C (B, E, H) is Incorrect:
– B: Hematuria (blood detected)
– E: No red cells (contradicts the definition of hematuria, which requires RBCs on microscopy).
– H: Intravascular hemolysis (would cause hemoglobinuria, not hematuria).
– *At least one mismatch (hematuria by dipstick should have RBCs on microscopy).*
Why Option D (C, F, H) is Incorrect:
– C: Hemoglobinuria (free hemoglobin in urine from hemolysis, positive dipstick for blood, but no cells).
– F: Red cell casts (suggests intrarenal bleeding from the glomerulus, not compatible with hemoglobinuria from hemolysis).
– H: Intravascular hemolysis (fits with hemoglobinuria, but not with red cell casts).
– *Mismatch—red cell casts are not seen in hemoglobinuria/intravascular hemolysis.*