A patient with multiple myeloma has a negative urine protein dipstick, but the sulfosalicylic acid test is strongly positive. What is the most likely explanation?
1The sulfosalicylic acid test gives a falsely positive result in this patient
2The specimen is too dilute for the dipstick to react
3The urine pH is alkaline and alters the reaction
4The dipstick is most sensitive to albumin and may miss free light chains✓ 정답
해설
The protein pad of the reagent strip is designed to react mainly with albumin, so it misses free light chains. Sulfosalicylic acid precipitates protein in general and therefore detects light chains as well. The question tests the difference in principle between the two methods.