158) A 55 year old man comes to the Emergency Room complaining of left upper quadrant discomfort. His physical examination reveals Splenomegaly. Laboratory investigations were sent but there was a significant delay in sending the specimen to the laboratory after collection. Laboratory investigations reveal a WBC count of 110,000/µl with neutrophilia, basophilia and eosinophilia and Serum potassium of 3.0/µl. Leucocyte Alkaline Phosphatase level is low. A bone marrow biopsy is obtained and the results are pending. The most likely explanation of the patients hypokalemia :
A) Delay in specimen transport to lab
B) Marked Leucocytosis and Delay in specimen transport
C) Tumor Lysis
D) Splenomegaly
E) Renal loss
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in tumor lysis is hyperkalemia,LAP is low in CML,but i dont knw reason of low K ,may be its delay in specimen,but i guess cells hemolyze and K shud increase:[ so tell me correct ans plz
I think the answer is E: Renal loss.
E
It is pseudohypokalemia/ falsely low potassium level
Pseudohypokalemia occurs in patients with chronic myelocytic leukemia with a WBC count > 105/μL when the specimen remains at room temperature before being processed because of uptake of serum K by abnormal WBC in the sample.
It can be prevented by prompt separation of plasma or serum in blood samples.
Ans is
B) Marked Leucocytosis and Delay in specimen transport