The CBC Decoded: Interpretation, Red Flags, and When to Order a Peripheral Blood Smear (Adults & Peds)
The CBC Decoded: Interpretation, Red Flags, and When to Order a Peripheral Blood Smear (Adults & Peds) The most ordered lab in medicine—and the one most often skimmed instead of read. Here's how to actually use it. The CBC is the single most frequently ordered lab test in medicine, yet most clinicians glance at the hemoglobin, maybe the WBC, and move on. The truth is that every number on the CBC tells a story, and the components you're ignoring—the MCV, RDW, differential, platelet indices—may be the ones that catch the diagnosis everyone else is missing. And when the numbers don't add up? That's when the peripheral blood smear becomes your most powerful diagnostic tool. Part 1: The Red Cell Line Hemoglobin, Hematocrit, and RBC Count These tell you whether the patient is anemic (low) or polycythemic (high). But the why lives in the indices. MCV: The Anemia Classifier Mean Corpuscular Volume is the single most useful number for classifying anemia. It tells you the a...