Leukemia

When a patient's WBC count is sky-high but they keep getting infections, the numbers are lying — those white cells aren't functional. Understanding why changes everything about your nursing priorities.

Leukemia is uncontrolled proliferation of immature, nonfunctional white blood cells (blasts) in the bone marrow. These blasts crowd out normal hematopoiesis, producing a predictable triad: infection (nonfunctional WBCs), bleeding (thrombocytopenia from marrow crowding), and anemia (decreased RBC production). Classification matters for NCLEX: acute versus chronic and lymphocytic versus myelocytic yield four types. Acute leukemias (ALL, AML) present suddenly with high blast counts, fever, fatigue, and bone pain — ALL peaks in children ages 2–5, AML in older adults. Chronic leukemias (CLL, CML) progress insidiously; CLL is the most common adult leukemia and may be discovered incidentally on routine CBC. CML is defined by the Philadelphia chromosome. Nursing priorities center on pancytopenia consequences: neutropenic precautions when ANC falls below 1,000 cells/mm³, monitoring for bleeding, managing fatigue, and recognizing tumor lysis syndrome during initial chemotherapy — watch for hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia.

Key Distinctions

Don't confuse a high WBC count with immune competence — in leukemia, those cells are immature blasts that cannot fight infection. Students mix up ALL (children, best prognosis of acute leukemias) with AML (older adults, poorer prognosis). Tumor lysis syndrome is a treatment complication, not a disease presentation — it occurs after chemo starts, not before.

Clinical Pearl

Think of leukemia as a factory that overproduces defective products: the shelves are full (high WBC) but nothing works. Count is up, function is down.