Leukemia Basics for Practical Nurses

Leukemia begins in blood-forming tissue, usually the bone marrow, when abnormal white-cell precursors multiply without normal control. The marrow’s production floor becomes occupied by cells that do not mature or function normally. As space and nutrients are diverted, production of red blood cells, platelets, and effective neutrophils falls. That single mechanism explains the central clinical pattern: - Anemia causes fatigue, pallor, exertional dyspnea, dizziness, and tachycardia because less hemoglobin is available to carry oxygen. - Thrombocytopenia causes petechiae, bruising, nosebleeds, gum bleeding, hematuria, or gastrointestinal bleeding because primary hemostasis is impaired. - Functional neutropenia causes infection risk even when the white blood cell count is high, because circulating blasts or abnormal lymphocytes do not provide normal antimicrobial defense. The total white blood cell count can therefore mislead. A markedly elevated count does not mean the patient is protected from infection. The differential count, absolute neutrophil count, smear, symptoms, and treatment history matter more than the total count alone. Leukemia may also infiltrate lymph nodes, spleen, liver, skin, bone, or the central nervous system. Those effects produce lymphadenopathy, splenomegaly, abdominal fullness,...