NCLEX Review Guide: Aplastic Anemia

Understanding Aplastic Anemia

• Aplastic anemia is a rare bone marrow failure disorder where the bone marrow stops producing adequate blood cells, resulting in pancytopenia (decreased RBCs, WBCs, and platelets).
• The bone marrow becomes hypocellular with fatty tissue replacing normal hematopoietic cells, leading to severe deficiencies in all blood cell lines.

Causes of Aplastic Anemia

• Idiopathic cases account for 70-80% of aplastic anemia with unknown etiology. Acquired causes include exposure to benzene, radiation, chemotherapy agents, and certain medications like chloramphenicol.
• Viral infections such as hepatitis, Epstein-Barr virus, and parvovirus B19 can trigger autoimmune destruction of bone marrow stem cells.

Signs & Symptoms by Cell Line

• Anemia symptoms: Fatigue, weakness, pallor, shortness of breath, and decreased exercise tolerance due to low RBC count and reduced oxygen-carrying capacity.
• Thrombocytopenia symptoms: Petechiae, purpura, easy bruising, bleeding gums, and prolonged bleeding from minor cuts due to platelet deficiency.
• Neutropenia symptoms: Increased susceptibility to infections, fever, and delayed wound healing due to decreased white blood cell count.

Laboratory & Diagnostic Tests

1. Complete Blood Count (CBC): Shows pancytopenia with low reticulocyte count, indicating bone marrow failure rather than hemolysis or bleeding.
2. Bone marrow biopsy: Gold standard showing hypocellular marrow with <30% cellularity and fatty tissue replacement of normal hematopoietic elements.
3. Flow cytometry: Rules out paroxysmal nocturnal hemoglobinuria (PNH) and helps differentiate from other bone marrow disorders.

Therapeutic Interventions

• Bone marrow transplantation is the treatment of choice for patients under 40 with severe aplastic anemia and compatible donor, offering potential cure with 80-90% survival rates.
• Immunosuppressive therapy with antithymocyte globulin (ATG) and cyclosporine is used for patients not eligible for transplant, achieving response in 60-70% of cases.
• Supportive care includes blood transfusions, antibiotics for infections, and growth factors like eltrombopag to stimulate platelet production.

Priority Nursing Actions

1. Infection prevention: Implement neutropenic precautions including hand hygiene, avoiding crowds, monitoring for fever, and prompt antibiotic administration for temperatures >100.4°F.
2. Bleeding precautions: Use soft toothbrush, avoid injections when possible, monitor for signs of bleeding, and maintain platelet count >10,000/μL through transfusions.
3. Activity modification: Balance rest with gentle activity to prevent fatigue while maintaining muscle strength and preventing complications of immobility.
4. Psychosocial support: Provide emotional support for chronic illness, connect with support groups, and educate about treatment options and prognosis.