Certified Pediatric Hematology Oncology Nurse (CPHON) Practice Exam 2025 – Comprehensive All-in-One Resource for Exam Excellence!

In the context of Fanconi Anemia, macrocytic anemia is one of the initial laboratory findings due to the underlying disorder affecting the bone marrow's ability to produce healthy blood cells. Fanconi Anemia is characterized by defects in DNA repair mechanisms, which impact the ability of the bone marrow to generate normal erythrocytes, leading to a predominant presence of larger than normal red blood cells when the anemia manifests. This macrocytic feature is often a result of the bone marrow's compensatory response to the effective reduction of red blood cell production and possibly associated deficiencies in nutrients such as vitamin B12 or folate.

Understanding other laboratory findings in this condition helps to contextualize why macrocytic anemia is particularly noted. For example, neutrophilia would indicate an increase in neutrophils typically associated with infections or inflammatory responses, hypercellular bone marrow would suggest an increase in cell production, and thrombocytosis would imply a rise in platelet count often linked with reactive processes. However, in the case of Fanconi Anemia, the hallmark is indeed the macrocytic anemia due to ineffective hematopoiesis.