Certified Pediatric Hematology Oncology Nurse (CPHON) 2025 – 400 Free Practice Questions to Pass the Exam

Diamond-Blackfan Anemia (DBA) is characterized by pure red cell aplasia, which means there is a significant reduction or absence of red blood cells due to a failure in erythropoiesis primarily affecting red cell progenitors in the bone marrow. This condition typically leads to macrocytic anemia, meaning that although there are fewer red blood cells produced, those that are formed tend to be larger than normal due to ineffective erythropoiesis.

The presence of pure red cell aplasia is a defining feature of DBA and is critical for establishing the diagnosis. This absence of red blood cells occurs while other hematological cell lines, such as white blood cells and platelets, are usually unaffected, which distinguishes it from other types of anemia or bone marrow failure syndromes.

In contrast, the other options pertain to different conditions or findings not associated with DBA. For example, normal white blood cell count and increased platelet levels can be seen in other hematologic conditions but do not represent the hallmark of DBA. Iron deficiency anemia, while common, is unrelated to the pathophysiological mechanisms underlying DBA. The specificity of pure red cell aplasia makes it the correct choice in identifying the key hematological finding associated with Diamond-Blackfan An