What is the primary method used to diagnose acute lymphoblastic leukemia (ALL) in children?

• A. Blood test
• B. Bone marrow biopsy
• C. CT scan
• D. Ultrasound

Answer: (B)

The primary method used to diagnose acute lymphoblastic leukemia (ALL) in children is a bone marrow biopsy. This procedure involves the extraction of a small sample of bone marrow, usually from the posterior iliac crest, to examine the cells under a microscope. In cases of ALL, the biopsy will typically show an increased number of immature lymphoid cells, known as lymphoblasts, which confirm the diagnosis.

Bone marrow biopsy is critical not only for diagnosis but also for assessing the extent of the disease, as it provides definitive information about the cell types present in the marrow. While blood tests can indicate potential hematological abnormalities, they cannot alone confirm leukemia. Imaging studies such as CT scans and ultrasounds play a supportive role in evaluating any complications or detecting organ involvement but do not diagnose ALL directly. Thus, bone marrow biopsy is the cornerstone for confirming the presence of leukemia and for planning appropriate treatment.