A 4-year-old girl is brought to the clinic by her parents due to a two-week history of worsening fatigue, spontaneous bruising on her legs, and intermittent low-grade fevers. Physical examination reveals generalized lymphadenopathy and mild hepatosplenomegaly. The physician suspects acute lymphoblastic leukemia (ALL). Arrange the following diagnostic steps in the most appropriate chronological order, from initial screening to definitive staging.
- 1Obtain a complete blood count with differential
- 2Perform a peripheral blood smear review
- 3Conduct a bone marrow aspiration and biopsy
- 4Perform a lumbar puncture for cerebrospinal fluid analysis
Answer
The correct sequence is: Complete blood count with differential -> Peripheral blood smear review -> Bone marrow aspiration and biopsy -> Lumbar puncture.
The standard diagnostic pathway for pediatric leukemia begins with the least invasive screening (complete blood count), follows with morphological evaluation of the blood (peripheral smear), proceeds to definitive diagnosis (bone marrow aspiration), and concludes with staging for extramedullary disease (lumbar puncture).
Step-by-Step Solution
Key Concept
The diagnostic workup for pediatric acute lymphoblastic leukemia proceeds stepwise from basic non-invasive blood tests to definitive marrow evaluation, culminating in staging procedures.