• Leukemia is the most common pediatric malignancy, accounting for 30% of pediatric cancer
  • Acute lymphoblastic leukemia (ALL) is 5 times more common than acute myeloid leukemia (AML)
  • ALL is more common in early childhood, while AML has biphasic peaks in infancy and adolescence

History and Physical:

  • Nonspecific symptoms are common, and may include fever, fatigue, and anorexia
  • More specific signs include splenomegaly, hepatomegaly, generalized lymphadenopathy, pallor, ecchymoses, and petechiae
  • DIC is concerning for acute promyelocytic leukemia (APML)
  • Mediastinal mass (potentially leading to SVC syndrome and respiratory distress) is concerning for T-cell ALL
  • Headache, vomiting, lethargy, and cranial nerve abnormalities are concerning for CNS involvement
    • Mass effect due to chloroma is concerning for AML
  • Testicular pain or swelling is concerning for testicular involvement

Differential Diagnosis:

  • Malignant conditions: Burkitt lymphoma, aplastic anemia, small round blue cell tumors
  • Non-malignant conditions: immune thrombocytopenia, B12/folate deficiency, infections (e.g. HIV, EBV, tuberculosis)
  • Medications (e.g. chemotherapeutic agents, valproic acid, mycophenolate mofetil)

Laboratory Studies:

Radiographic Studies:

  • Chest imaging (either plain films or CT) is useful when there is concern for mediastinal mass
  • Head imaging can be obtained when there is concern for intracranial involvement
  • Bony radiographs can show metaphyseal radiolucent bands, subperiosteal new bone formation, and osteolytic lesions of the cortex and medullary cavity


Management and Disposition:

  • ED management for patients with suspected leukemia involves consultation with pediatric hematology/oncology specialists, as well as management of complications (see table). Febrile patients should receive broad-spectrum antibiotics
  • Patients with high suspicion for leukemia should be admitted for further evaluation and management


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  2. Hunger SP, Mullighan CG. Acute Lymphoblastic Leukemia in Children. N Engl J Med. 2015 Oct 15;373(16):1541-52. doi: 10.1056/NEJMra1400972. PMID: 26465987.
  3. Madhusoodhan PP, Carroll WL, Bhatla T. Progress and Prospects in Pediatric Leukemia. Curr Probl Pediatr Adolesc Health Care. 2016 Jul;46(7):229-241. doi: 10.1016/j.cppeds.2016.04.003. Epub 2016 Jun 6. PMID: 27283082.
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