ACGME Learning Topics for Residents: Evaluation of Pancytopenia/Leukemia Stanford University/Lucile Packard Children’s Hospital
Case #2 A 4 year old previously healthy male presents to his pediatrician for evaluation of intermittent fevers x 5 days, easy bruising without history of trauma, and leg pain with now refusal to ambulate. In general, the child appears tired, but is non-toxic. His exam is notable for sub-centimeter anterior and posterior cervical lymphadenopathy, hepatomegaly approximately 1 cm below right costal margin, and a palpable spleen tip. He is noted to be pale, and has multiple bruises in various stages of healing over his pretibial regions, thighs, and upper arms, as well as scattered petechiae. He has no obvious long bone deformities or swelling of the joints. Given the history and physical exam, the physician is concerned about the possibility of an underlying malignant process, and draws a CBC with manual differential in his office. The results are as follows: Total white blood cell count is 1.3 with 2% segs, 1% bands, 90% lymphocytes, and 7% monocytes, hemoglobin is 5.6, and platelet count is 8K. 1. Based on the patient’s clinical presentation and pancytopenia, the differential diagnosis includes which of the following (more than answer may be correct): A. B. C. D.
Acute Lymphoblastic Leukmia (ALL) Aplastic Anemia Acute Monocytic Leukemia (AML) Osteosarcoma
A, B, C. Acute leukemia is the most common form of cancer in children, comprising approximately 30 percent of all childhood malignancies, with acute lymphoblastic leukemia (ALL) being four-to-five times more common than acute myeloid leukemia (AML). AML accounts for less than 10 percent of acute leukemias in children less than 10 years of age, and 20 percent of acute leukemias in children less than 15 years of age. The peak incidence for ALL occurs between 2 and 5 years of age, is more common among boys than girls, and among white than black children. The presenting signs and symptoms of acute leukemia reflect bone marrow infiltration and extramedullary spread of leukemic cells . Non-specific signs and symptoms, including pallor, fatigue, and fever, are often present. Bone pain, particularly affecting the long bones, and caused by leukemic involvement of the periosteum, is a presenting symptom in 20-40% of cases of acute leukemia. Bone pain in acute leukemia may also rarely be due to aseptic osteonecrosis because of malignant cell necrosis in the bone marrow. Radiographic changes in the bones may be present in as many as one-half Kristin Edgehouse, DO 2010
ACGME Learning Topics for Residents: Evaluation of Pancytopenia/Leukemia Stanford University/Lucile Packard Children’s Hospital
of cases. Lymphadenopathy, hepatomegaly, and splenomegaly are frequent manifestations of extramedullary leukemic spread. Most children with ALL have anemia and/or thrombocytopenia with either normal, increased, or depressed WBC counts, and lymphoblasts on peripheral smear. The degree of leukocyte count elevation remains one of the most important predictor of prognosis in ALL. Leukocytosis (WBC>10,000) occurs in approximately one half of patients with ALL. In 20% of patients, the initial leukocyte count is >50,000. Neutopenia (
