A 5 year old boy is brought in by his parents, as he has been limping on his left leg for 4 days. Further questioning reveals that he was generally unwell during the preceding 3 weeks. There is no history of trauma and his medical history is unremarkable. X-rays of the left hip joint and knee are obtained, but no abnormalities are apparent.
WBC 4,500/mm3 (5,000 - 14,500) Neu: 30%; Lym: 65% Hb: 9.2 g/dL (11.5 - 14.5) Plt: 170,000/mm3 (250,000 - 550,000) Blood film: A normochromic normocytic anemia is seen; a few atypical cells are also noted.
ESR: 62 mm/1h (< 5) CRP: 24 mg/dL (< 6)
The bone marrow biopsy shows a hypercellular bone marrow with widespread infiltration of hematopoietic tissue by lymphoblasts. Normal hematopoietic elements are markedly reduced.
Appearance: Clear WBC: No polymorphs RBC: nil Gram stain: negative Glucose: 90 mg/dl (normal) Protein: 25 mg/dl (normal)