A four year old boy was admitted with a history of abdominal pain and fever for two months maculopapular rash for ten days, and dry cough, dyspnea and wheezing for three days. One examination liver and spleen were enlarged 4 cm and 3 cm respectively below the costal margins. His hemoglobin was 10.0 g/dl, platelet count 37 x 109/L and total leukocyte count 70 x 109/L, which included 80% eosinophils Bone marrow examination revealed a cellular marrow comprising of 45% blasts and 34% Eosinophils and eosinophilic precursors. The blasts stained negative for myeloperoxidase and non-specific esterase and were positive for CD19, CD10, CD22 and CD20. Which one of the following is the most likely diagnosis –
A four year old boy was admitted with a history of abdominal pain and fever for two months maculopapular rash for ten days, and dry cough, dyspnea and wheezing for three days. One examination liver and spleen were enlarged 4 cm and 3 cm respectively below the costal margins. His hemoglobin was 10.0 g/dl, platelet count 37 x 109/L and total leukocyte count 70 x 109/L, which included 80% eosinophils Bone marrow examination revealed a cellular marrow comprising of 45% blasts and 34% Eosinophils and eosinophilic precursors. The blasts stained negative for myeloperoxidase and non-specific esterase and were positive for CD19, CD10, CD22 and CD20. Which one of the following is the most likely diagnosis –
💡 Explanation
Okay, let's tackle this question. The patient is a four-year-old boy with symptoms like abdominal pain, fever, rash, and respiratory issues. The lab results show pancytopenia with a high eosinophil count and blasts in the bone marrow. The blasts are positive for B-cell markers like CD19, CD10, CD22, and CD20. That points towards a B-cell lymphoblastic leukemia. The presence of eosinophilia might suggest a variant, like B-ALL with eosinophilia. The blasts being negative for myeloperoxidase and non-specific esterase rules out myeloid origin. So the most likely diagnosis is B-cell acute lymphoblastic leukemia with associated eosinophilia. The options probably include other leukemias or myeloproliferative disorders, but the B-cell markers make it clear.
**Core Concept**
This question tests the diagnosis of **B-cell acute lymphoblastic leukemia (B-ALL)** with **eosinophilia**, emphasizing immunophenotypic differentiation from myeloid or other lymphoid malignancies. Key markers include **CD19, CD10, CD22, CD20** (B-cell lineage) and **absence of myeloperoxidase/non-specific esterase** (excluding myeloid lineage).
**Why the Correct Answer is Right**
The bone marrow shows **45% blasts** with **80% eosinophils/eosinophilic precursors**, indicating a mixed lineage process. Blasts are **positive for B-cell markers (CD19, CD10, CD22, CD20)** and **negative for myeloid markers (myeloperoxidase, nonspecific esterase)**, confirming a **B-lymphoblastic lineage**. The eosinophilia suggests a **reactive component** or a **variant of B-ALL** with eosinophilic involvement, such as **B-ALL with eosinophilia** or **leukoerythroblastic reaction**. The clinical triad of **hepatosplenomegaly, pancytopenia, and blasts** in marrow is classic for **acute leukemia**.
**Why Each Wrong Option is Incorrect**
**Option A:** *Chronic myeloid leukemia (CML)* is incorrect because it arises from a myeloid lineage (positive myeloperoxidase) and typically presents in adults, not children.
**Option B:** *Acute myeloid leukemia (AML)* is ruled out by negative myeloperoxidase and nonspecific esterase in blasts, which are hallmark myeloid markers.
**Option C:** *Hodgkin lymphoma* is incorrect as it involves lymph nodes, not marrow blasts, and lacks B-cell markers.
**Option D:** *Eosinophilic leukemia* (a myeloid neoplasm) is excluded by the B-cell immunophenotype of blasts.
**Clinical Pearl / High-Yield Fact**
**CD19, CD10, CD22, CD20** positivity in blasts confirms **B-ALL**. Always correlate **morphology**, **cytochemistry**, and **immunophenotype** to distinguish lymphoid vs. myeloid leukemias. **Eosinophilia** in leukemia
✓ Correct Answer: C. Acute myeloid leukemia with eosinophilia
📤 Share this MCQ
Share Card Preview
👆 1080x1080 square card — fills the full width in WhatsApp and Telegram