Acute Lymphoblastic Leukemia: Morphology and Cytochemistry

A clinical case of acute lymphoblastic leukemia in a 21-year-old patient: blast morphology in blood and bone marrow, MPO, PAS, and lipid cytochemistry results.

Ekaterina Nozdrina 1 min December 5, 2025

Peripheral blood smear, blasts with cleaved nuclei

Peripheral blood smear, blast cells with a narrow rim of cytoplasm

Bone marrow smear, blasts with high nuclear-to-cytoplasmic ratio

Bone marrow smear, blast cells with prominent nucleoli

Blood smear, negative cytochemical reaction for myeloperoxidase

Blood smear, absence of peroxidase-positive granulation in blasts

Blood smear, weak diffuse PAS reaction in blast cells

Blood smear, lipid stain: negative blasts and positive neutrophil

Blood smear, control mature granulocyte with positive lipid reaction

🧬 “Sore throat → 93% blasts” ⚕ Patient is 21 years old! 🤒 weakness, t up to 38°C 💊 Self-medication with antipyretics → consultation with a therapist → CBC → immediate hospitalization in the hematology department.

🧪 CBC 📈 Leukocytes 66.3×10⁹/L ⚠ Hb 80 g/L 📉 Platelets 37×10⁹/L ❗Blasts 93%

🔍Blast Morphology 🩸 In the leukocyte differential count, 93% blasts with cleaved nuclei (photo 1, 2), lymphocytes 7%. 🦴 In the myelogram, 90% blasts with high nuclear-to-cytoplasmic ratio, with one nucleolus (photo 3,4).

🎨 Blast Cytochemistry 🚫 MPO negative (photo 5,6) 🟤 PAS in blasts weak (photo 7) ⚪ Lipids (-) negative in blasts (photo 8,9). In mature neutrophils (+) positive (control).

🧾 Presumptive diagnosis 🔎Acute lymphoblastic leukemia. ⏳ Awaiting IFT results