HSBTE DMLT IVth Semester. Laboratory diagnosis of various leukemias, Acute leukemias Laboratory diagnosis, Differentiation of ALL and AML, Chronic Myeloid leukemia (chronic myelogenous leukemia or CML) laboratory diagnosis. Unit III.

Laboratory diagnosis of various leukemias

The laboratory diagnosis of leukemias involves a combination of clinical assessments, blood tests, bone marrow examinations, and advanced molecular techniques. The goal is to identify and classify the specific type of leukemia, determine its stage, and guide appropriate treatment.

Acute leukemias Laboratory diagnosis

A. Hematological Investigation: Presence of anemia, decreased, normal, or increased WBCs count up to 2 lakh/cu mm. Thrombocytopenia may occur.

B. Blood Film Examination:

• 1. In AML, blasts may have Auer rods and other abnormal cells such as promyelocytes, myelocytes, agranular neutrophils, and myelomonocyte cells.

• 2. In erythroleukemia, normoblasts may be present in smaller numbers,

• 3. Bone marrow is hypercellular.

• 4. In ALL, it is difficult to aspirate due to increased reticulin fiber.

Differentiation of ALL and AML

Clinical features and morphology study of cells after staining could not differentiate ALL and AML. Cytochemistry is used to differentiate ALL and AML.

1. Peroxidase test: ALL shows negative results. AML shows positive results along with Auer rod presence.

2. Sudan Black B: ALL shows negative results. AML shows positive results.

3. PAS test: ALL shows positive (coarse) and AML shows positive (fine)

4. Acid phosphate test: ALL shows positive results. AML shows a negative result.

C. Other Investigations

• 1. Disseminated intravascular coagulation (DIC) is positive in promyelocytic leukemia.

• 2. Lumbar puncture shows raised spinal fluid pressure. It contains leukemic cells in patients suffering from meningeal leukemia.

Chronic Myeloid leukemia (chronic myelogenous leukemia or CML) laboratory diagnosis

A. Diagnostic clinical and laboratory features:

1. Leucocytes count more than 50,000/ cu mm and sometimes more than 5 lakhs/ cu mm.

2. Level of neutrophils and myelocytes more than blast cells and promyelocytes.

3. Presence of Philadelphia chromosomes on cytogenetic analysis of blood.

4. Hyper cellular bone marrow.

5. Very low neutrophil alkaline phosphatase

6. Increase in circulating basophils

7. Anemia

8. Increased, decreased, or normal platelet count.

Chronic lymphocytic leukemia (CLL) laboratory diagnosis

1. Absolute leucocyte count above 5000 cu mm.

2. Normocytic, normochromic anaemia

3. Thrombocytopenia

4. Bone marrow aspiration: 25 to 95% of cells are lymphocytes.

5. Reduced concentration of serum immunoglobulin

Dr Pramila Singh