Microscopic Description and Laboratory Data -- Macrocytic Anemia


MICROSCOPIC DESCRIPTION:

Following transfusion with packed red blood cells a complete blood cell count was performed which revealed a macrocytic normochromic anemia (Table 1). The patient had white blood cell and platelet counts which were in the normal range. A manual white blood cell differential count and a review of the peripheral blood smear was performed. Numerous blasts (Table 2) with immature chromatin containing multiple nucleoli and scant blue cytoplasm (Figure 6) were identified. Some of the blasts contained a moderate amount of blue cytoplasm with frayed cytoplasm (Figure 7). Platelets were adequate in number with many giant forms present. A megakaryocyte nucleus was also identified (Figure 8). The red blood cell morphology showed severe anisocytosis (Table 1) and poikilocytosis with macrocytes present (Figures 6, 7, and 8).

The marrow aspirate smear and particle preparation were adequate for interpretation. The marrow biopsy, although somewhat small, was adequate for interpretation. The marrow was mildly hypercellular (60% cellularity, Figure 9). The majority of the cells (Table 3) were intermediate-sized blasts, many which had scant blue cytoplasm (on the Wright-stained aspirate smears) and slightly folded nuclei (Figures 10 & 11). Numerous dysplastic megakaryocytes were present in increased numbers with clusters and aggregates present on the biopsy (Figure 12) and included monolobate, binucleated, and small forms (Figures 13, 14 and 15). Erythroid maturation was slightly megaloblastoid with occasional dyserythropoietic forms present (Figure 16).

In an attempt to further classify the neoplastic cells present, cytochemical stains were performed on the bone marrow aspirate smear. The blasts were negative for sudan black (Figure 17), myeloperoxidase (Figure 18), chloroacetate esterase (Figure 19), and non-specific (alpha naphthyl acetate) esterase (Figure 20).

In light of the small population of blasts marking with CD61 on the flow cytometric immunophenotypic studies, an anti-CD61 immunostain was also performed on the bone marrow aspirate smear. Whereas the stain highlighted the cytoplasm of the numerous small and dysplastic megakaryocytes present (Figure 21), the blasts showed non-specific surface staining (Figure 22).

LABORATORY DATA:

Table 1. Complete Blood Cell Count*

  Patient Value Normal Range
WBC 5.1 10x9/L 4.5 - 11.0
RBC 2.44 10x12/L 4.35- 5.87
Hemoglobin 8.0 g/dl 13.3 - 17.7
Hematocrit 24.7% 40.0 - 52.0
MCV 101.2 fl 80.5 - 99.7
MCH 32.8 fl 28.2 - 32.2
MCHC 32.4 gm/dl 31.7 - 35.7
RDW 27.3% 11.5 - 15.0
PLT 353 10x9/L 150 - 450
*values were obtained post-packed red blood cell transfusions

Table 2. Peripheral Blood Differential

  Percentage Absolute Normal Range
Polys 13% 0.66 2.0-6.8
Bands 5% 0.26 0.1-0.8
Lymphs 40% 20.4 1.0-4.2
Atypical lymphs 4% 0.20 -
Monos 1% 0.05 0.1-0.8
Eos 1% 0.05 0.0-0.2
Blasts 36% 1.84 0.00-0.02

Table 3. Bone Marrow Differential*

  Patient Value (%) Adult Mean (%) Normal Range (%)
Blasts 74.0 1.0 0.0-2.0
Promyelocytes 0 3.0 2.0-4.0
Myelocytes 0.3 12.0 8.0-16.0
Metamyelocytes 0.3 17.0 10.0-25.0
Bands 1.3 12.0 9.0-18.0
PMN 1.7 9.0 7.0-14.0
Eosinophil Myelo/Meta 0 2.0 10.-4.0
Eosinophil Bands 0.3 1.0 0.0-3.0
Eosinophil Segs 0 1.0 1.0-2.0
Basophils 0.3 0.0 0.0-0.2
Monocytes 0.3 1.0 0.0-2.0
Pronormoblasts 0 1.0 0.0-1.0
Normoblasts 10.3 24.0 16.0-32.0
Lymphocytes 9.3 16.0 11.0-23.0
Plasma Cells 1.7 2.0 0.0-3.0
*total number of cells counted equaled 300

CYTOGENETICS

FINAL DIAGNOSIS


Case 

IndexCME Case StudiesFeedbackHome