Forum: Letter to the editor

Abstract

We have used bovine serum albumin in the preparation of peripheral blood smears and compared the morphology of leukocytes with smears prepared routinely without albumin. The albumin slides were prepared from a mixture of one drop of 22% albumin and 5 drops of EDTA-collected peripheral. Parallel evaluation of smears with and without albumin was performed on 72 cases of lymphoproliferative disorders, including chronic lymphocytic leukemia (nϭ38), chronic lymphocytic leukemia/prolymphocytic leukemia (nϭ9), splenic marginal zone lymphoma (nϭ7), chronic lymphocytic leukemia with Ritcher's transformation (nϭ6), mantle cell lymphoma (nϭ5), T cell prolymphocytic leukemia (nϭ3), large cell lymphoma (nϭ3), follicular lymphoma (nϭ1). Lymphoid cells were counted on each preparation and divided into four types of cells: small (10-15 micron), medium (15-20 micron), large (Ͼ20 micron), and smudged cells. The percentages of the four subtypes of cells on each preparation were compared. As shown in table 1, there were significant differences between the two preparations in each subtype of cells. As expected, the most conspicuous difference was in the number of smudged cells (table 1). Significant reduction in smudged cells was noted on the albumin preparation. Most importantly, the data suggests that there was a proportional decrease in smudged cells whether cells are considered small, medium, or large. Therefore the albumin preparation does not influence the relative ratio of cells in the four categories.In addition to marked decrease in smudge cells, we observed that in majority of patients with splenic marginal zone lymphoma, some of the lymphoid cells on the albumin preparation show marked irregularity in the nuclear contour and become floret shaped (See figure 1). This exaggeration of the folding and irregularity of nuclear contour was not conspicuous in other forms of chronic lymphoproliferative diseases. While the number of splenic marginal zone lymphoma examined here is small, this observation can be helpful and when observed additional diagnostic tests should be used to confirm or rule out the diagnosis of splenic marginal zone lymphoma.

Impact on canine neutrophil preservation with the addition of bovine serum albumin to K3‐EDTA whole blood samples

“…Variable ratios of BSA have been used in other studies, 12,15,16 including lower ratios of BSA to sample (1:12) 12 than the 1:5 ratio used in the present study. The feasibility of laboratories using BSA depends partially on ease of use and consideration of sample volume.…”

“…Similar morphologic changes consistent with cell deterioration are seen in blood samples from human patients with chronic lymphocytic leukemia or other lymphoproliferative diseases 12–14 . The addition of 22% bovine serum albumin (BSA) to K 3 ‐EDTA anticoagulated blood from these patients just prior to blood smear preparation reduces the number of disintegrated lymphocytes, as well as reduces overall cell and nuclear swelling of lymphocytes 12,14,15 . Different BSA‐to‐sample ratios with similar leukocyte preservative effects have been reported in human samples, including ratios of 1:5 15 and 1:12 12 .…”

“…The addition of 22% bovine serum albumin (BSA) to K 3 ‐EDTA anticoagulated blood from these patients just prior to blood smear preparation reduces the number of disintegrated lymphocytes, as well as reduces overall cell and nuclear swelling of lymphocytes 12,14,15 . Different BSA‐to‐sample ratios with similar leukocyte preservative effects have been reported in human samples, including ratios of 1:5 15 and 1:12 12 . In veterinary species, BSA added to reptile and murine blood prior to smear preparation reduces disintegrated cell numbers, 16,17 but has not been used to evaluate morphologic changes.…”