Foamy cell syndrome associated with repeated platelet transfusions

Area of Science:

• Hematology
• Immunology
• Pathology

Background:

• Patients undergoing repeated platelet transfusions can develop foamy cells in organs.
• Underlying conditions included aplastic anemia and chronic myelocytic leukemia, with some patients receiving bone marrow transplantation (BMT).

Observation:

• Foamy cells, identified as macrophages with foamy cytoplasm, were observed in multiple organs.
• These cells stained positive with Sudan black B and contained materials reactive to antihuman platelet antibody.
• Ultrastructural analysis revealed myelin-like substances within the foamy cells.

Findings:

• The foamy appearance is attributed to the incomplete intracellular degradation of phagocytosed platelets.
• Foamy cells observed in these patients resemble those found in idiopathic thrombocytopenic purpura.
• Opportunistic infections were noted in three of the four patients.

Implications:

• This finding provides insight into macrophage function following platelet transfusion.
• Understanding foamy cell formation may aid in managing complications associated with transfusion therapy.
• Further research could explore the clinical significance of these foamy cells in transfusion recipients.