Case #274 – April, 2010
A patient from Pakistan was admitted to a medical facility with non-cirrhosit portal hypertension, hepatic vein thrombosis, IVC stenosis and respiratory failure. No eosinophilia was reported at the time patient was admitted, but was present at 7% the next day. A blood smear was made at midnight and stained with Wright-Giemsa. Figure A shows what was observed by the attending pathologist at 1000x magnification. What is your diagnosis? Based on what criteria?
The objects in this case were artifacts (fungal elements, possibly Helicosporium sp. or related) and a diagnosis was made of No Parasites Found (NPF). Fungal hyphae and conidia are not uncommon airborne contaminants in the laboratory. If such objects were to alight on a drying blood smear, they could get stained, observed and possibly misinterpreted as parasites. In this case, the objects most-closely resembled a microfilaria. Careful examination of morphologic features, as well as accurate measurements, should be performed to ensure a proper diagnosis.
More on: Artifacts
Images presented in the DPDx case studies are from specimens submitted for diagnosis or archiving. On rare occasions, clinical histories given may be partly fictitious.
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