1/For the path residents taking CP call for the first time this month, I thought I’d post a short series on things to look out for when you get called to look at a blood smear. First up: pancytopenia. #hemepath
2/It’s not always possible to determine the cause of pancytopenia based on blood smear morphology alone. However, here is a (not comprehensive) list of clues you don’t want to miss: 
3/Leukoerythroblastic features (presence of nRBCs and granulocyte precursors). Raises concern for bone marrow infiltration (by fibrosis, metastatic or hematologic tumors), especially if teardrop cells are present.
4/Is the patient immunosuppressed? Don’t forget to look for organisms! This is a case of disseminated histoplasmosis in an immunocompromised patient.
5/Look closely for dysplastic granulocytes, especially if the MCV is high.
6/Don’t forget that megaloblastic anemia can actually present with pancytopenia. Look closely for hypersegmented neutrophils, especially if the MCV is high.
7/Remember that larger cells can be pushed to the periphery of the slide. Check the smear edges to look for rare atypical cells. In this case of acute promyelocytic leukemia, the blasts were rare and only present at the edges of the smear.
