Case #403 – September 2015

A 25-year-old male presented to the ER with complaints of dizziness, headache, ear pain, fever, chills, and malaise approximately one week after returning from a missionary trip to Ghana. The patient claims to have been compliant with anti-malarial prophylaxis. A blood specimen was collected in EDTA and sent to the Hematology lab for processing. While admitted at the hospital, he developed thrombocytopenia, reticulocytosis, and hyperbilirubinemia. Figures A and B show what was observed on a thick blood film stained with Wright stain; figures C and D show what was observed on a thin blood film stained with Wright stain. What is your diagnosis? Based on what criteria?

Figure A

Figure B

Figure C

Figure D

This was a case of severe malaria caused by Plasmodium falciparum. Diagnostic morphologic features included:

normal-sized infected red blood cells (RBCs).
ring-form trophozoites with thin, delicate cytoplasm and (occasionally) double chromatin dots.
multiply-infected RBCs.
appliqué forms.
a high parasitemia lacking other stages.
presence of pigment (which ruled-out Babesia sp.)