Monday, August 29, 2016

Case of the Week 411

This week's case was generously donated by Florida Fan. The patient is a young African adult male. Shown are Giemsa-stained thick and thin blood films.




Identification?

10 comments:

infectiologue said...

Intracellular rings, some with multiple infection per RBC. Some rings stuck to the side of the cell. I would favor Plasmodium falciparum infection.

Maran said...

Clearly a malaria (Plasmodium) infection. I can see nice ring stage parasites.

Shoog Saleh said...

It could be mixed infection of plasmodium Falciparum and Vivax since some of them contain one ring some 2

Anonymous said...

Multiply infected rbc's with appliqué forms = Plasmodium falciparum.
BW in Vt

boren said...

Plasmodium falciparum

Matthew Rollosson said...

West African or East African? It's relevant to the question of mixed P. falciparum/P. vivax infection.

Most West Africans are Duffy antigen negative.

William Sears said...

falciparum

Antonio Quispe said...

Clearly a Plasmodium infection, but hard to distinguish which species. Based on the red cell size, which seems to be larger I will say it is a vivax or ovale infection. Based on the schizonts could it be vivax (up to 16) or falciparum (up to 32) so it's hard to say. Based on the ring form, which seems to be fine with delicate double chromatin dots and applique form I will say is a falciparum ring form. So without knowing where the patient come from I will guess is most likely a vivax malaria infection, less likely a mixed vivax/falciparum infection, and remotely an ovale infection.

Arthur V said...

Present are multiple infected rbc's containing 1 or more ring form malaria parasites. The rbc's don't seem to be enlarged and the fact that there are multiple ring forms within single cells suggests p.falciparum. The ring forms are discrete with a tidy appearance and present with marginal forms. There appear to be no amoeboid ring forms, suggesting against P.vivax as the other species which presents with poly-infected cells, with exception of perhaps one form in the third image, though this is inconclusive since it could easily be a young trophozoite/slightly more mature ring form. The parasitaemia appears to be moderate judging by the number of ring forms present on the thick smear in image 1. The only other species of plasmodium which could present in this P.knowlesi, although it is absent from Africa so can likely be dismissed.

Given all this information, I see nothing here to suspect a vivax, ovale or malariae mixed infection. I am going to say it is a P.falciparum mono-infection.

Hans Naus said...

no erythrocytes are enlarged, no Schuffner dots multiple infections : Pl. falciparum