Plasmodium vivax Mimicking Morphologic Features of Plasmodium falciparum.

Plasmodium vivax (P. vivax) is the most common cause of malaria in Pakistan. Several cases of severe malaria due to P.vivax have been reported from Pakistan and India, however morphological characteristics of the parasite have been mainly ignored. We present two cases of P. vivax mono-infection, which were characterized by multiple infected red blood cells, similar to that seen in Plasmodium falciparum, as observed under microscopy. Both cases were confirmed as mono-infection of P.vivax on Giemsa stained thick and thin films, malaria rapid diagnostic test (RDT) and Polymerase Chain Reaction (PCR). Morphology on peripheral blood smear remains the gold standard for diagnosis of malaria and mimicking morphological features leads to misdiagnosis and mismanagement of patients.