In a patient with cerebral malaria, which of the following asexual stage of Plasmodium falciparum can be seen on peripheral smear?
Ans. a (Trophozoites). (Ref. OP Ghai Paediatrics 6th ed. 245; Medical parasitology by DR Arora 2nd ed. 68, 75)# Schizonts are generally absent in peripheral smear of a patient with cerebral malaria.# P. falciparum differs from the other form of malarial parasites in that developing erythrocytic schizonts aggregate in capillaries of the brain and other internal organs, so that only young ring forms (early trophozoites) and gametocytes are typically found in PS of a patient with falciparum malaria.CharacteristicsFalciparumVivaxOvaleMalariaeAccole forms+---Duration of intrahepatic phase (days)5.58915Merozoites/infected hepatocytes30,00010,00015,00015,000Duration of erythrocyte cycle48485072Red cell preferenceYounger cellsRetiesRetiesBand formsMorphologyRing formsRing formsEnlargedTrophozoites Banana game tocytesEnlargedRBCsRBCs Schuffner dotSchuffner dotsmaurer's dotsJame's dotsPigment colorBlackYellowDark brownBlackAbility to cause relapseNoYesYesNoNephrotic SyndromeNoNoNoYes# Drugs which, attack exoerythrocytic stage (hypnozoites) given together with a clinical curative achieve total eradication of parasite from patient's body, known as radical cure.# A radical cure is needed in relapsing malaria (plasmodium vivax & ovale), while in Falciparum malaria, adequate treatment of clinical attack leaves no parasite in the body (there is no secondary exoerythrocytic tissue phase).- "Multiple rings":- "Accole" forms (early trophozoites):- "Reticulocytes" preferred by:- "Older RBCs" preferred by:P. falciparumP. falciparumP.vivaxP.malariae PLASMODIUM SPECIESSpeciesDiseaseImportant FeaturesBlood smearsLiver StagesTreatmentPlasmodium vivaxBenign tertian48-hour fever spikesEnlarged host cells; ameboid trophozoitesPersistent hypnozoites RelapseChloroquine PO4 then primaquinePlasmodium ovaleBenign tertian48-hour fever spikesOval, jagged, infected RBCsPersistent hypnozoites relapseChloroquine PO4 then primaquinePlasmodium malariaeQuartan or malarial72-hour fever spikes; recrudescenceBar and band forms; rosette schizontsNo persistent stageChloroquine PO4 (no radical cure necessary)Plasmodium falciparumMalignant tertianIrregular fever spikes; causes cerebral malariaMultiple ring forms crescent-shaped gametesNo persistent stageChloroquine resistance a problem
Tropozoites
Schizonts
Gametocytes
Hypnozoites
Infection