A 30-year-old man presenting with high-grade fever every 72 hours (quartan pattern), splenomegaly, and haemolytic anaemia has a peripheral smear showing infected RBCs of normal or slightly smaller size, band-form trophozoites, and occasional 'rosette' segmented schizonts (6–12 merozoites arranged around a central pigment mass). What is the species and a key clinical concern in this patient?

• A Plasmodium malariae — quartan malaria associated with malarial nephrotic syndrome (P. malariae nephropathy) in chronic infections ✓
• B Plasmodium falciparum — malignant tertian malaria with cerebral malaria risk
• C Plasmodium vivax — benign tertian with Schüffner's dots and risk of splenic rupture
• D Plasmodium ovale — mild quartan pattern, rare in India

Explanation

P. malariae causes quartan malaria (fever every 72 hours). The peripheral smear shows: band (rectangular) forms in RBCs of normal/smaller size, 'daisy-head' rosette schizonts (6–12 merozoites around central pigment), and absent Schüffner's dots. Chronic P. malariae infection in children is uniquely associated with immune complex-mediated glomerulonephritis leading to nephrotic syndrome (malarial nephropathy — Type III hypersensitivity, IgM-IgG complexes depositing in glomerular basement membrane). P. vivax/ovale show Schüffner's dots; P. falciparum shows irregular ring forms and banana-shaped gametocytes.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.