This study investigates the ultrastructural features of parasitized erythrocyte (PRBC) sequestration in cerebral malaria (CM) and non-cerebral malaria (NCM) patients. Postmortem samples from patients with P. falciparum malaria were examined using electron microscopy. The results showed that the proportion of PRBCs in cerebral vessels was significantly higher in CM patients compared to NCM patients, and also higher in the brain than in other organs. CM patients had more tightly packed RBCs in cerebral vessels, but there was no significant difference in endothelial damage or the presence of endothelial pseudopodia. No thrombosis or acute/chronic inflammation was observed, and no immune complex deposits were found in cerebral vessels. Parasites in cerebral vessels were mainly trophozoites or schizonts, with occasional RBC remnants. PRBCs adhered to endothelium via surface knobs, and no evidence of inflammatory or immune pathogenesis was found. The clinical effects were likely due to anoxia and parasite metabolic activities. Ultrastructural analysis revealed that PRBCs in CM patients had irregular shapes, with surface knobs and cytoplasmic changes. The plasma membrane of PRBCs showed surface irregularities, and some membranes were fenestrated. The cytoplasm of parasitized cells was less electron-dense than normal RBCs, with granular appearance. PRBCs were found in capillaries and venules, with some showing degenerative changes. The presence of PRBCs in cerebral vessels was associated with tight packing, but not with endothelial damage. The study also found that PRBCs in the skin were more accurately represented by skin smears than peripheral blood smears. The study concluded that there is no evidence of inflammatory or immune pathogenesis in human cerebral malaria, and that the clinical effects are likely due to anoxia and parasite metabolic activities. The selective adhesion of PRBCs to cerebral endothelium is the most probable explanation for the high degree of red cell parasitization in cerebral capillaries. The presence of endothelial pseudopodia may contribute to the selective accumulation of PRBCs in the brain. The study also suggests that the clinical features of CM may be explained by mechanical obstruction of cerebral vessels by PRBCs, rather than immune or inflammatory processes. The findings contrast with those seen in some rodent malarias, where monocyte accumulation is a feature of the disease. The study highlights the importance of ultrastructural analysis in understanding the pathogenesis of cerebral malaria.This study investigates the ultrastructural features of parasitized erythrocyte (PRBC) sequestration in cerebral malaria (CM) and non-cerebral malaria (NCM) patients. Postmortem samples from patients with P. falciparum malaria were examined using electron microscopy. The results showed that the proportion of PRBCs in cerebral vessels was significantly higher in CM patients compared to NCM patients, and also higher in the brain than in other organs. CM patients had more tightly packed RBCs in cerebral vessels, but there was no significant difference in endothelial damage or the presence of endothelial pseudopodia. No thrombosis or acute/chronic inflammation was observed, and no immune complex deposits were found in cerebral vessels. Parasites in cerebral vessels were mainly trophozoites or schizonts, with occasional RBC remnants. PRBCs adhered to endothelium via surface knobs, and no evidence of inflammatory or immune pathogenesis was found. The clinical effects were likely due to anoxia and parasite metabolic activities. Ultrastructural analysis revealed that PRBCs in CM patients had irregular shapes, with surface knobs and cytoplasmic changes. The plasma membrane of PRBCs showed surface irregularities, and some membranes were fenestrated. The cytoplasm of parasitized cells was less electron-dense than normal RBCs, with granular appearance. PRBCs were found in capillaries and venules, with some showing degenerative changes. The presence of PRBCs in cerebral vessels was associated with tight packing, but not with endothelial damage. The study also found that PRBCs in the skin were more accurately represented by skin smears than peripheral blood smears. The study concluded that there is no evidence of inflammatory or immune pathogenesis in human cerebral malaria, and that the clinical effects are likely due to anoxia and parasite metabolic activities. The selective adhesion of PRBCs to cerebral endothelium is the most probable explanation for the high degree of red cell parasitization in cerebral capillaries. The presence of endothelial pseudopodia may contribute to the selective accumulation of PRBCs in the brain. The study also suggests that the clinical features of CM may be explained by mechanical obstruction of cerebral vessels by PRBCs, rather than immune or inflammatory processes. The findings contrast with those seen in some rodent malarias, where monocyte accumulation is a feature of the disease. The study highlights the importance of ultrastructural analysis in understanding the pathogenesis of cerebral malaria.