Abstract
BACKGROUND: Malaria in pregnancy can cause fatal complications by parasite sequestration mechanism, which can cause monocyte infiltration in the intervillous space. P. vivax infection was significantly associated with malaria pigment in the placenta, indicating past subclinical infections. OBJECTIVE: This study aimed to determine the mechanism of P. vivax in the pathogenesis of placental malaria and its relationship with LBW. METHODS: This study was observational analytic with a cross-sectional approach. Placental tissue samples were obtained from pregnant women with LBW babies during delivery in Maumere, Nusa Tenggara Timur. The samples used in this study were confirmed by a polymerase chain reaction and consisted of 25 samples with 12 positive and 13 negative samples. Placental tissue samples were made with Hematoxylin-Eosin staining and observed under 1000x magnification at 100 fields using a light microscope. Parasite density, monocyte infiltration, and parasite pigments deposition were calculated. RESULTS: Microscopic observation revealed that there was a significant difference in infected erythrocytes sequestration between groups. Interestingly, monocyte and malaria pigments accumulation were found in malaria-positive and -negative groups, and no significant difference between groups. The correlation test showed no significant relationship between monocyte infiltration and LBW in the malaria-positive and -negative group and between parasite pigments and LBW in both groups. Moreover, there was no significant correlation between parasite density and LBW in the positive and negative groups. CONCLUSION: P. vivax infection causes acute, sub-acute, and chronic placental malaria in subclinical infected pregnant women in Maumere, Nusa Tenggara Timur that might cause an LBW baby.