Placental Malaria in Colombia: Histopathologic Findings in Plasmodium vivax and P. falciparum Infections

Abstract

Abstract. Studies on gestational malaria and placental malaria have been scarce in malaria-endemic areas of the Western Hemisphere. To describe the histopathology of placental malaria in Colombia, a longitudinal descriptive study was conducted. In this study, 179 placentas were studied by histologic analysis (112 with gestational malaria and 67 negative for malaria). Placental malaria was confirmed in 22.35%, 50.0% had previous infections, and 47.5% had acute infections. Typical malaria-associated changes were observed in 37%. The most common changes were villitis, intervillitis, deciduitis, increased fibrin deposition, increased syncytial knots, mononuclear (monocytes/macrophages and lymphocytes), polymorphonuclear cell infiltration, and trophozoites in fetal erythrocytes. No association was found between type of placental changes observed and histopathologic classification of placental malaria. The findings are consistent with those reported for placental malaria in other regions. Plasmodium vivax was the main parasite responsible for placental and gestational malaria, but its role in the pathogenesis of placental malaria was not conclusive.

Immune responses during gestational malaria: a review of the current knowledge and future trend of research

“…Recent reports supported the concept that detection and treatment of pregnant malaria during early gestation prevents miscarriage both in P. vivax and P. falciparum infections [31,43]. At delivery, placental infection by P. vivax has been confirmed both in cases from America and Asia [35,[45][46][47].…”

“…The presence of placental infection does not always result in placental pathology and vice versa [47]. This means that resolved infections can leave sequelae in the placenta and significant parasitaemia or a chronic-persistent placental invasion are required to evidence the effect in this tissue.…”

“…Being both, Dengue virus and Plasmodium spp., important pro-inflammatory agents, their effects in a pregnant host probably superimpose and result in greater morbidity and mortality. Both in Africa and in America, co-infection with other pathogens, different from HIV, is rarely addressed, and recent reports of high frequency of histology alterations in non-malaria affected placentas, indicate that this is a field worthwhile to study [47].…”

“…However, in most field settings, laboratory conditions and personnel are limited and made unpractical this approach. Similarly, examination of the placenta by histology, which has proved suitable to diagnose past and current infection [47,135], is unpractical due to the need for specialized personnel and technical requirements.…”

From within host dynamics to the epidemiology of infectious disease: Scientific overview and challenges

“…They asexually replicate for about 24 to 72 hours, depending on the species, which results in eight to 32 newly formed merozoites per each infected erythrocyte. Upon maturation, the parasites are released from the infected RBCs and immediately begin the process of infecting other available RBCs in circulation and possibly in some tissue compartments; again, many of the specific details are yet to be discovered [30; 66; 67; 68]. All clinical symptoms of malaria occur as the parasites are being released from the host RBCs along with the cell's contents at this mature stage of development, which include remnant membranous materials, proteins, lipids, nucleic acids, and various unknown metabolites.…”