The value of histopathology of the placenta in a tertiary referral hospital in South Africa

CITATION: Malusi, Z., et al. 2019. The value of histopathology of the placenta in a tertiary referral hospital in South Africa. South African Journal of Obstetrics and Gynaecology, 25(2):64-67, doi:10.7196/sajog.1434.The original publication is available at http://www.sajog.org.zaBackground. Unexplained intrauterine death (IUD) remains the most common cause of perinatal death in babies of <1 000 g in South Africa (SA). Information from examination of the placenta subsequent to an adverse perinatal outcome is often underutilised and placental histology can contribute to determining the cause of perinatal death and other adverse outcomes in many instances.  Objectives. To correlate placental histopathology with the clinical indication for submission and to demonstrate the value of placental histopathology in understanding adverse perinatal outcomes.  Methods. We reviewed 2 years’ singleton placental histology reports at a tertiary academic hospital in the Western Cape, SA. All samples were from placentas of >24 weeks’ gestation.  Results. The total sample (N=822) comprised 60.9% live-birth placentas and 39.1% IUD placentas. In the IUD group, the cause of death was clinically unexplained in 55.9% of cases. Histopathology identified in this group included chorioamnionitis (CA) (34.5%), maternal vascular malperfusion (32.1%), abruptio placentae (31.5%), delayed villous maturation (17.8%) and toxoplasmosis, other agents, rubella, cytomegalovirus and herpes simplex (TORCH) infections (6.1%), most commonly syphilis. No pathology was found in only 2% of IUD cases. Among live births, preterm labour accounted for 41.9% of placental submissions, of which the cause was unknown in 46.2% of cases. Clinically indicated and histologically defined CA was poorly correlated.  Conclusion. This study demonstrates the value of placental histopathology in cases of adverse perinatal outcome.http://www.sajog.org.za/index.php/sajog/article/view/1434Publisher's versio

Influence of temperature on the interaction for resource utilization between fall armyworm, Spodoptera frugiperda (Lepidoptera : Noctuidae), and a community of lepidopteran maize stemborers Larvae

Intra- and interspecific interactions within communities of species that utilize the same resources are characterized by competition or facilitation. The noctuid stemborers, Busseola fusca and Sesamia calamistis, and the crambid stemborer, Chilo partellus were the most important pests of maize in sub-Saharan Africa before the recent "invasion" of fall armyworm (FAW), Spodoptera frugiperda, which currently seriously limits maize yields in Africa. This new pest is interacting with the stemborer community at the larval stage in the use of maize resources. From previous works on the influence of temperature on the larval intra- and interspecific resources utilization within the community of Lepidoptera stemborers involving B. fusca, S. calamistis, and C. partellus, there is a need to update these studies by adding the new pest, S. frugiperda, in order to understand the effect of temperature on the larval interactions of all these four species under the context of climate change. The influence of temperature on intra- and interspecific larval interactions was studied using artificial stems kept at different constant temperatures (15 degrees C, 20 degrees C, 25 degrees C, and 30 degrees C) in an incubator and assessing survival and relative growth rates of each species in single and multi-species experiments. After the inclusion of FAW into the experiments, with regard to relative growth rates, both intra- and interspecific competition was observed among all four species. With regard to survival rates, cannibalism can also explain the intra- and interspecific interactions observed among all four species. Interspecific competition was stronger between the stemborers than between the FAW and the stemborers. Similar to lepidopteran stemborers, temperature affected both survival and relative growth rates of the FAW as well. Regardless of the temperature, C. partellus was superior in interspecific interactions shown by higher relative growth and survival rates. The results suggest that the FAW will co-exist with stemborer species along entire temperature gradient, though competition and/or cannibalism with them is weak. In addition, temperature increases caused by climate change is likely to confer an advantage to C. partellus over the fall armyworm and the other noctuids