Browsing by Author "Onzivua, Sylvester"
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Item Histological examination of post-mortem brains of children with nodding syndrome(Annals of Translational Medicine, 2018) Hotterbeekx, An; Onzivua, Sylvester; Menon, Sonia; Colebunders, RobertWe read with interest the editorial by Boivin about the aetiology of nodding syndrome (1). In this paper the author mentions that histological examination of post-mortem brains of children with nodding syndrome revealed polarizable material which proved difficult to characterize or identify in the majority of specimens (1). We recently performed a post-mortem study on a person with nodding syndrome in Uganda but we did not observe polarized material in the brain. Moreover, these polarized crystal-like structures were not described on MRI scans of persons with nodding syndrome (2), suggesting that they appeared post mortem. Indeed, polarized material has been seen in brain tissue that was not processed in an appropriate way and these crystalized structures have been called Buscaino bodies, representing myelin altered by fixation and handling (3). This was most likely what happened with previous post-mortem studies performed in patients with nodding syndrome. During these studies the composition of the formaldehyde used in preserving these brains was not documented. Currently, in onchocerciasis endemic districts of northern Uganda, a state of the art post-mortem study is ongoing, investigating the histopathological abnormalities in the brains of persons with epilepsy, including nodding syndrome. Hopefully this study will help us to obtain a better understanding of how the Onchocerca volvulus parasite is able to cause epilepsy.Item Is nodding syndrome an Onchocerca volvulus induced neuro-inflammatory disorder? Uganda's story of research in understanding the disease(International Journal of Infectious Diseases, 2016) Idro, Richard; Opar, Bernard; Wamala, Joseph; Abbo, Catherine; Onzivua, Sylvester; Mwaka, Deogratius Amos; Kakooza-Mwesige, Angelina; Mbonye, Anthony; Aceng, Jane R.Nodding syndrome is a devastating neurological disorder, mostly affecting children in eastern Africa. An estimated 10 000 children are affected. Uganda, one of the most affected countries, set out to systematically investigate the disease and develop interventions for it. On December 21, 2015, the Ministry of Health held a meeting with community leaders from the affected areas to disseminate the results of the investigations made to date. This article summarizes the presentation and shares the story of studies into this peculiar disease. It also shares the results of preliminary studies on its pathogenesis and puts into perspective an upcoming treatment intervention. Clinical and electrophysiological studies have demonstrated nodding syndrome to be a complex epilepsy disorder. A definitive aetiological agent has not been established, but in agreement with other affected countries, a consistent epidemiological association has been demonstrated with infection by Onchocerca volvulus. Preliminary studies of its pathogenesis suggest that nodding syndrome may be a neuroinflammatory disorder, possibly induced by antibodies to O. volvulus cross-reacting with neuron proteins. Histological examination of post-mortem brains has shown some yet to be characterized polarizable material in the majority of specimens. Studies to confirm these observations and a clinical trial are planned for 2016.Item Is Nodding Syndrome an Onchocerca Volvulus-Induced Neuroinflammatory Disorder? Uganda’s Story of Research in Understanding the Disease(International Journal of Infectious Diseases, 2016) Idro, Richard; Opar, Bernard; Wamala, Joseph; Abbo, Catherine; Onzivua, Sylvester; Mwaka, Deogratius Amos; Kakooza-Mwesige, Angelina; Mbonye, Anthony; Aceng, Jane R.The Sustainable Development Goals (SDGs) mandate systematic monitoring of the health and wellbeing of all children to achieve optimal early childhood development. However, global epidemiological data on children with developmental disabilities are scarce. The Global Burden of Diseases, Injuries, and Risk Factors Study 2016 provides a comprehensive assessment of prevalence and years lived with disability (YLDs) for development disabilities among children younger than 5 years in 195 countries and territories from 1990 to 2016.Item Neuropathological Changes in Nakalanga Syndrome—A Case Report(Pathogens, 2021) Hotterbeekx, An; Lammens, Martin; Onzivua, Sylvester; Lukande, Robert; Olwa, Francis; Kumar-Singh, Samir; Hees, Stijn Van; Idro, Richard; Colebunders, RobertNakalanga syndrome is a clinical manifestation of onchocerciasis-associated epilepsy characterized by stunting, delayed or absent secondary sexual development and skeletal deformities, and is often accompanied by epileptic seizures. The pathophysiology of Nakalanga syndrome is unknown. Here, we describe the post-mortem findings of a 17-year-old female who died with Nakalanga syndrome in northern Uganda. Macroscopic and histopathological examination of all major organs (liver, lungs, kidney and heart), including the brain and the pituitary gland, was performed. The suspected cause of death was malaria, and all major organs and pituitary gland appeared normal, except the lungs, which were edematous consistent with the malaria. Neuropathological changes include signs of neuro-inflammation (gliosis and activated microglia), which co-localized with tau-reactive neurofibrillary tangles and threads. The pathology was most abundant in the frontal cortex, thalamic and hypothalamic regions, and mesencephalon. The choroid plexus showed psammoma bodies. These findings indicate accelerated aging, probably due to repeated seizures. The neuropathological findings were similar to other persons who died with onchocerciasis-associated epilepsy. Examination of the pituitary gland did not reveal new information concerning the underlying pathophysiological mechanism of Nakalanga syndrome. Therefore, more post-mortem studies should be performed.Item Nodding Syndrome in Uganda is aTauopathy(Acta neuropathologica, 2018) Pollanen, Michael S.; Onzivua, Sylvester; Robertson, Janice; McKeever, Paul M.; Olawa, Francis; Kitara, David L.; Fong, AmandaNodding syndrome is an epidemic neurologic disorder of unknown cause that affects children in the subsistence-farming communities of East Africa. We report the neuropathologic findings in five fatal cases (13–18 years of age at death) of nodding syndrome from the Acholi people in northern Uganda. Neuropathologic examination revealed tau-immunoreactive neuronal neurofibrillary tangles, pre-tangles, neuropil threads, and dot-like lesions involving the cerebral cortex, subcortical nuclei and brainstem. There was preferential involvement of the frontal and temporal lobes in a patchy distribution, mostly involving the crests of gyri and the superficial cortical lamina. The mesencephalopontine tegmental nuclei, substantia nigra, and locus coeruleus revealed globose neurofibrillary tangles and threads. We conclude that nodding syndrome is a tauopathy and may represent a newly recognized neurodegenerative disease.