Clinical and Genetic Aspects of Seizure Disorders Prevalent in an Isolated African Population

Abstract

Summary: In an isolated tribe in the interior of Tanzania the authors found that approximately 200 persons among an intake population of 10,000 persons presented at the bush clinic with kifafa, a convulsive seizure disorder that often leads to severe burns in those afflicted. Many of these patients showed parkinsonian symptoms and/or other neurological abnormalities and mental détérioration; there was high mortality. A frequent variant of the disease in children involved head nodding, which was often a precursor of later grand mal seizures. Transient psychotic episodes were seen in approximately 20% of all patients. The clinic patients were followed up to 10 years. The necessarily simple anticonvulsive treatment with phenobarbitone reduced the seizure frequency and intensity in the majority of cases. We shall discuss possible reasons for the high prevalence of seizure disorders in this tribe. Genetic factors appear to be of major importance and are reflected in the demonstrated high family incidence. Genetic analysis of the data does not support chromosomal, multifactorial, X‐linked, or autosomal‐dominant modes of inheritance. Analysis by the Li‐Mantel method indicates that the segregation ratios are compatible with a hypothesis of single autosomal‐recessive inheritance. Clinical and genetic data suggest that a hitherto unknown systemic disease of the central nervous system is highly prevalent in this isolated population. RÉSUMÉ Les auteurs décrivent une maladie convulsivante, le “kifafa” (mot swahili désignant cette affection), observée chez 200 sujets environ appartenant à une tribu isolée de la Tanzanie comportant 10.000 âmes; les porteurs de la maladie souffrent souvent de brulûres graves secondaires à des chutes dans les feux domestiques. Un grand nombre de ces malades ont des symptômes parkinsoniens et/ou d'autres anomalies neurologiques, ainsi qu'une détérioration men tale; le taux de mortalité est élevé. Une variante fréquemment observée chez L';enfant se manifeste sous forme de balancements de la téte qui constituent souvent un signe précurseur des crises de Grand Mai. Des épisodes psychotiques transitoires sont observés dans 20% des cas. Certains malades ont été suivis pendant 10 ans. Un traitement anticonvulsivant nécessairement simple (phénobarbital seul) réduit la fréquence et la gravité des crises chez la plupart des malades. Les auteurs discutent les diverses possibilityés pouvant expliquer L';importante prévalence de la maladie dans cette tribu. L';importance de facteurs génétiques est certaine et explique bien L';incidence familiale particulièrement élevée. L';analyse génétique n'est pas en faveur d'un mode de transmission multifactorial, liéà L';X ou dominant autosomique. Une étude par la méthode de Li‐Mantel montre que les rapports de ségrégation sont compatibles avec L';hypothése d'une hérédité de type récessif autosomique. Ces données cliniques et génétiques démontrent L';existence d'une maladie systémique du système nerveux central jusqu'ici méconnue; cette affection est extrêmement répandu...

Clinical and epidemiologic characteristics of nodding syndrome in Mundri County, southern Sudan

“…These episodes would occur several times each day, often during meals, and in some cases the illness progressed to generalized tonicclonic seizures, and to physical and mental deterioration. Similar head-nodding episodes, associated with physical and mental retardation and seizures, have been previously described in children in Uganda [1][2] , Tanzania [3][4] and Liberia 5 , and an association with onchocercias infection has been suggested. Our studies were the first to characterize Nodding Syndrome in southern Sudan.…”

Community-Based Study of Neurological Disorders in Rural Central Ethiopia

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