Resumo
Background: In the month of April 2015, an epidemic initially attributed to mysterious causes broke out in a rural community (Ode-Irele, Ondo State) of Nigeria. Twenty-five adults were affected, with a mortality of 18/25 (a rate of 72%). This is a report of laboratory analysis conducted at the College of Medicine, University of Ibadan, and the University College Hospital, Ibadan, Nigeria.
Methods: Samples of blood and urine (both coded A, B, and C) of the three victims of the disease, and three plastic containers of locally brewed alcoholic beverages (coded (D, E, F) reported to have been consumed by the victims were made available. All the samples were tested for copper, lead, zinc, and cadmium toxicity. The blood samples were tested for cholinesterase inhibition as an indirect test of probable pesticide poisoning. Methanol content of the samples was determined by gas chromatography.
Results: The urine and blood samples showed concentrations of lead, copper, zinc, and cadmium that were not uncommonly elevated. Zinc levels in the blood of two of the victims were low. There was a significant inhibition of cholinesterase activity in the three blood samples as follows; sample A 96.2%, sample B 31.8%, and sample C 2.5%. Methanol content of the alcoholic beverages ranged from 48 g/L (4.8%) to 625 g/L (62.5%), far above allowable limits of 0.005 g/L (0.0005%) in Nigeria.
Conclusions: Methanol poisoning was concluded to be the cause of the unknown disease. This finding guided measures that rapidly controlled and eventually ended the epidemic.
Keywords: Methanol poisoning, Heavy metals, Nigeria
Résumé
Contexte : Dans le mois d’avril 2015, une épidémie initialement attribuée à des causes mystérieuses s’est déclarée dans une communauté rurale (Ode-Irele, État d’Ondo) du Nigéria. Vingt-cinq adultes ont été touchés, avec une mortalité de 18/25 (un taux de 72%). Ceci s’agit d’un rapport d’analyse laboratoire réalisée au Collège de Médecine de l’Université d’Ibadan et au Collège Hospitalier Universitaire d’Ibadan au Nigéria.
Méthodes : Des échantillons de sang et d’urine (tous deux codés A, B et C) des trois victimes de la maladie et trois récipients en plastique de boissons alcoolisées brassées localement (codés (D, E, F) qui auraient été consommés par les victimes ont été soumis à des tests de toxicité sur le cuivre, le plomb, le zinc et le cadmium, ainsi que sur l’inhibition de la cholinestérase dans les échantillons de sang, en tant que test indirect d’intoxication probable par un pesticide. La teneur en méthanol des échantillons a été déterminée par chromatographie en phase gazeuse.
Résultats : Les échantillons d’urine et de sang ont montré des concentrations de plomb, de cuivre, de zinc et de cadmium qui n’étaient pas inhabituellement élevées. Les concentrations de zinc dans le sang de deux des victimes étaient faibles. Il y avait une inhibition significative de l’activité de la cholinestérase dans les trois échantillons de sang comme suit; échantillon A 96,2%, échantillon B 31,8% et échantillon C 2,5%. La teneur en méthanol des boissons alcoolisées variait de 48 g / L (4,8%) à 625 g / L (62,5%), bien au-dessus des limites autorisées de 0,005 g / L (0,0005%) au Nigéria.
Conclusions: il a été conclu que l’intoxication au méthanol était la cause de la maladie inconnue. Cette découverte a guidé les mesures qui ont rapidement maîtrisé et éventuellement mis fin à l’épidémie.
Mots clés: intoxication au méthanol, métaux lourds, Nigéria
Correspondence: Prof. O.G. Ademowo, Department of Pharmacology and Therapeutics, College of Medicine, University of Ibadan, Ibadan, Nigeria. Email: ademowo_g@yahoo.com
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