Aspects cliniques et neuroradiologiques de l'intoxication aiguë au CO

Carbon monoxide poisoning (CO) is a common but often unrecognized cause of acute toxic encephalopathy. Characteristic anomalies on magnetic resonance imaging contribute greatly to positive diagnosis. We report the case of a 47-year-old woman, admitted for accidental acute carbon monoxide poisoning. At admission, the patient was conscious and exhibited major anxiety with generalized akinesia and rigidity. The brain MRI showed typically symmetrical bilateral hypersignals from the pallidums and the loci niger. Normal pressure oxygen therapy was administered associated with symptomatic treatment (L-dopa, peribedil, piracetam, anxiolytic and antidepressor drugs). Motor function remained stationary while the thymic component improved. Typical parkinosism is rarely observed during CO poisoning. Neuro-imaging (computed tomography, brain MRI) is however very specific, showing abnormal signals bilaterally from the basal ganglia.