Clinical outcome and magnetic resonance imaging of carbon monoxide intoxication. A long-term follow-up study.
The clinical and neuroradiological outcome of carbon monoxide (CO) intoxication was evaluated prospectively in 30 patients over a follow-up period of 3 years. Among the patients studied, 22 had been acutely exposed to CO while 8 were chronically exposed. One month after CO poisoning, 12 of the 22 patients with acute intoxication showed magnetic resonance imaging (MRI) abnormalities: 6 also had neurological sequelae and 6 were asymptomatic. The remaining 10 patients showed neither MRI abnormalities nor neurological sequelae. During the 3-year follow-up, 4 of the patients with both MRI abnormalities and neurological sequelae improved in both clinical features and MRI findings. One of the 6 asymptomatic patients with MRI abnormalities developed a progressive cognitive impairment 2 months after acute intoxication, with a concomitant severe worsening of the MRI lesions. Among the 10 patients with neither MRI abnormalities nor neurological sequelae, only 1 developed neurological sequelae after a clear period of 4 months. In the group of patients who experienced chronic CO intoxication, only 1 presented with a neuropsychiatric syndrome which improved at follow-up. Brain MRI showed white matter lesions which remained unchanged at control scan after 1 year. In conclusion, we observed that some patients with severe CO poisoning and neurological sequelae may fully regain normal functions after approximately 1 year. The presence of MRI lesions 1 month after CO poisoning did not accurately predict the subsequent outcome. The observation of a clear period longer than the usual 2-40 day interval in 2 patients should be considered for careful planning of follow-up and for prognosis in CO-poisoned patients.
Pavese
N
N
Department of Neurosciences, Section of Neurology, University of Pisa, Italy.
Napolitano
A
A
De Iaco
G
G
Canapicchi
R
R
Collavoli
P L
PL
Lucetti
C
C
Gambaccini
G
G
Bonuccelli
U
U
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology*; D002249:Carbon Monoxide Poisoning / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D002648:Child; D002908:Chronic Disease; D003072:Cognition Disorders / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D001523:Mental Disorders / Q000209:etiology; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology; D020127:Recovery of Function