Carbon monoxide poisoning, a diagnosis frequently overlooked.

Carbon monoxide (CO) is a common source of poisoning, yet the diagnosis is often overlooked. A study was undertaken to establish the true incidence of missed diagnosis and to assess retrospectively the effects of a campaign of public medical information on this subject. The wrong diagnoses reflected all the unusual clinical presentations that CO could produce. The high initial rate of wrong diagnoses (30% in 1975-1977) was reduced following the campaign (12% in 1978 and 5% in 1980) despite a considerable increase in the rate of admission to hospital of confirmed CO poisoning cases.