The relationship between intoxication severity and blood interleukin 6, interleukin 10 and CRP levels in carbon monoxide-poisoned patients.

Carbon monoxide (CO) is one of the most common causes of death due to intoxications. No biochemical marker is available to evaluate the severity of CO intoxication. We measured high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and interleukin-10 (IL-10) levels in patients with different degrees of CO poisoning. We prospectively included 40 CO-poisoned patients admitted to emergency services. Blood samples were collected from the patients at admission (0 hour) and after treatment (six hours). While all patients received normobaric oxygen (NBO2) therapy, patients with severe CO poisoning received additional sessions of hyperbaric oxygen (HBO2) therapy. Blood samples were also collected from a group of healthy volunteers (n=40). Serum IL-6 and IL-10 levels were measured with the ELISA method while hs-CRP was quantified by turbidimetric analysis. At admission, IL-6 levels were significantly higher in the patient group compared to the control group (P=0.001), but IL-10 and hs-CRP levels were not significantly different between the groups. Compared to admission levels, IL-6 levels were higher at six hours (P=0.014). The patients were grouped according to treatment type (NBO2, HBO2) and history of syncope, but no significant differences were detected in patient subgroups regarding IL-6, IL-10 and hs-CRP levels. A weak positive correlation was found between COHb and lactate levels in patients (P=0.013; r=0.390).This study shows that IL-6 level increases in CO-poisoned patients, but it is not correlated with the severity of the intoxication.