Dimethylarginines in critically ill patients with severe sepsis or septic shock

Objective: We investigated the trend of asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in patients with severe sepsis and septic shock, and the relationship between dimethylarginines, organ failure, sepsis status and intensive care unit (ICU) mortality. Design: A prospective observational study carried out in three general adult Italian ICUs. Patients: Consecutive patients with severe sepsis or septic shock admitted to ICUs between December 2004 and March 2007. Methods: Plasma ADMA and SDMA were determined immediately after enrolment and on the third, sixth and twelfth days. Organ failure score, sepsis status, standard blood parameters and ICU outcome were collected. Results: Twenty-nine consecutive patients were enrolled. ADMA and SDMA were higher in patients than in healthy volunteers. Sixteen patients who suffered from septic shock during ICU stay had a higher average value of daily ADMA and SDMA. ADMA was significantly related to arterial pH. SDMA was related to diabetes mellitus, Simplified Acute Physiology Score II, arterial pH level, daily Sequential Organ Failure Assessment score, and creatinine. Independent variables predicting ICU mortality were Simplified Acute Physiology Score II, mean Sequential Organ Failure Assessment score, and SDMA. Conclusion: Dimethylarginines are not only markers of body catabolism but may have a high metabolic activity, tightly related to the risk of adverse outcome of sepsis syndrome.