Lipopolysaccharide-binding protein (LBP) and markers of acute-phase response in patients with multiple organ dysfunction syndrome (MODS) following open heart surgery

Cardiopulmonary bypass (CPB) is associated with an immunological injury tha t may cause pathophysiological alterations in the form of a systemic inflam matory response syndrome (SIRS) or a multiple organ dysfunction syndrome (M ODS). Previous studies on this issue have reported different changes of imm unological parameters during and after CPB, but there are no reports about the lipopolysaccharide-binding protein (LBP) in relationship to other marke rs of inflammation in patients with MODS following cardiovascular surgery. In the present study, we investigated the acute-phase response of patients with MODS of infectious and non-infectious origin following open-heart-surg ery. Plasma levels of procalcitonin (PCT), c-reactive protein (CRP), interl eukin-6 (IL-6), and LBP were measured in the first four postoperative days in 12 adult male patients with the signs of SIRS and two or more organ dysf unctions after myocardial revascularization (MODS-group), and 12 patients w ithout organ insufficiencies (SIRS-group). There were no significant differ ences regarding age, weight, height, preoperative NYHA-classification, preo perative LVEDP, or the number of anastomosis. Patients with MODS had a sign ificantly longer operation time, duration of ischemia, and duration of extr acorporeal circulation. None of the patients in the SIRS group died, wherea s in the MODS group, 4 patients died due to septic multiorgan failure. Plas ma PCT and IL-6 concentrations were significantly elevated in all MODS pati ents. CRP and LBP showed no differences between the MODS and the SIRS group . Comparing the MODS patients with and without positive microbial findings, we found significantly elevated levels of PCT and LBP in those patients wi th documented infections. Our results indicate that LBP may be a new marker for the differentiation between a severe non-infectious SIRS and an ongoin g bacterial sepsis in the early postoperative course following CPB, while a microbiological result Is still missing.