Sepsis under siege

Abstract

The understanding of severe sepsis and septic shock could be on the verge of a breakthrough, in view of research overturning the long-held belief that the conditions are caused only by Gram-negative bacterial infections. The implications—and potential treatments—could be huge, as severe sepsis and septic shock affect 3 people in every 1,000 and kill at least 135,000 Europeans each year, about the same number of deaths caused by lung cancer. Treatment costs currently amount to about €7.6 billion in the EU alone, and existing therapies are able to save only a relatively small number of patients suffering from septic shock. Furthermore, the number of severe sepsis cases—over half of which end in death—is increasing at a rate of 1.5% per year as the number of immunocompromised people increases and the population ages. Yet, despite these grim statistics, sepsis receives far less attention and media coverage than do other big killers, such as heart disease and cancer. This might be partly because severe sepsis is not really a disease, but rather a syndrome describing a systemic response. Invading pathogens release endotoxins into the bloodstream, which, in turn, activate various immunological and coagulatory responses that can go awry, leading to sepsis and septic shock. However, current research on the first stages of this immune response has led some researchers to propose that, in rare cases, sepsis can occur without an acute infection and in the absence of endotoxins.