SIRS, sepsis, and MODS

Abstract

For decades, a number of different terms, such as sepsis and septicaemia, derived from the ancient Greek term indicating putrefaction, have been used to indicate the clinical conditions associated with severe infections [1]. This lack of uniformity was due to extreme heterogeneity of the infection-related systemic signs and symptoms, ranging from mild fever to severe cardiovascular collapse. As a consequence, although every minimally experienced physician could distinguish between a moderately sick patient with pneumonia and a critically ill patient dying in septic shock, the intermediate degrees of severity were much less well defined. Further confusion was added by the desinence “–aemia”, derived from the Greek word indicating the blood; it was generally held that the presence of germs in the bloodstream was the only factor responsible for the disturbances involving the whole organism; only recently has it become clear that (1) these are primarily related to the interaction between the germs and the host’s immune system, leading to the production and the release of a host of mediators with either pro- or anti-inflammatory properties, and that (2) this process can occur everywhere in the body, and the resulting systemic disturbances are related to the spillover of these substances from the initial site of reaction [2].