Severe sepsis, defined

Systemic infections are those that have microorganisms (bacteria, viruses, yeasts, parasites) spread, usually via the bloodstream, beyond the portal of entry or original site of localized infection to multiple compartments of the body. When infections, either localized or systemic, are accompanied by signs and symptoms of a systemic inflammatory response (fever, rapid pulse, increase in white blood cells) the syndrome is called sepsis. Severe sepsis is defined by the additional occurrence of organ failure (either kidney, liver, brain, lungs), and is a potentially fatal condition (mortality around 50%). If there is hypotension not responding on fluid resuscitation it is called septic shock and the mortally is even higher (60-70%). 

Severe disease is defined as the presence of complications of colitis, such as sepsis, volume depletion, electrolyte imbalance, hypotension, paralytic ileus, and toxic megacolon. Patients with signs of severe disease should receive oral vancomycin as initial therapy. Surgical intervention may be indicated and lifesaving, particularly in cases complicated by toxic megacolon or colonic perforation. 

L7. Leithauser, B., Matthias, F. R Nicolai, U., and Voss, R., Hemostatic abnormalities and the severity of illness in patients at the onset of clinically defined sepsis. Intensive Care Med. 22, 631-636(1996). 

A UTI is defined as the presence of microorganisms in the urinary tract that caimot he accounted for hy contamination. The organisms present have the potential to invade the tissues of the urinary tract and adjacent structures. Infection may he limited to the growth of bacteria in the urine, which frequently may not produce symptoms. A UTI can present as several syndromes associated with an inflammatory response to microbial invasion and can range from asymptomatic bacteriuria to pyelonephritis with bacteremia or sepsis. 

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