Tests to Rapidly Diagnose Sepsis Essential
Diagnostic That Can Quickly Detect Infection Could Speed Treatment and Improve Outcome. Sepsis is a major healthcare problem. There are approximately 750,000 cases of sepsis each year in the U.S. and the number is growing.
Sepsis results from complex interactions between infecting microorganisms and host immune, inflammatory, and coagulation responses. Severe sepsis is defined as sepsis with organ dysfunction. Severe sepsis with hypotension, despite adequate fluid resuscitation, is septic shock. Septic shock and multiorgan dysfunction are the most common causes of death in sepsis patients. Mortality associated with severe sepsis remains unacceptably high—20 to 50%. When shock is present, mortality is even higher—40 to 60%.
Distinguishing patients with localized infections or a systemic inflammatory response (SIRS) from those with sepsis is challenging. SIRS is not specific to sepsis and can result from other conditions such as acute pancreatitis and immunodeficiencies. This makes a quick diagnosis, difficult.
Today, blood culture and culture techniques are the gold standard for detection of infection. Physicians order cultures as soon as two or more SIRS criteria are identified. The turnaround time for culture/blood culture is lengthy, ranging from 48 to 72 hours. As a result, antimicrobial therapy administration usually begins before culture results are available.
The choice of appropriate broad-spectrum antimicrobial therapy is tricky because of the rising prevalence of resistant pathogens. Today, this choice is left up to the physician’s intuition. Patients with severe sepsis or septic shock, however, have little margin for error in what therapy they receive. Consequently, there is a huge unmet need for fast turnaround tests that enable early administration of antimicrobial therapy/antibiotics by rapid identification of infection and facilitate choice of antimicrobial therapy through rapid identification and detection of causative pathogen.
Future sepsis diagnostic options include single-analyte immunoassays and molecular identification, for which opportunities exist at both the front and back ends.
Among all single-analyte biomarkers, detection of a protein biomarker called procalcitonin (PCT) in serum holds the most promise. Serum levels of PCT have been shown to increase in patients with an infection; high values will be seen in cases of severe sepsis and septic shock.