This article is more than 5 years old. Information may no longer be current.

Researchers find procalcitonin unreliable for acute liver failure

Procalcitonin concentrations were found to be an unreliable biomarker for detecting infection among patients with acute liver failure, mostly due to inflammation, according to published findings.

“In this study, we sought to determine whether [procalcitonin] would aid in the identification of infection in [acute liver failure] patients, since distinguishing sepsis from [acute liver failure] without infection has prognostic and therapeutic implications,” the researchers wrote.

Researchers analyzed data of 1,863 patients with acute liver failure (ALF) enrolled in the U.S. Acute Liver Failure Study between January 1998 and October 2010. This data was compared to data of 20 controls without any form of chronic liver disease. Serum samples and other clinical data were collected every day up to 7 consecutive days. The patients with ALF were divided into four groups: patients without systemic inflammatory response syndrome (SIRS; n = 628), patients with SIRS (n = 1,407), patients with severe sepsis (n = 387) and patients with septic shock (n = 31).

Once patients were divided into the SIRS categories, 115 were randomly selected based on data availability and their ALF and included in the final analysis.

Overall, 56 of the 155 patients with ALF and severe sepsis or septic shock tested positive for bacterial cultures. The chronic liver disease, non-SIRS, and SIRS groups had no reported positive cultures on or prior to the study day. Blood stream infections, with or without other positive cultures, were found in 23 of the 56 patients. A majority of the 23 patients had tracheal infections (n = 16), urinary tract infections (n = 8) or multiple without blood stream infections (n = 4), according to the research.

Procalcitonin (PCT) serum levels in a majority of the patient samples were high, with median values for all ALF groups near or above 2 ng/mL. This is the cut-off that “generally indicates severe sepsis,” the researchers wrote. PCT levels mildly increased with the presence of liver injury severity. However, there were no differences in PCT levels between the non-SIRS and SIRS groups — which had no documented infections — or the severe sepsis and septic shock groups that had recorded infections (P = .169).

PCT levels in patients with chronic liver disease differed from all ALF groups (P ≤ .001). The patients with acetaminophen toxicity had a median PCT level greater than 2 ng/mL, regardless of SIRS features, whereas some patients with positive cultures had PCT values less than 2 ng/mL. Many patients with PCT levels greater than 2 ng/mL did not show evidence of infection, according to the research.

The researchers concluded: “Procalcitonin detects bacterial infection and sepsis in the general population, but appears to be a more general marker of moderate to severe inflammation. As such, it has limited value as a single marker to discriminate between the presence or absence of bacterial infection in the setting of acute liver failure but may be of value in combination with other markers. … A prospective study with a larger sample size employing prospective determination of infection and standardized antibiotic usage might provide additional information regarding the relationship between PCT and severe liver injury, particularly [acetaminophen] toxicity.” – by Melinda Stevens

Disclosures: Siemens Healthcare Diagnostics provided instrumentation and reagents for the study. The researchers report no relevant financial disclosures relating to Siemens Healthcare Diagnostics.