A researcher in Montreal reported that treating community-acquired pneumonia with a biomarker might not always yield positive results. Pneumonia patients with low levels of the protein procalcitonin and treated according to the protocol had higher-than-expected relapse chances. The findings are shocking because treating patients with procalcitonin, a soluble protein that plays a role in the response to severe systemic inflammation and in particular is a marker of bacterial infections, has been shown to reduce the use of antibiotics with no increase in mortality.
The current suggestion is that antibacterial treatment can be adjusted based on procalcitonin levels in patients with sepsis, as studies have proven that low levels of the protein mean antibiotic doses can be reduced without an increased risk of death. Pneumonia patients with procalcitonin of at least 0.25 nanograms per milliliter should complete a five-day course of antibiotics no matter what. However, antibiotics could be stopped if the level was below 0.25 nanograms per milliliter. Reference: http://www.medpagetoday.com/MeetingCoverage/CHEST/54306