Procalcitonin levels should not guide CAP diagnosis, treatment

According to the researchers, the complex etiology of community-acquired pneumonia (CAP) makes disease management difficult. "In cases of bacterial pneumonia, initial antibiotic treatment is important for infection resolution, and a shorter time between diagnosis and treatment improves prognosis," Ishan S. Kamat, MD, MBA, internal medicine resident at Baylor College of Medicine, and colleagues wrote. Unlike manufacturer-proposed algorithms associating procalcitonin concentrations greater than 0.25 pg/L with bacterial infections, this analysis used a higher threshold of 0.5 pg/L, but noted consistently poor performance across a range of values. Because atypical bacteria are associated with lower procalcitonin concentrations than typical bacteria, including both may have reduced the performance of the test compared with differentiating viruses from typical bacteria only.