Carbonell, RaquelMoreno, GerardMartín-Loeches, IgnacioGomez-Bertomeu, FredericSarvisé, CarolinaGómez, JosepBodí, MaríaDíaz, EmiliPapiol, ElisabethTrefler, SandraNieto, MercedesEstella, AngelJiménez Herrera, MaríaVidal Cortés, PabloGuardiola, Juan JoséSolé-Violán, JordiRodríguez, Alejandro2025-01-072025-01-072021-03-262079-6382https://hdl.handle.net/10668/25062Background: Procalcitonin (PCT) and C-Reactive protein (CRP) are well-established sepsis biomarkers. The association of baseline PCT levels and mortality in pneumonia remains unclear, and we still do not know whether biomarkers levels could be related to the causative microorganism (GPC, GNB). The objective of this study is to address these issues. Methods: a retrospective observational cohort study was conducted in 184 Spanish ICUs (2009-2018). Results: 1608 patients with severe influenza pneumonia with PCT and CRP available levels on admission were included, 1186 with primary viral pneumonia (PVP) and 422 with bacterial Co-infection (BC). Those with BC presented higher PCT levels (4.25 [0.6-19.5] versus 0.6 [0.2-2.3]ng/mL) and CRP (36.7 [20.23-118] versus 28.05 [13.3-109]mg/dL) as compared to PVP (penAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/C-Reactive proteinGram negative bacilliGram-positive coccimortalitypneumoniaprocalcitoninresearch article33810263open access10.3390/antibiotics10040350PMC8066504https://www.mdpi.com/2079-6382/10/4/350/pdf?version=1617936902https://pmc.ncbi.nlm.nih.gov/articles/PMC8066504/pdf