Brain natriuretic peptide plasma levels as a marker of prognosis in patients with community-acquired infection.

The aim of this study was to determine the role of the N-terminal prohormone form of BNP (NT-proBNP) in patients with acute community-acquired infection as a predictive marker and its correlation with the type of infection. We studied 42 patients with acute community-acquired infection. Levels of NT-proBNP were measured in all patients at hospital admission and on the third day, as well as in a control group of 84 healthy blood donors. NT-proBNP levels were markedly elevated in patients, 5897 versus 108 pg/ml in the control group (P=0.01) A positive association between the NT-proBNP levels and the final outcome of infection (P<0.0001) was found. Multivariate regression analysis identified NT-proBNP levels as the most important predictor of unfavorable outcome (P=0.017). Patients with lower respiratory tract infection had the maximum increase in NT-proBNP levels (P<0.048) and the most unfavorable outcome (P<0.03) regarding other sites of infection.

Brain natriuretic peptide increases in septic patients without severe sepsis or shock.

BACKGROUND: B-type natriuretic peptide (BNP) production increases in critically ill septic patients. We assessed the hypothesis that BNP is elevated in patients with community-acquired infections without severe sepsis or septic shock. METHODS: We studied 54 patients [20 males, median age 39 (interquartile range 23, 71)] without heart disease, persistent arrhythmias, or renal failure. BNP was measured in all patients at hospital admission and at pre-discharge and in a control group of 52 individuals. Myoglobin levels were also measured in septic patients. RESULTS: The infection was microbial in 40 patients, viral in 11, and of undefined etiology in 3. A systemic inflammatory response was evident in 38 patients on the initial evaluation. BNP on admission was higher in patients than in controls [25 (10, 82) pg/ml vs. 13 (5, 30) pg/ml, p=0.01] and it decreased to 16 (5, 47) pg/ml pre-discharge (p=0.0002). Multiple logistic regression identified the presence of microbial infection as the only independent predictor of an elevated BNP value on admission [adjusted odds ratio 9.8 (1.02-93.8), p=0.04]. In patients with microbial infection, location of infection in the lower respiratory tract and the presence of diabetes mellitus were independent predictors of the magnitude of BNP increase. Myoglobin was also increased on hospital admission 80 (37, 231) ng/ml and decreased pre-discharge to 59 (38, 94) ng/ml, p=0.004. Myoglobin level changes from admission to discharge were more prominent with increasing age and in females. CONCLUSION: BNP levels are elevated in the acute phase of community-acquired microbial infections without severe sepsis or septic shock.