Natriuretic peptide proANP (1-98), a biomarker of ALI/ARDS in burns

Plasma atrial natriuretic peptide levels (proANP (1-98)), a parameter of myocardial dysfunction, have been reported to be increased in critically ill patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS). The aim of the study was to examine if proANP is a biomarker of ALI/ARDS as assessed by the Sequential Organ Failure Assessment score (SOFA Lung ≥2) in burn patients, and how it compares to the corresponding values for age, total body surface area percent (TBSA%) and inhalation injury for mortality prediction.

A group of 22 burn patients with a mean TBSA of 30% (10-75%) and a mean age of 52 years (25-84 years) was investigated during 2010. Organ dysfunction/failure was classified according to the SOFA score. The criteria for ALI/ARDS were based on SOFA Lung ≥2. ProANP (1-98) concentrations (nmoll(-1)) were measured by commercially available enzyme linked immunosorbent assay (ELISA) immunoassays (Biomedica Austria) on post-burn days 2 and 7.

ProANP levels on day 7 post-burn positively correlated with a SOFA score day 7 post-burn, c=0.91. The receiver operating curve (ROC) analysis proved a sensitivity of 75% and a specificity of 75% for ALI/ARDS at cut-off values >3.35 nmoll(-1). The ROC value of proANP for ALI/ARDS (SOFA Lung ≥2) was significantly larger than that of age, TBSA% and inhalation injury: 0.90, 0.71, 0.74, and 0.69 (p<0.001).

ProANP levels, as a biomarker of ALI/ARDS, in critically burn patients correlated with SOFA scoring. The inhalation injury did not lead to increase in proANP values.