Evaluation of MR-proANP and copeptin for sepsis diagnosis after burn injury

The significance of the validated biomarkers of sepsis Mid-regional pro-atrial natriuretic peptide (MR-proANP) and copeptin have not been tested in a burn injury setting.

42 consecutive patients were included in a prospective observational study. Daily blood specimens collected over the initial 20 days of treatment were quantitatively analysed by immunoluminometric sandwich assay (Kryptor, BRAHMS, Berlin, Germany) for MR-proANP, copeptin and procalcitonin (PCT).

In patients with absence of sepsis, copeptin levels initially increased post-burn injury and thereafter rapidly declined. In contrast, MR-proANP was only slightly elevated within the first few days. MR-proANP [199.8 (115.6; 399.5) vs 160.1 (93.7; 280.6), P < .007] and PCT [1.12 (0.32; 2.22) vs 0.32 (0.16; 0.53), P < .001] levels were significantly higher on days of sepsis. Copeptin, however, showed no significant differences [20.7 (11.8; 42.2) vs 16.8 (11.0; 30.6), P = .11]. Both, MR-proANP and PCT level increases were noted upon the first day of sepsis.

Burn injury itself maybe associated with copeptin and to a lesser degree MR-proANP level increases. Subsequent increases in MR-proANP may be considered diagnostic for sepsis but demonstrated no advantages over PCT. The role of copeptin remains inappropriate for diagnosing sepsis after burn injury (ClinicalTrials.gov number, NCT01055587).