The diagnostic and prognostic value of mature and total adrenomedullin for sepsis: a prospective observational study

Introduction
Information about biologically active adrenomedullin (mature AM), a potential new biomarker for sepsis and septic shock, is limited. Here, we investigated the value of mature AM for diagnosis and outcome prediction in sepsis.

Material and methods
Patients admitted to the intensive care unit (ICU) were retrospectively cate­gorised into non-sepsis or sepsis groups, according to the Sepsis-3 definitions. Plasma levels of mature and total (the sum of the levels of intermediate and mature forms) AM were measured, and their usefulness was compared with that of other sepsis biomarkers, such as procalcitonin and presepsin.

Results
Of the 98 patients analysed, 42 were assigned to the non-sepsis and 56 to the sepsis group. Mature and total AM levels on admission were significantly higher in patients with than in those without sepsis. The areas under the receiver operating characteristic curves (AUCs) of mature and total AM for diagnosing sepsis were 0.85 and 0.88, whereas those of procalcitonin and presepsin were 0.83 and 0.68, respectively. AUCs of mature and total AM for predicting 28-day mortality in patients with sepsis became significant on day 3 after admission. A good correlation between the AM forms was found, indicating that changes in their plasma levels may directly reflect each other.

Conclusions
Because mature and total AM levels increased significantly in patients with sepsis on admission, both forms may be used as reliable and early biomarkers for diagnosing sepsis according to the Sepsis-3 definitions. However, prediction of 28-day mortality in such patients would require several days of ICU stay.