Pro-adrenomedullin as a novel biomarker for predicting infections and response to antimicrobials in febrile patients with hematologic malignancies

Background. Health professionals and researchers have become increasingly interested in biomarkers that help them in diagnosis of infections with recent growing attention to procalcitonin (PCT) and pro-adrenomedullin (proADM). Methods. This study compares proADM to PCT as diagnostic and prognostic biomarkers of infection in febrile patients with hematologic malignancies (HMs). From June 2009 to December 2010, 340 febrile HM patients were evaluated for presence of sepsis, systemic inflammatory response syndrome (SIRS), documented infections, and response to antimicrobial therapy. Results. ProADM and PCT levels were measured at onset of fever and then on days 4-7 afterward. Of the 340 patients, 103 had definite sepsis, and 159 had SIRS. Only proADM initial levels were significantly higher in patients with localized bacterial infections than in those with no documented infection (P = .019) and in patients with definite sepsis than those with SIRS (P = .023). The initial proADM and PCT levels were significantly higher in neutropenic patients with BSIs than in those without documented infections (P = .010 and P = . 011, respectively). Follow-up, proADM, and PCT levels decreased significantly in response to antimicrobial therapy in patients with bacterial infections (BSIs or localized; P = .007 and P = .002, respectively). Conclusions. ProADM and PCT have promising roles in assisting clinicians in managing febrile HM patients. However, proADM appears to have the advantage of predicting localized bacterial infection and differentiating sepsis from SIRS.