Serum Cortisol Predicts Death and Critical Disease

Serum Cortisol Predicts Death and Critical Disease

By Labmedica International staff writers
Posted on 12 Dec 2012

Several biomarkers and prognostic scores have been evaluated to predict prognosis in community-acquired pneumonia (CAP).

Serum cortisol concentration is associated with severity and mortality and predicts persistent clinical instability, making it a potential parameter to improve the identification of patients with high risk for a complicated disease course.

Scientists at the University Hospital Carl Gustav Carus (Dresden, Germany) studied 984 hospitalized CAP-patients and measured their serum cortisol concentrations and compared its prognostic accuracy to the leucocyte count, C-reactive protein levels, and the clinical prediction CRB-65 score. Serum cortisol was analyzed by a chemiluminescence immunoassay (Roche Diagnostics; Mannheim, Germany). This assay has a measurement range of 0.5 to 1,750 nmol/L; higher concentrations were analyzed by dilution of the serum sample.

Serum cortisol levels on admission were significantly higher in nonsurvivors at a median of 870 nmol/L when compared to survivors at 602 nmol/L. In patients with critical pneumonia the median was 972 nmol/L compared with a median 598 nmol/L in patients with noncritical pneumonia. In subgroup analyses, cortisol independently predicted critical pneumonia when compared to procalcitonin levels.

A causative microbiological pathogen was detected in 195 patients (20%). Of these, typical bacteria were found in 84 patients (43%), atypical bacteria in 64 (33%), viruses in 29 (15%) and mixed infection in 18 (9%). Streptococcus pneumoniae was the most frequently isolated pathogen and was found in 71 patients (36%).

The authors concluded that cortisol predicts mortality and critical disease in hospitalized CAP-patients independently of clinical scores and inflammatory biomarkers. They recommend that it should be incorporated into trials assessing optimal combinations of clinical criteria and biomarkers to improve initial high-risk prediction in CAP. The study was originally published in April 2012 in the Biomedical Central Journal BMC Infectious Diseases.

Related Links:
University Hospital Carl Gustav Carus
Roche Diagnostics