Procalcitonin and C-reactive protein as markers of bacterial infection in patients with solid tumours.

INTRODUCTION The diagnosis of bacterial infections in patients with solid tumours can be difficult as both the tumour and its treatment can cause symptoms and signs similar to those of infections. Many patients with solid tumours therefore receive antibiotic treatment without having a bacterial infection. In this prospective study, we wanted to investigate the value of procalcitonin (PCT) compared with C-reactive protein (CRP) as an indicator of bacterial infection in adult patients with solid tumours. METHODS A total of 41 patients with solid tumours admitted to hospital due to fever or clinical signs of infection had their PCT and CRP levels measured on and during admission. The patients were classified as having a microbio-logically verified infection, a radiologically verified infection or no infection. PCT and CRP were also measured in a control group of 34 out-patients with solid tumours, but with no signs of infection. RESULTS Of the 41 admitted patients, 25 were classified as having an infection (either microbiologically or radioo-gically verified). Among the 25 cases with infection, PCT was within the normal range in 11 cases and only elevated in 14. As nearly half of the patients with infection had PCT within the normal range, PCT is not suited to exclude an infection. CRP was elevated in 20 patients out of the 25. CONCLUSION PCT within the normal range cannot exclude an infection and does not appear to be superior to CRP to exclude an infection in patients with solid tumours. FUNDING not relevant. TRIAL REGISTRATION Clinicaltrials.Gov, NCT01227109.