Causes of fever and value of C-reactive protein and procalcitonin in differentiating infections from paraneoplastic fever.

Abstract
The aims of our retrospective study were to study first the causes of 245 febrile episodes in cancer patients and then the value of procalcitonin (PCT) and C-reactive protein (CRP) in differentiating infections from paraneoplastic fever. The causes of fever were studied in 245 consecutive cases observed between January and December 2002, and PCT and CRP diagnostic value in 155 cases (114 infections and 41 paraneoplastic fever). The two main causes of fever were infection (121 cases) and paraneoplastic fever (43 cases); 77 infections were microbiologically documented. Cocci gram positive caused 41 out of 77 documented infections. Paraneoplastic fever was more frequent in metastatic disease (p=6.10-6). CRP and PCT serum levels at admission did not differ significantly in the infection group and paraneoplastic fever group (respectively p=0.39 and p=0.14 with Mann-Whitney test). The PCT and CRP levels had poor prognostic value in infection (respectively 0.04 and 0.0003 with Mann-Whitney test). Causes of fever are very numerous in cancer patients (more than 75 different causes in this study). Bacterial infection is the most frequent cause. PCT and CRP failed to discriminate infection, but both had pejorative prognostic value in infected patients.