[The role of procalcitonin in the differential diagnosis of fever in patiens with multiple myeloma].

Fever and elevated C-reactive protein are frequently found in hematooncological patients. It is sometimes difficult to distinguish between infectious fever and drug-related or tumour-associated fever. Tumour-related fever is not very common in multiple myeloma (unlike malignant lymphomas). C-reactive protein (CRP) is usually elevated simultaneously with fever and so it cannot be used in differential diagnosis of febrile states. There is another marker that provides information about the origins of the fever--rocalcitonin. We present cases of three patients that illustrate the significance of procalcitonin in patients with multiple myeloma.