The time course of body temperature, serum amyloid A protein, C-reactive protein and interleukin-6 in patients with bacterial infection during the initial 3 days of antibiotic therapy

The accuracy of using body temperature, serum amyloid A (SAA), C-reactive protein (CRP) and interleukin-6 (IL-6) in the work-up for early or late step-down therapy after an initial course of intravenous cefuroxime was investigated. Eighty-one hospitalized patients with an initial course of cefuroxime were retrospectively classified with one of the following diagnoses: bacterial infection without known focus, pneumonia, bronchitis, pyelonephritis, skin and soft-tissue infections or fever of other origin. The majority of the patients had sepsis (91% or 74/81) of whom 6 patients had severe sepsis. The inter-individual variability of body temperature, SAA, CRP and IL-6 was considerable. The time course of SAA and CRP during the first 24 h in patients with sepsis with a short duration of illness but without septic shock showed increasing levels during the initial course of intravenous therapy. In contrast, body temperature and IL-6 decreased, regardless of illness duration. Beyond 24 h, all 4 biomarkers declined, again regardless of the duration of illness. After the initial course of cefuroxime, biomarkers were non-distinguishing in terms of guidance in the judgement of early or late step-down therapy. Further studies are proposed for biomarker guidance antibiotic therapy in sepsis patients without septic shock.