BRIEF REPORT: Incidence, Etiology, Risk Factors, and Outcome of Hospital-acquired Fever: A Systematic, Evidence-based Review

Temperature is universally measured in the hospitalized patient, but the literature on hospital-acquired fever has not been systematically reviewed. This systematic review is intended to provide clinicians with an overview of the incidence, etiology, and outcome of hospital-acquired fever. DATA SOURCES : We searched MEDLINE (1970 to 2005), EMBASE (1988 to 2004), and Web of Knowledge. References of all included articles were reviewed. Articles that focused on children, fever in the developing world, classic fever of unknown origin, or specialized patient populations were excluded. REVIEW METHODS : Articles were reviewed independently by 2 authors before inclusion; a third author acted as arbiter. RESULTS : Of over 1,000 studies reviewed, 7 met the criteria for inclusion. The incidence of hospital-acquired fever ranged from 2% to 17%. The etiology of fever was infection in 37% to 74%. Rates of antibiotic use for patients with a noninfectious cause of fever ranged from 29% to 55% for a mean duration of 6.6 to 9.6 days. Studies varied widely in their methodology and the patient population studied. CONCLUSIONS : Limited information is available to guide an evidence-based approach to hospital-acquired fever. We propose criteria to help standardize future studies of this important clinical situation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71660/1/j.1525-1497.2006.00566.x.pd

In Vivo pH Imaging with 99mTc-pHLIP

PURPOSE: A novel molecular imaging agent has been developed recently which stains tissues of low extracellular pH (pH (low) insertion peptide, pHLIP(®)). A pH-dependent process of peptide folding and insertion into cell membranes has been found in vitro. Targeting of acidic solid tumours has been demonstrated in vivo using fluorescence and PET labels. Here we present proof of feasibility studies of pHLIP with a SPECT label, (99m)Tc-AH114567, with focus on preclinical efficacy and imageability. PROCEDURES: LLC, LNCaP and PC-3 tumour xenografts were grown in mice and characterised by the angiogenesis marker (99m)Tc-NC100692 and by extracellular pH measurements with (31)P-MRS of 3-aminopropyl phosphonate. Biodistribution was assessed and CT/SPECT imaging performed. Oral administration of bicarbonate served as control. RESULTS AND CONCLUSION: (99m)Tc-AH114567 can be obtained via a robust synthesis with good radiolabelling profile and improved formulation. The tracer retains the pH-dependent ability to insert into membranes and to target tumours with similar pharmacokinetics and efficacy that had been demonstrated earlier for pHLIP with optical or (64)Cu PET labels. Despite the inherent challenges of SPECT compared to optical and PET imaging e.g. in terms of lower sensitivity, (99m)Tc-AH114567 shows adequate image quality and contrast. The main development need for transitioning SPECT labelled pHLIP into the clinic is more rapid background signal reduction which will be the focus of a subsequent optimization study