1. Department of Surgery, Franciscus Gasthuis and Vlietland, Rotterdam, the Netherlands.
2. Department of Clinical Microbiology, Leiden University Medical Center, Leiden, the Netherlands.
3. Department of Clinical Chemistry and Franciscus Gasthuis and Vlietland, Rotterdam, the Netherlands.
4. Department of Internal Medicine, Franciscus Gasthuis and Vlietland, Rotterdam, the Netherlands.