Dr med. Peter Keller

Peter Keller

Dr med., FAMH Medizinische Mikrobiologie
Head of Mycobacteriology 
Deputy Head of Diagnostics

University of Bern
Institute for Infectious Diseases,


Peter Keller studied medicine from 2000-2006 in Zurich. He got his postgraduate education at the Institute of Medical Microbiology at the University of Zurich. From 2010-2014 he worked in Infectious Diseases and Internal Medicine at the University Hospital Jena (Germany). From 2015-2018 he was Deputy Head of the National Center for Mycobacteria in Zurich. Since 2019, he is Head of Innovation and Research at the Institute for Infectious Diseases at the University of Bern. His main research interests are applied clinical microbiology research with the introduction of laboratory automation into the routine microbiology laboratory, antimicrobial resistance and mycobacterial epidemiology.

Lecture: Routine implementation of fluorescence cytometry in the bacteriology laboratory

Microbiological workup of bacteriology samples involves microscopy and culture. For body fluids and especially for urines, fluorescence flow cytometry is recognized as rapid screening technology for infectious diseases. The talk will summarize published studies that investigated the diagnostic use of fluorescence cytometry in different workflows. It will review the diagnostic performance of the technology in comparison to the current standard-of-care comparators such as microscopy, biomarker assays and culture. Time-to-result and even more importantly, the clinical impact of the technology will be discussed. The main advantages of fluorescence technology are the accuracy and velocity of the measurement. In an outlook part, the talk will present novel research uses of fluorescence cytometry such as gram-typing of pathogens in blood culture bottles. The precision in the quantification of bacterial cells allows reducing the area of technical uncertainty in rapid antimicrobial susceptibility testing directly from positive blood cultures. Various body fluid such as joint punctuates, cerebrospinal fluid and ascites can be analysed by cytometers. The theoretical limits of detection and pilot diagnostic studies will be summarised for the most important body fluids.