Impact of the Introduction of a Gastro-intestinal Panel by Polymerase Chain Reaction (PCR).

Gastrointestinal multiplex PCR panels have been introduced in clinical practice several years ago, but the impact on the management of patients is yet unknown. The investigators are interested to evaluate if the multiplex PCR panels introduced at the University Hospital of Lausanne in July 2017 modified the usual medical care and in particular the prescription of anti-infectious treatments. The high sensitivity of the multiplex PCR panels should allow a more precise diagnosis of the etiology of the gastrointestinal symptoms of the patients than the traditional methods of stool culture and microscopy. The investigators expect therefore to observe a modification of the proportion of patients receiving anti-infectious treatment, but it is uncertain if it will lead to an increase or a decrease in the use of antibiotics. On one hand antibiotics could be prescribed more often due to a greater and faster detection of enteropathogens. On the other hand antibiotics could be prescribed less often due to more precise diagnosis, showing that viruses and certain bacteria do not require antibiotic treatment.

Inclusion criteria

Ambulatory patients who consulted the University Hospital of Lausanne between July 2016 and May 2017, and were investigated by traditional methods (stool microscopy and culture).

Ambulatory patients who consulted the University Hospital of Lausanne between July 2017 and May 2018 and had stool investigations by a gastro-intestinal panel.

Exclusion criteria

Patients for whom there ia record in the file that they do not accept that their data are used for research purposes.