Clostridium difficile: speeding up diagnosis

Despite best infection control efforts, hospitals remain the ideal environment for bacteria and viruses to thrive. Enclosed spaces, where a high proportion of the population is “at risk” and in close proximity, mean that infectious diseases spread easily from hand to hand and hand to surface. Since the start of the influenza pandemic, the Department of Health’s Catch It. Bin It. Kill It campaign has shifted advice from “clean your hands as soon as possible” in 2009 to “wash your hands with soap and water” in 2011. Patients and hospital visitors are increasingly well educated in the use of alcohol-based hand gels provided on wards. However, while this has helped to combat the spread of infections such as influenza and methicillin-resistant Staphylococcus aureus (MRSA), alcohol gels should not take the place of hand washing as only the physical action of rubbing the hands together removes Clostridium difficile spores from the hands. It is essential to prevent an upward creep in C. difficile infection (CDI) rates while attention is turned towards influenza. Patients infected with either pandemic influenza (H1N1) or CDI should be isolated, and, with facilities already stretched, the pressure is on to find the optimal test, treat and isolate strategy.

Correct patient for testing

The first step in the optimal CDI testing strategy is to ensure that the correct patients are selected for testing, and the right type of sample is collected. The Health Protection Agency (HPA) standard method and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guidelines advise that formed stools are unsuitable for the investigation of CDI. Any formed stool should be rejected and the appropriate comment appended to the report.1,2 The key feature of CDI is diarrhoea caused by C. difficile toxins. Without the toxins, there is no disease and thus no diarrhoea, so testing for C. difficile itself is unnecessary. Various risk factors are associated with CDI,3 including: