A dramatic increase in the frequency and in severity of nosocomial Clostridium difficile-associated disease has been noted worldwide. In addition, a new and hypervirulent clone has emerged, causing large outbreaks in many countries. This article summarises the recommendations on infection control measures from the European Center for Disease Prevention and Control (ECDC).
by Dr Ralf-Peter Vonberg
Microbiological background: 30 years of antibiotic-associated diarrhoea
Clostridium difficile (CD) is an anaerobic, spore-forming, gram-positive rod bacterium. It is part of the physiological gut flora in about 20% of humans, and some CD strains are capable of producing enterotoxins (e.g., toxins A and B).
CD was first described in 1978 as the cause of intestinal diseases following antimicrobial therapy. Meanwhile, various antibiotic substances have been identified as risk factors for the occurrence of C. difficile-associated disease (CDAD), for example clindamycin, broad spectrum cephalosporins, and fluoroquinolones. Most patients affected by CDAD will only develop rather mild diarrhoea. However, more severe courses of disease, ending up in pseudo membranous colitis, toxic megacolon or even a fatal outcome, are also well documented. In addition to the above mentioned clinical consequences for the individual there is also an economical impact of this disease on hospitals and health care systems. Depending upon the kind of patient population the attributable costs of CDAD may range from $3,000 to $10,000 per case.
Changing epidemiology: an increase in incidence and virulenceEarly diagnosis of CDADSurveillance of CDADEducation of staff, patients and visitorsIsolation precautions
Symptomatic patients with CDAD should be isolated in single rooms whenever possible. During an episode of diarrhoea, a large numbers of vegetative bacteria and bacterial spores are excreted. Thus, a designated toilet for the CDAD patient only should also be provided. If the number of affected patients is too high to provide single patient rooms, isolation in cohorts should be undertaken. Sometimes the implementation of a complete CDAD ward that is run by designated staff may be helpful in order to prevent further transmission.
Isolation precautions may be discontinued 48 hours after the symptoms of CDAD have resolved and bowel movements have returned to normal.
As already mentioned CD is a spore forming bacterium. Bacterial spores are highly resistant in the environment. It is important to note that alcohol does not kill bacterial spores. Therefore, alcohol-based hand rubs should not be the only hand hygiene measure employed when dealing with CDAD patients. Instead meticulous hand washing with soap and water is recommended for all staff after a potential contamination of their hands by CD spores. At present there is no recommendation for the use of antiseptic-containing soap formulae.
It is part of standard precautionary measures to wear gloves and gowns or aprons when managing patients who have diarrhoea. Of course this is also true when caring for patients suffering from CDAD. Once again, it should be remembered that the immediate vicinity of the patient is often highly
contaminated by spores.
Cleaning the immediate environmentUse of medical equipment
Patient-specific use of all medical equipment such as blood pressure cuffs is strongly recommended. In particular, electronic thermometers should not be shared between different patients, even if disposable sheaths have been employed. All such devices should always be carefully cleaned and disinfected using a sporocidal agent immediately after use with a CDAD patient. The use of disposable materials should be considered whenever possible instead of reprocessing multiple-use items.
Antimicrobial stewardshipSpecific measures in outbreaks
Infection control staff should always be informed immediately an outbreak of CDAD is suspected, and all infection control measures should then be reinforced. When doing so, the standard of cleaning the immediate environment should be particularly reviewed. A critical review of the current antimicrobial treatment policy of the patients on the ward should also be performed. CD can be cultured at the same time as microbiological diagnostic tests are performed, and the samples can be stored for subsequent molecular typing of the strains involved. This can help to elucidate the epidemiology of the outbreak.
Interim policies for patient admissions, placement and (dedicated) staffing should be administered. Sometimes the entire unit must be closed for new admissions or even vacated for an intensive environmental cleaning before re-opening.
We have to face the fact that, more than ever, CDAD represents an emerging threat in all kinds of medical departments. Because of the clinical and financial burden resulting from this disease, all efforts should be made to minimise the risk of nosocomial CD spread. Already existing infection control protocols should therefore be carefully reviewed and modified if necessary. In addition, the staff on the ward must always be aware of the possibility of CDAD in diarrhoeal patients, and strict adherence to infection control measures is highly recommended as soon as CDAD is diagnosed.
1. Pepin J, Valiquette L, Cossette B. Mortality attributable to
nosocomial Clostridium difficile-associated disease during an epidemic caused by a hypervirulent strain in Quebec. CMAJ 2005;173:1037-42.
2. Warny M, Pepin J, Fang A, Killgore G, Thompson A, Brazier J et al. Toxin production by an emerging strain of Clostridium difficile associated with outbreaks of severe disease in North America and Europe. Lancet 2005;366:1079-84.
3. Kuijper EJ, Coignard B, Tull P. Emergence of Clostridium difficile-associated disease in North America and Europe. Clin Microbiol Infect 2006;12 Suppl 6:2-18.
4. Vonberg RP, Kuijper EJ, Wilcox MH, Barbut F, Tull P, Gastmeier P et al. Infection control measures to limit the spread of Clostridium difficile. Clin Microbiol Infect 2008;14 Suppl 5:2-20.
Ralf-Peter Vonberg, MD
Institute for Medical Microbiology and Hospital Epidemiology
Medical School Hanover
Tel: +49 511 532 4431