I believe many of these patients should be managed in their own homes; it is far better for them and far better for the hospital. However, with so little guidance for GPs to know how to safely manage these patients I recognise more needs to be done to support this management plan. So how should CDAD be managed in primary care?
Make the diagnosis
Any patient with diarrhoea over 65 years old or those 2-65 years (if they have received antibiotics within the preceding 2 weeks) should be tested for C. difficile toxin. This is done by sending a stool sample to the microbiology laboratory; on the request form give the history and the preceding antibiotic treatment, if applicable.
Note: for the purposes of CDAD, diarrhoea is defined as a stool specimen that takes the shape of the container it is put in and is equivalent to types 5-7 on the Bristol stool chart.
Next Assess for Severity
Don’t get me wrong, a patient with any risk factors for severe CDAD should be referred to a hospital for assessment by a gastroenterologist or general surgeon for intensive monitoring and treatment.
These risk factors include:
• Age > 85 years
• Temperature > 38.5oC
• Rising creatinine (if known)
• White blood cell count > 15 x 109/L
OR < 1.5 x 109/L (if known)
• Severe abdominal pain or distended abdomen
However I estimate that 90% of CDAD patients are non-severe and do not routinely need admitting to hospital. These patients should be treated as gastroenteritis and asked to report any worsening of their symptoms immediately so that they can be reviewed by their GP. Non-severe CDAD patients tend to have diarrhoea only, and no signs of colitis as listed above.
Non-severe CDAD is treated with PO Metronidazole 500mg TDS for 14 days. If the patient is unable to take Metronidazole then PO Vancomycin 125mg QDS can be used instead. Oral Vancomycin may be difficult for community pharmacies to get - this might be one of the stumbling blocks that need addressing.
If the patient still requires antibiotics for another infection than this should be discussed with a microbiologist or infectious diseases physician. Otherwise all other antibiotics should be stopped. If another antibiotic must continue it is recommended that the treatment for the CDAD be extended for at least a week after the other antibiotic has stopped.
But what about implementing infection control procedures!
Patients with CDAD should be advised to thoroughly clean their toilet and follow good hand hygiene measures, especially after going to the toilet and before eating. Up to 50% of recurrences of CDAD are reacquisitions of the bacteria from the patient’s own environment. Note: bleach kills C. difficile and its spores. As regards the isolation of CDAD patients in hospitals, this is to protect the other patients from C. difficile; not admitting these non-severe CDAD patients is the perfect infection control policy!
Follow up for response to treatment
GPs should review patients with CDAD approximately 2-3 days after starting treatment as well as at 1 week to ensure they are getting better. If the patient is no better at 1 week then refer to the hospital for further assessment including the need for: nutritional support, endoscopy, IV Metronidazole or surgery.
Remember up to 20-30% of patients with CDAD have a recurrence of symptoms after stopping treatment. So when your patient says “surely I should have been treated ‘better’ the first time” (we all know the patient either says this out loud or at least to their friends!) healthcare professionals need to understand and reiterate the following reasons in order to support treatment choice.
It is difficult to eradicate this organism from the gut for various reasons:
1. The bacteria produce spores and these are not killed by antibiotics, there are no antibiotics that are sporicidal (bleach is sporicidal to clean the environment but please don’t encourage drinking it!)
2. As the gut becomes less inflamed the intraluminal concentration of antibiotics can fall to sub therapeutic levels. This varies widely, so don’t just increase the dose which runs the risk of overdosing the patient
3. The patient may reacquire spores or bacteria from the environment (faecal/oral spread)
4. The patient is unlucky and acquires a new strain of the bacteria
The patients with recurrence of symptoms should be managed as above with an assessment of severity. If not severe, prescribe another course of PO Metronidazole 500mg (e.g. a further 14 days). If severe, then the patient should be referred to the hospital.
Other than the political attention it attracts, CDAD is not really any different to other types of infectious gastroenteritis, and the principals of its treatment are the same.
• Make the diagnosis
• Assess severity
• Start treatment
• Implement infection control procedures
• Follow up for response to treatment
If these steps are followed then there is no reason why patients with non-severe CDAD cannot be managed safely in the community. Most Microbiologists will be delighted to assist you to manage these patients in their own home.
PS Be warned - comparing your own stools to the Bristol Stool Chart is just a bit weird!