Watery Diarrhoea With Shared Facilities and Pending Stool Testing
On a medical unit, a 68-year-old man is day 6 of IV ceftriaxone for aspiration pneumonia. Overnight he has had eight unformed, watery stools; his abdomen is mildly distended and he reports cramping. Temperature 38.1 °C, HR 96, BP 126/74, WBC 18.2 × 10⁹/L. He is already on contact precautions for MRSA colonisation of the nares. Stool testing for Clostridioides difficile has been ordered but results are not expected for 24–48 hours. He shares a room with a 74-year-old man who has an indwelling urinary catheter and a healing sacral pressure injury. The two patients share one commode chair and one toilet at the end of the corridor. Two alcohol-based hand rub dispensers are mounted inside the room; the sink is out in the corridor. The unit has one cleaning cart, and terminal cleaning is performed only on discharge or transfer.
1. What infection prevention measures do you initiate now, before the stool result returns? Prioritise them and justify each.
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Manage him as infectious C. difficile until proven otherwise - the diagnostic delay is not a clinical delay.
- Move him to a single room with a dedicated toilet if one exists. If not, dedicate the commode chair to him and remove it from shared use. His roommate is highly vulnerable (indwelling catheter, open pressure injury); where a single room is unavailable, it is usually safer to move the roommate than to move the patient with diarrhoea, who is contaminating his immediate environment.
- Contact precautions: gown and gloves for every entry, removed before leaving the room, with hand hygiene immediately afterwards.
- Soap and water, not alcohol rub, after contact with him or his environment. Alcohol does not reliably kill C. difficile spores; washing physically removes them. This is the single most commonly tested point here, and it conflicts with the default behaviour on most wards.
- Dedicate equipment: thermometer, BP cuff, stethoscope and commode.
- Send the specimen promptly - only unformed stool is tested; do not send formed stool, and do not retest within 7 days if negative.
- Ask the prescriber to review the ceftriaxone and any acid suppression. Stopping or narrowing unnecessary antibiotics is part of treatment, not merely prevention.
Rationale: infectivity and environmental contamination are already occurring; every hour of waiting for the laboratory increases the exposure of staff, visitors and the roommate.
2. Explain the specific hand hygiene and environmental measures required, including what to do about the shared commode and the sink being in the corridor.
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Hand hygiene - the sink location is the practical problem. Staff must be able to wash with soap and water at the point of care. Options: a designated sink inside or immediately at the door of the room, wall-mounted soap and paper towels at the doorway, or an agreed workflow in which gloves are removed and hands washed before leaving the room, with the alcohol rub used only as an adjunct for otherwise clean hands. Teach the patient and visitors: wash after using the toilet and before eating; where a lid exists, close it before flushing; assist him rather than merely instructing him.
Environment - spores persist on surfaces. C. difficile spores resist alcohol and many routine detergents. The commode, toilet, bed rails, call bell, overbed table, door handles and the floor around the bed need cleaning with a chlorine-releasing (bleach) agent at the correct concentration and contact time - at least daily and immediately when visibly soiled. Request the sporicidal product from domestic services; 'terminal cleaning on discharge only' is not adequate for a symptomatic patient.
Roommate: monitor for diarrhoea at least twice daily and test if it develops. Keep his catheter drainage system closed and off the floor.
Linen and waste: handle as infectious; do not overfill the linen skip; double-bag only if leaking. Escalate to the infection prevention team if a second case appears on the unit.
3. What would change if the test returns positive versus negative, and how would you judge whether transmission is occurring on the unit?
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If positive: continue contact precautions until at least 48 hours after diarrhoea resolves (follow local policy, which may specify longer); continue soap-and-water hand hygiene and bleach cleaning; give oral vancomycin or fidaxomicin as prescribed (metronidazole is no longer first line for initial episodes in most current guidance); stop unnecessary antibiotics; monitor for fulminant colitis - distension, rising WCC, rising lactate, shock, ileus with no diarrhoea - and escalate urgently if these appear.
If negative: do not automatically stand down precautions if clinical suspicion remains high. A single test has limited sensitivity, and testing asymptomatic or formed stool is uninformative. Discuss with the infection team, consider alternative causes (antibiotic-associated diarrhoea, laxatives, enteral feed, other pathogens), and only then step down.
Judging transmission: look for new cases of diarrhoea on the unit, particularly in patients who share staff, equipment or toilets; review hand hygiene audit compliance for the bay; review cleaning records and whether the correct product was used; and report any cluster (two or more epidemiologically linked cases) to the infection prevention team for a formal review. A rise in unit-wide antibiotic use is also a leading indicator worth raising at ward level.