When Should C. difficile Be Suspected — and Tested?
Medically reviewed by our MD Laboratory Director (a role required by CLIA; the director's name is on file in the CMS CLIA database, #45D2048957, and can be verified independently) · Editorial policy
Diarrhea after a course of antibiotics is the classic C. diff story. But colonization is common — testing the wrong patient causes overtreatment.CLIA #45D2048957 · CAP #8722734 · Same-day results · Walk-ins welcome
When you have significant diarrhea during or after antibiotic exposure, or after a healthcare stay. C. difficile flourishes when antibiotics clear the competing gut flora. But asymptomatic colonization is common, so guidelines are firm on one point: test people with clinically significant diarrhea, not formed stool, and not people without symptoms.
Not sure what you need? Text us and we will set it up.
📱 Text (713) 832-8892 📞 Call (713) 266-0808
📱 Text (713) 832-8892 📞 Call (713) 266-0808
3707 Westcenter Dr Suite 100, Houston, TX 77042 · Walk-ins welcome
Who should be tested
| Situation | Test? |
|---|---|
| ≥3 unformed stools in 24 hours, recent antibiotics | Yes |
| Formed stool | No — a positive means colonization |
| No symptoms | No |
| Recently on laxatives | Interpret with caution |
| Severe: fever, marked leukocytosis, severe pain | Urgent clinical care — fulminant colitis is an emergency |
Go to an emergency department, not a lab, if you have: bloody diarrhea with fever, severe abdominal pain, signs of dehydration, a rigid abdomen, or you are an infant, elderly, pregnant or immunocompromised and deteriorating.
A positive C. diff result in someone with formed stool is not a diagnosis. Treating it converts a healthy carrier into a patient with an unnecessary antibiotic course.
Treatment, in outline
Guideline-based therapy exists and works — vancomycin and fidaxomicin appear in current recommendations, and the offending antibiotic is stopped where possible. Recurrence is common, and for recurrent disease, fecal microbiota-based therapies have a defined evidence base — see probiotics and FMT: where the evidence stops.
We name drugs, never doses. Treatment statements follow ACG, AGA, IDSA and CDC guidance; dose and duration are a physician's decision.
Same day, start to finish. Sample by 1:00 PM → results at 4:30 PM → if treatment is clinically appropriate, a licensed physician in our partner network sees you between 4:30 and 6:00 PM, a few minutes away. That window is reserved for patients tested here, and your slot is held the moment we take your sample — the slot is held, not hunted. On your own, a same-day appointment is nearly impossible; at an urgent care, you wait in the queue. STAT: ~2 hours, sample in by 3:00 PM.
FAQ
- Can I catch C. diff from someone?
- Spores spread in healthcare settings and survive on surfaces. Hand washing with soap and water matters — alcohol gel does not kill spores.
- Should I stop my antibiotic?
- Do not stop a prescribed antibiotic on your own. Talk to the physician — it is often part of the plan, but it is a clinical decision.
- Is a positive result always disease?
- No. Symptoms decide. That distinction is the entire point of this page.
- How fast is the result?
- Same day at 4:30 PM.
Not sure what you need? Text us and we will set it up.
📱 Text (713) 832-8892 📞 Call (713) 266-0808
📱 Text (713) 832-8892 📞 Call (713) 266-0808
3707 Westcenter Dr Suite 100, Houston, TX 77042 · Walk-ins welcome