Case series / case reportcited by the Tayebat archiveabstract only checked★ key study A-ABX-09 in-depth review
Gut bacteria after ciprofloxacin
Incomplete recovery and individualized responses of the human distal gut microbiota to repeated antibiotic perturbation.
Overview
Dethlefsen L & Relman DA. Proc Natl Acad Sci U S A 2011 · PMID 20847294 · DOI 10.1073/pnas.1000087107
In 3 people, gut bacteria changed quickly and did not fully return to the original state.
Does the study support the specific claim? Yes · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Track microbiota.
- How was the study done?
Sequencing.
- How many people, animals or samples were studied?
3 adults.
- What was actually found?
Incomplete recovery.
- What do the results mean in everyday life?
Consequences unknown.
- What are the study's limitations?
n=3.
- What does it say about Elawady's specific claim?
Supports.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Health effects.
Scientific in-depth review
1. Full reference
- Authors
- Dethlefsen L, Relman DA
- Journal
- Proc Natl Acad Sci U S A
- Year
- 2011
- Identifier
- PMID 20847294 DOI 10.1073/pnas.1000087107 · PMC3063582
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
The authors declare no conflict of interest.
2. Research question
Response of gut microbiota to repeated antibiotic perturbation
3. Study design and population
- Study design
- Case series / case report – Longitudinal 16S sequencing of distal gut microbiota over 10 months spanning two ciprofloxacin courses
- Population
3 healthy adults
- Country
USA
- Period
10 months
- Sample size
3 (52-56 samples each)
4. Methods and endpoints
- Exposure / intervention
Ciprofloxacin 2 courses
- Comparator
Baseline
- Endpoints
Community composition/diversity
- Statistical methods
Descriptive
5. Actual results
- Results
Loss of diversity within 3-4 days; return began by 1 week after course but often incomplete; final composition altered from initial state in all subjects.
- Absolute risks
not reported
- Authors' conclusion
Antibiotic perturbation may cause shift to an alternative stable state, 'the full consequences of which remain unknown'.
6. Strengths
- Dense sampling
7. Weaknesses
- n=3
- No clinical outcomes
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- not assessable
- Rationale
Descriptive.
9. Assessment of the statistical interpretation
10. Relevance to the specific claim
11. Independent contrary findings
12. Transferability to Germany and Europe
High.
13. Overall methodological judgement
Informative but tiny.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | not assessable |
| Precision of results | low |
| Directness | indirect |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | essentially correct but incomplete |
14. Open questions
Clinical relevance.
15. Linked fact checks
- Antibiotic courses profoundly disrupt the gut microbiome; recovery can be incomplete, with changes lasting months to years. – Studies supporting the claim
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
A single course of ciprofloxacin caused rapid, profound loss of gut microbial diversity that did not fully recover months later.
- A. What was actually studied?
Microbiota response.
- B. What did the authors find?
Profound, incomplete recovery.
- C. What conclusions do the authors themselves draw?
Consequences unknown.
- D. What does the archive derive from it?
'Recovery was incomplete in every subject' (archive finding text).
- E. Is this derivation scientifically justified?
Essentially correct (abstract: return 'often incomplete'; composition altered in all subjects at end); archive omits 'consequences unknown'; two courses, not one.
- Adequacy of the interpretation (by the archive)
- essentially correct but incomplete