Antibiotic-associated diarrhea accompanied by large-scale alterations in the composition of the fecal microbiota

J Clin Microbiol. 2004 Mar;42(3):1203-6. doi: 10.1128/JCM.42.3.1203-1206.2004.


Alterations in the diversity of the gut microbiota are believed to underlie the development of antibiotic-associated diarrhea (AAD). A molecular phylogenetic analysis was performed to document temporal changes in the diversity of fecal bacteria of a patient who developed AAD. Antibiotic administration was associated with distinct changes in the diversity of the gut microbiota, including a marked decrease in the prevalence of butyrate-producing bacteria. Following the discontinuation of the antibiotic, resolution of diarrhea was accompanied by a reversal of these changes, providing the first direct evidence linking changes in the community structure of the gastrointestinal bacteria with the development of AAD.

Publication types

  • Case Reports

MeSH terms

  • Acute Disease
  • Adult
  • Amoxicillin / adverse effects*
  • Anti-Bacterial Agents / adverse effects*
  • Bacteria / classification
  • Bacteria / drug effects
  • Bacteria / growth & development
  • Bacteria / isolation & purification
  • Clavulanic Acid / adverse effects*
  • DNA, Ribosomal / genetics
  • Diarrhea / chemically induced*
  • Drug Therapy, Combination
  • Feces / microbiology*
  • Humans
  • Male
  • Phylogeny
  • Polymerase Chain Reaction / methods
  • RNA, Ribosomal, 16S / genetics
  • Sinusitis / drug therapy*


  • Anti-Bacterial Agents
  • DNA, Ribosomal
  • RNA, Ribosomal, 16S
  • Clavulanic Acid
  • Amoxicillin