Focus on antibiotic associated diarrhea (AAD)
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Antibiotics are a powerful tool in the fight against bacterial infections, however they also disrupt the protective intestinal microbiota and this can lead to unintended consequences including antibiotic-associated diarrhea (AAD) in as much as 35% of patients.17,18,19The incidence of AAD depends on several factors: 17,18,19 age (among children this percentage can reach up to 80%) 15, setting, type of antibiotic, etc. Most of the time, AAD is caused by antibiotic-induced dysbiosis, is of mild intensity and is self-limiting, lasting between 1 and 5 days.
While the etiologies for AAD are diverse, approximately one-third of AAD cases are attributed to C. difficile. Under certain conditions, C. difficile will trigger an inflammatory response leading to a range of clinical outlooks, from mild diarrhea to pseudomembranous colitis, toxic megacolon and/or death.17
ESPGHAN 2023 RECOMMENDATIONS
In 2023, the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) Special Interest Group on Gut Microbiota and Modifications set out updated recommendations for the use of probiotics in the management of selected paediatric gastrointestinal disorders:20
“If the use of probiotics for preventing antibioticassociated diarrhea (AAD) is considered because of the existence of risk factors such as class of antibiotic(s), duration of antibiotic treatment, age, need for hospitalization, comorbidities, or previous episodes of AAD, healthcare professionals may recommend high doses (≥5 billion CFU/day) of S. boulardii or L. rhamnosus GG started simultaneously with antibiotic treatment to prevent AAD in outpatients and hospitalized children (certainty of evidence: moderate; grade of recommendation: strong).”
CLINICAL CASE by Pr. Aldo Maruy
- A 10-year-old patient came to the clinic with a seven-day history of diarrhea. From the onset, the child had been producing each day two or three liquid stools with mucus, though without blood. The mother said there had been neither fever nor vomiting. On clinical examination, the child seemed well and appeared to be adequately hydrated.
- The doctor requested a stool culture and OVA & parasite checks; these were negative.
- An antecedent had not initially been considered: six weeks before, the child had had a respiratory infection which was treated with antibiotics.
- Late-onset Antibiotic Associated Diarrhea (AAD) was then suspected. The patient received probiotics and improved within a week.
- AAD can take anywhere from 2 hours to 8-10 weeks to develop after antibiotic use.
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EXPERT OPINION
Antibiotic Associated Diarrhea (AAD) is a common side effect of antibiotics. Age, spectrum of antibiotics used, underlying illness and recent surgery have been identified as risk factors. Recent evidence shows a new one: composition of the microbiota. In patients treated with β-lactams, higher relative abundances of Bacteroides were inversely associated with AAD while higher baseline abundance of Bifidobacterium species and Lachnospiraceae and amino acid biosynthesis pathways (AABP) were associated with AAD. Relative abundances of potentially protective taxa and levels AABP may distinguish children who did and did not experience AAD. Further studies are needed to investigate whether similar trends are observed across different antibiotic types. The identified potentially protective taxa may inform the development of preventive approaches for AAD.