Assessing the selection of resistant gutflora and the restoration of normal gutflora during and after treatment of acute respiratory infection in children

Abstract

Despite the fact that a significant part of acute respiratpry infections (ARIs) are caused by viral pathogens, 85% of outpatients with ARI were prescribed antibiotics [59] due to the difficulty in the discrimination of causative agents of ARIs. Unfortunately, such overuse of antibiotics may lead to resistance in human gut flora which, in turn, is thought to be able to transfer resistant genes to pathogens. The goal of this study is to show the impact of antibiotics on human gut flora during treatment and to measure the percentage of patients receiving antibacterial therapy for a viral infection by multiplex real time PCR. Rectal samples (on admission, 1st follow up [7 days] and 2nd follow up [28 days]) from ARIs outpatients (age<16) (n=400) were plated on MacConkey agar with and without antibiotics. The results showed a significant increase in the fraction of bacteria resistant to amoxicillin, amoxicillin + clavulanic acid, ceftazidime, ciprofloxacin and gentamicin, and no significant increase to Tetracyclin, Trimethoprim+Sulfamethoxazole, and meropenem (only 3 cases were recorded). Restoration of susceptible gut flora was recorded after 28 days for Amoxicilin, Amoxicilin+Clavulanate, Ceftazimidime, and Ciprofloxacin. Nasopharyngeal swabs from a subset (n=105) of the target population were tested by multiplex real time PCR targeting 14 different viruses. An etiology was identified in 59%, with Rhinovirus (A,B or C) in 36%, Bocavirus in 15%, Adenovirus in 8%, Parainfluenzavirus 1 in 7%, Metapneumovirus in 6%, Parainflenzavirus 3 in 4%, Parainfluenzavirus 4 in 3%, Coronavirus in 2% and Parechovirus in 1% of the positives. There were no specimens found to be infected by Influenzavirus , Respiratory Syncytial Virus, or Parainfluenzavirus 2.

In summary, a significant number of ARIs outpatients were (possibly) treated inappropriately with antibiotics, which generated a short-term selection of resistance in gut flora.