Empiric antimicrobial therapy and infectious diarrhea. Do we need local guidelines?

In the management of acute diarrhea, administration of antibiotics may be indicated. Appropriate antimicrobial therapy can shorten illness, reduce morbidity and can be life-saving in invasive infections. Emergence of microbial strains resistant to commonly used antibiotics means that treatment failures may become common. Because of changing patterns of resistance, knowledge of recent local patterns of susceptibility can guide the initial choice of antibiotics.

A retrospective study was conducted to investigate the epidemiology of infective gastroenteritis in patients over 14years old in the region of Chania (Crete). We reviewed all positive stool cultures and susceptibilities of the pathogens recovered from patients with symptoms of acute diarrhea, from 2003 until October 2010.

Out of 194 positive stool cultures, we observed 139 cases of Salmonella enterica and 48 cases of Campylobacter jejuni. During the last 3years of observation there was an increased incidence of C. jejuni, especially after the tap water outbreak that occurred in our region in 2009.

In the vast majority of acute diarrhea in adults, antibiotics are of no benefit and overprescription may confer to side effects, costs and emergence of resistance. Antibiotics are initiated in cases of febrile diarrheas especially those believed to have moderate to severe disease. Considering the increased incidence of C. jejuni and the resistance of the great majority of isolated strains to quinolones as well as the sensitivity of Salmonella spp. to azithromycin, administration of azithromycin empirically for acute diarrhea, when indicated, could be appropriate in our region.