In a recent comprehensive review of 51 studies examining the global etiology of travelers’ diarrhea, C difficile was not mentioned. In most studies the occurrence of CDI was not assessed at all.[6] We are aware of only two prospective studies in which CDI was assessed in travelers with diarrhea. In a study which was performed during 1987 among US military personnel in Egypt, no cases of CDI were detected among the 183 patients with a diarrheal disease.[53] In contrast, a large prospective LY2835219 supplier study conducted in Sweden 10 years later (1996–1997) included 851 patients with diarrhea.[54] CDI was diagnosed in 101/851 (13%) of all patients with diarrhea and was

one of the two predominant recovered pathogens. Most patients had both a positive culture and a positive C difficile toxin assay. Notably, in

this cohort of 851 patients with diarrhea, 510 were returning travelers, and among them CDI accounted for 25 (4.9%) of all cases. Most cases of CDI, that were related to travel, occurred after trips to low- or medium-income countries. Most patients with CDI (61%) were younger than 60, and 41% had not received antibiotics during the month preceding the onset of diarrhea. Ribociclib supplier However, in general, the results of this study might not reflect the true incidence of CDI among travelers. The study was conducted in an infectious-diseases referral hospital, possibly overrepresenting returning travelers with more severe

diarrhea not responsive to previous empiric treatments, and overestimating the incidence of CDI in this population. In addition, interpretation of the study’s results is clouded by the inclusion of travelers to both low- and high-income countries. Empiric fluoroquinolone therapy is usually provided only to the former, making these populations essentially different with regard to the risk of CDI acquisition. In the past few years, there have been accumulating case reports of travelers anti-PD-1 antibody with CDI. A retrospective study performed in a Tropical Medicine Referral Unit in Madrid, Spain, and published in 2008 reported six travelers returning from low- and middle-income countries.[55] All patients had both a positive C difficile toxin assay and a positive culture in selective media. In this study, only travelers who had previously been treated with antibacterial agents and had persistent or recurrent diarrhea were included in this study, so cases of CDI among travelers without exposure to antibiotics, or travelers with acute diarrhea caused by C difficile may have been missed. Four of these patients were treated with ciprofloxacin with or without additional antibiotics, and two patients were treated with an unknown antibacterial agent during their trip. In 2011, another case series of nine returning American travelers diagnosed with CDI in a single center was presented in an abstract form.