[64] In addition, the association between the use of doxycycline and CDI in general is weak at best; in at least one large study, its use was actually associated with a significant reduction in the risk of acquiring CDI.[65] The first reported Tigecycline chemical structure case of CDI involving
the hypervirulent epidemic 027 strain in Australia was reported in 2008. The patient probably acquired CDI during a stay in the United States and suffered a recurrence after returning to Australia.[66] This case illustrates the ease with which a virulent strain of C difficile can be transported inadvertently by travelers. A small epidemiologic study from England suggested that travel outside the UK might be associated with an increased risk of community-onset CDI.[67] A recent review from the Clinical Infectious Diseases journal lists hypervirulent C difficile—alongside organisms like multiresistant Klebsiella pneumoniae as well as Acinetobacter spp, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant enterococci—as RXDX-106 a potential health-care threat transmissible through international travel. The so-called “medical tourists” pose an increased risk of transmitting C difficile through contact with under-resourced health-care systems, and because of an increased exposure to infected patients and to antibacterial agents.[68]
CDI is traditionally considered a rare cause of diarrhea in travelers, but several factors Interleukin-3 receptor led us to assume that this may be changing. The increasing incidence of community-associated CDI, the occurrence of CDI in patients
without a history of prior antibiotic use, the appearance of hypervirulent strains spread through international travel, the epidemiologic data showing that CDI may be common in low-income countries, and the frequent use of antibacterial agents including fluoroquinolones by travelers—all suggest that CDI should be considered in all travelers with diarrhea. It is unclear why the total number of reported CDI cases among travelers is low. It is theoretically possible that CDI does not commonly occur among travelers, despite the risk factors mentioned above. However, underdiagnosis may play a role in the current situation. In addition, health-care-associated CDI may be uncommon because most travelers to low-income countries do not require inpatient care. The existing case series of travelers with CDI are not sufficient to draw definite conclusions about the true epidemiology of CDI in this population. Theoretically underdiagnosis, underreporting, overrepresentation of patients from specialized referral centers, and publication bias favoring more “exotic” pathogens could have affected the current available data. A prospective study of the incidence of CDI among travelers with diarrhea is warranted. Reliable diagnostic tests should be used to evaluate travelers with acute, chronic, and recurrent diarrhea.