Up to 60% of U.S. visitors to Mexico develop traveler's diarrhea (TD), mostly due to enterotoxigenicEscherichia coli (ETEC) strains that produce heat-labile (LT) and/or heat-stable (ST) enterotoxins. Distinct single-nucleotide polymorphisms (SNPs) within the interleukin-10 (IL-10) promoter have been associated with high, intermediate, or low production of IL-10. We conducted a prospective study to investigate the association of SNPs in the IL-10 promoter and the occurrence of TD in ETEC LT-exposed travelers. Sera from U.S. travelers to Mexico collected on arrival and departure were studied for ETEC LT seroconversion by using cholera toxin as the antigen. Pyrosequencing was performed to genotype IL-10 SNPs. Stools from subjects who developed diarrhea were also studied for other enteropathogens. One hundred twenty-one of 569 (21.3%) travelers seroconverted to ETEC LT, and among them 75 (62%) developed diarrhea. Symptomatic seroconversion was more commonly seen in subjects who carried a genotype producing high levels of IL-10; it was seen in 83% of subjects with the GG genotype versus 54% of subjects with the AA genotype at IL-10 gene position ؊1082 (P, 0.02), in 71% of those with the CC genotype versus 33% of those with the TT genotype at position ؊819 (P, 0.005), and in 71% of those with the CC genotype versus 38% of those with the AA genotype at position ؊592 (P, 0.02). Travelers with the GCC haplotype were more likely to have symptomatic seroconversion than those with the ATA haplotype (71% versus 38%; P, 0.002). Travelers genetically predisposed to produce high levels of IL-10 were more likely to experience symptomatic ETEC TD.Traveler's diarrhea (TD) affects up to 60% of short-term U.S. visitors to developing countries (23). Although TD is a self-limited disease with few acute complications, it can result in significant transient discomfort, cause changes in travel plans, and produce temporary incapacitation (25). TD has also been associated with long-term complications, such as postinfectious reactive arthritis, (27) Guillain-Barré neuropathy (22), and postinfectious irritable bowel syndrome (17).Up to 85% of TD cases are bacterial in origin. In Mexico, enterotoxigenic Escherichia coli (ETEC) is the single mostcommonly identified agent in the stools of travelers with diarrhea, ranging from 19% to 40% of cases (3). ETEC isolates from travelers can produce heat-labile toxin (LT), heat-stable toxin (ST), or both toxins simultaneously (LT/ST). Approximately 43% to 68% of strains isolated from subjects with TD in Mexico produce LT alone or in combination with ST (1,11,13). Contact with ETEC LT, as a result of vaccination or after natural infection, is associated with the production of LTspecific antibodies (8, 15) and may serve as an indicator of ETEC LT exposure.Previous studies carried out in Bangladesh have demonstrated that after adjusting for confounding variables, such as age and prior exposure, ETEC LT can be identified with similar frequencies in the stools of children with diarrhea and healthy controls (...

Mycobacterium brumae is a rapidly growing environmental mycobacterial species identified in 1993; so far, no infections by this organism have been reported. Here we present a catheter-related M. brumae bloodstream infection in a 54-year-old woman with breast cancer. The patient presented with high fever (39.7°C), and >1,000 colonies of M. brumae grew from a quantitative culture of blood drawn through the catheter. A paired peripheral blood culture was negative, however, suggesting circulational control of the infection. The patient was treated empirically with meropenem and vancomycin, and the fever resolved within 24 h. The catheter was removed a week later, and from the tip M. brumae was isolated a second time, suggesting catheter colonization. The organism was identified by colonial morphology, sequence analysis of the 16S rRNA gene, and biochemical tests. CASE REPORTA 54-year-old woman with a history of breast cancer presented to the emergency department for evaluation of a fever she had had for several hours. The patient's breast cancer had been diagnosed 6 months earlier, requiring a modified radical mastectomy and subsequent plastic surgery for a skin flap complication. The patient had also been treated with paclitaxol for the cancer, which led to a hypersensitivity skin rash that required a tapering dose of dexamethasone for 2 months. One month earlier (after completion of the steroid therapy), the patient began experiencing repeated episodes of fever, and workup failed to reveal specific etiology, although some lung atelectasis, likely related to the paclitaxol treatment, was noted on imaging studies. Eventually, the fever resolved with multiple antibiotics (various combinations of levofloxacin, cefepime, azithromycin, and trimethoprim-sulfamethoxazole). The present episode of fever occurred after completion of a course of azithromycin and amoxicillin-clavulanate. Notably, during the anticancer chemotherapy the patient had not been neutropenic.Physical examination revealed a fever of 39.7°C with otherwise normal vital signs. A right subclavian central venous catheter (CVC) was in place, with no erythema or drainage surrounding the insertion site. The mastectomy site was notable for a large, thick, and brown eschar without evidence of infection. The remainder of the examination was normal. Her laboratory data revealed mild anemia, a normal white blood cell count and differential, and normal platelet count. Paired quantitative blood cultures were drawn from the CVC line and a peripheral vein. The patient was admitted to the hospital and was empirically treated with meropenem and vancomycin.On the second day of admission the fever resolved. Three days later, a quantitative culture of the CVC blood (9) became positive for an acid-fast bacillus (strain MDA0695) with Ͼ1,000 colonies growing on sheep blood agar from the 10 ml of blood cultured (lysis centrifugation method with an Isolator tube; Wampole Laboratories, Princeton, N.J.). The simultaneous peripheral blood culture remained negative, however. The pos...