Investigation of multidrug-resistant Salmonella serotype typhimurium DT104 infections linked to raw-milk cheese in Washington State.

CONTEXT: Multidrug-resistant Salmonella Typhimurium DT104 has recently emerged as a cause of human and animal illness in Europe and North America. In early 1997, health officials in Yakima County, Washington, noted a 5-fold increase in salmonellosis among the county's Hispanic population. OBJECTIVES: To characterize bacterial strains and identify risk factors for infection with Salmonella Typhimurium in Yakima County. DESIGN: Laboratory, case-control, and environmental investigations. SETTING AND PARTICIPANTS: Patients with culture-confirmed Salmonella Typhimurium infection living in Yakima County and age- and neighborhood-matched control subjects. MAIN OUTCOME MEASURES: Food vehicle implication based on case-control study and outbreak control. RESULTS: Between January 1 and May 5, 1997, 54 culture-confirmed cases of Salmonella Typhimurium were reported. The median age of patients was 4 years and 91% were Hispanic. Patients reported diarrhea (100%), abdominal cramps (93%), fever (93%), bloody stools (72%), and vomiting (53%); 5 patients (9%) were hospitalized. Twenty-two patients and 61 control subjects were enrolled in the case-control study. Seventeen case patients (77%) reported eating unpasteurized Mexican-style soft cheese in the 7 days before onset of illness compared with 17 control subjects (28%) (matched odds ratio, 32.3; 95% confidence interval, 3.0-874.6). All case-patient isolates were phage definitive type 104 (DT104) (n = 10) or DT104b (n = 12), and 20 (91%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline. The cheese produced and eaten by 2 unrelated patients was made with raw milk traced to the same local farm. Milk samples from nearby dairies yielded Salmonella Typhimurium DT104. The incidence of Salmonella Typhimurium infections in Yakima County returned to pre-1992 levels following interventions based on these findings. CONCLUSIONS: Multidrug-resistant Salmonella Typhimurium DT104 emerged as a cause of salmonellosis in Yakima County, and Mexican-style soft cheese made with unpasteurized milk is an important vehicle for Salmonella Typhimurium DT104 transmission. We postulate that recent increases in human salmonellosis reflect the emergence of Salmonella Typhimurium DT104 among dairy cows in the region. Continued efforts are needed to discourage consumption of raw milk products, promote healthier alternatives, and study the ecology of multidrug-resistant Salmonella Typhimurium.

Outbreak of type A botulism and development of a botulism surveillance and antitoxin release system in Argentina.

CONTEXT: Botulism is an important public health problem in Argentina, but obtaining antitoxin rapidly has been difficult because global supplies are limited. In January 1998, a botulism outbreak occurred in Buenos Aires. OBJECTIVES: To determine the source of the outbreak, improve botulism surveillance, and establish an antitoxin supply and release system in Argentina. DESIGN, SETTING, AND PARTICIPANTS: Cohort study in January 1998 of 21 drivers of a specific bus route in urban Buenos Aires. MAIN OUTCOME MEASURE: Occurrence of botulism and implication of a particular food as the vehicle causing this outbreak. RESULTS: Nine (43%) of 21 bus drivers developed botulism, presenting with gastroenteritis, symptoms of acute cranial nerve dysfunction including ptosis, dysphagia, blurred vision, and motor weakness. One driver experienced respiratory failure. Type A toxin was detected from 3 of 9 patients' serum samples. All drivers received botulism antitoxin; there were no fatalities. Consumption of matambre (Argentine meat roll) was significantly associated with illness. Among 11 persons who ate matambre, 9 developed illness, compared with none of those who did not eat it (P<.001). The matambre had been cooked in water at 78 degrees C to 80 degrees C for 4 hours, sealed in heat-shrinked plastic wrap, and stored in refrigerators that did not cool adequately. Subsequently, a botulism surveillance and antitoxin release system was established. CONCLUSIONS: Insufficient cooking time and temperatures, storage in heat-shrinked plastic wrap, and inadequate refrigeration likely contributed to Clostridium botulinum spore survival, germination, and toxin production. A rapid-response botulism surveillance and antitoxin release system in Argentina should provide more timely distribution of antitoxin to patients and may serve as a model for other nations.

Gastrointestinal complications of chronic granulomatous disease: case report and literature review.

Chronic granulomatous disease (CGD), an inherited disorder of phagocytic leukocyte function, is characterized by recurrent infections with catalase-positive organisms. Gastrointestinal (GI) tract involvement, present in the majority of affected individuals, may be present initially and recurrently, mimics other entities such as inflammatory bowel disease, and causes substantive morbidity and mortality. Disorders of motility, ulceration, obstruction, and infection (e.g., abscesses) occur from the mouth to the anus and stereotypically manifest with vomiting, diarrhea, abdominal pain, weight loss, and fever. Careful physical examination, in concert with appropriate diagnostic studies, is necessary to delineate intraabdominal pathologic processes. Abdominal radiographs, ultrasonography, computerized tomography, and endoscopy are useful ancillary diagnostic procedures. Drainage of accessible abscesses, antimicrobial therapy based on organisms cultured from blood and tissue, and interferon gamma may lead to suppression or eradication of infections and resolution of symptoms. Corticosteroids are useful for gastric outlet obstruction and sulfasalazine and cyclosporine for large bowel disease. Gallbladder dysfunction may be ameliorated, as in our patient, with administration of cholestyramine.

Stress-induced changes in intestinal transit in the rat: a model for irritable bowel syndrome.

Stress in humans commonly results in gastrointestinal dysfunction, which is characterized by its symptomatology because the etiology is completely unknown. We developed an animal model in which to study the effects of stress on the gastrointestinal tract, and characterized the model as a stressor by evaluating endocrine and analgesic responses to mild restraint. Mild restraint (wrap restraint) elevated plasma levels of adrenocorticotropic hormone and beta-endorphin, and caused analgesia. The different regions of the gastrointestinal tract responded differently to the stress stimulus. Gastric emptying was not affected, small intestinal transit was inhibited, and large intestinal transit was stimulated by stress, and there was an associated increase in fecal excretion. Wrap-restraint stress did not result in the formation of ulcers. There was a strong correlation between stress-induced adrenocorticotropic hormone release and stress-induced intestinal dysfunction over a 24-h period that suggested a circadian influence. However, neither exogenous adrenocorticotropic hormone nor beta-endorphin had any effect on intestinal transit. Furthermore, neither adrenalectomy nor hypophysectomy prevented the response of the intestine to stress, suggesting that neither adrenal nor pituitary-derived factors are responsible for mediating the effects of stress on the gut. We conclude that wrap-restraint stress produces different effects on different regions of the intestine, suggesting that the small and large intestines are independently regulated and can respond differently to different stimuli. There were similarities between the intestinal effects of wrap-restraint stress in rats and intestinal symptoms associated with stress and irritable bowel syndrome in humans. Therefore, wrap restraint may be an appropriate animal model in which to study stress-related intestinal dysfunction. The mechanisms by which stress affects intestinal transit are still unresolved; however, the intestinal effects of stress are not mediated by either pituitary or adrenally derived factors.

Corticotropin-releasing factor directly mediates colonic responses to stress.

A new stress model in rats produced changes in intestinal function that resemble patterns of intestinal dysfunction associated with stress in humans: small intestinal transit was inhibited, large intestinal transit was stimulated, and fecal excretion was stimulated. To evaluate the role of corticotropin-releasing factor (CRF) in mediating the effects of stress on the intestine, we studied the actions of exogenous CRF on small and large intestinal transit in the rat and characterized the effects of pharmacological blockade of CRF receptors on stress-induced intestinal dysfunction. Administration of exogenous CRF (0.3-10.0 micrograms iv or icv) resulted in dose-related inhibition of gastric emptying, inhibition of small intestinal transit, stimulation of colonic transit, and stimulation of fecal excretion. The actions of exogenous CRF mimicked the effects of stress on the motor activity of the gastrointestinal tract. Administration of alpha-helical CRF-(9-41) (50 micrograms iv or icv), an antagonist of CRF, prevented the stress-induced increase in large intestinal transit and the associated increase in fecal excretion. These data suggest that endogenous CRF may mediate stress-induced changes in colonic function.

A cyclic somatostatin analog that precipitates withdrawal in morphine-dependent mice.

We evaluated the ability of the mu selective, peptidic, opioid antagonist CTP to precipitate withdrawal in morphine-dependent mice after intracerebroventricular (i.c.v.) and subcutaneous (s.c.) administration. The withdrawal syndrome evoked by i.c.v. CTP was different in some respects from that observed after i.c.v. naloxone. Naloxone, given i.c.v., produced shakes and tremors, defecation, diarrhea, wet dog shakes, jumping and weight loss. In contrast, the prominent signs following i.c.v. CTP were grooming, tremors and shakes, defecation, wet dog shakes and weight loss. CTP treated mice exhibited a greatly reduced incidence of jumping behaviors and diarrhea. While s.c. naloxone evoked similar effects to i.c.v. naloxone, CTP given s.c. stimulated defecation and modest weight loss only. The differences in the profile of withdrawal signs between naloxone and CTP may be related to their differences in receptor selectivity or possibly to their respective alkaloidal and peptidic natures. The relative lack of behavioral effects seen after s.c. CTP probably reflects the inability of CTP to pass through the blood brain barrier, and indicates that although the majority of withdrawal signs are mediated by centrally located opioid receptors, the gastrointestinal tract can be withdrawn independently of the central nervous system.