#idboardreview 30 M Crohn’s on methotrexate, adalimumab & recent prednisone/natalizumab presents w/2d F, abd pain, non-bloody diarrhea. Ate cantaloupe from farmer’s market. No travel/animals. Normal labs. +BC. Diagnosis? #medEd #idmedEd
+BC: When considering bacterial infections that cause GI dz: think about foodborne illnesses mediated by toxins such as preformed Bacillus cereus toxin, staphylococcal toxins, or even toxins transmitted by fish or shellfish
Nontyphoidal salmonellae & campylobacter are most common bacterial enteritis in 🇺🇸 associated w/ poultry &salmonellae w/ eggs. Salmonella serotypes vary by location but S enterica serotype Enteritidis & S enterica serotype Typhimurium are common& possible,m
Campylobacter jejuni & C. coli are most common of campylobacter species, which are less likely than salmonellae to cause bacteremia. There are other less common campylobacter species as C. fetus, which has a vascular tropism may cause vascular infection in immunocompromised host
Shiga-toxin–producing Escherichia coli characteristically causes bloody diarrhea and no fever and sometimes toxin-mediated renal failure
Unpasteurized milk, soft cheeses, and delicatessen foods can be a source of foodborne illness, particularly with Listeria monocytogenes. Infliximab, which this patient had received earlier, is a known risk factor for listeriosis. The patient reportedly ate fresh fruit
#listeria risk factors
Healthy, nonpregnant adults who are infected with L. monocytogenes may have no symptoms or only mild, self-limited diarrhea, whereas pregnant women typically have influenza-like symptoms with fever sometimes, but not always, preceded by GI sx since organism enters via GI tract
syndrome of acute febrile gastroenteritis, characterized by fever, diarrhea, and relatively infrequently vomiting, typically occurs after the ingestion of food containing a large number of organisms
Diarrhea associated w/ outbreaks is not bloody. Bacteremia, sepsis & meningitis are more likely in very young, elderly, pregnant women, & immunosuppressed, such as this patient. GI dz specifically IBD risk factor for severe/prolonged listerial infection of GI tract
Abnormalities of bowel may cause altered motility & longer life of organism in GI tract, which could result in ⬆️risk of systemic invasion. patient had several risk factors for severe dz: inflammatory bowel disease, glucocorticoid use, and immunomodulating monoclonal antibodies
Gram's staining revealed non–spore-forming, small, gram-positive rods singly and in pairs and short chains from aerobic and anaerobic blood-culture bottles, strongly suggestive of listeria species
Colony growth after 18 to 24 hours of incubation allowed confirmatory testing including a positive catalase test, observation of motility in semisolid agar, growth in 6.5% sodium chloride broth, and a narrow zone of β-hemolysis on a blood agar plate
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