GI Infections Flashcards
Characteristics of non-inflammatory gastroenteritis
Nausea, vomiting, watery diarrhea, usually no bloody diarrhea, no WBCs in stool, toxin mediated, noninvasive, usually involves upper GI structures
Most common cause of epidemic non-inflammatory diarrhea
Noroviruses
Viral causes of non-inflammatory gastroenteritis
Noroviruses, rotovirus, adenovirus, calicivirus, astrovirus
Route of infection for viral causes of non-inflammatory gastroenteritis
Fecal-oral, noroviruses are rarely food-borne
Treatment for viral non-inflammatory gastroenteritis
Supportive
Compare noroviruses and rotoviruses
Both have 24 to 48h incubation and involve vomiting, Noro affects older children/adults, lasts 2-3 days, and is diagnosed clinically or with PCR; Roto affects children under 2, lasts 4-5 days and is diagnosed with stool antigen testing
Bacterial causes of non-inflammatory gastroenteritis
Stach aureus, Bacillus cereus, Clostridium perfringens, Vibrio cholera, and ETEC
Which bacterial non-inflammatory gastroenteritises are treated with antibiotics
V. cholera and ETEC are more serious and cause dehydration/electrolyte imbalances from overproductions of cAMP; antibiotics shorten duration
How are bacteria that cause non-inflammatory gastroenteritis spread
Food-borne
Which non-inflammatory bacteria has two clinical disease forms
Bacillus cereus has an emetic form from contaminated fried rice and a diarrheal form from contaminated meat and vegetables
What is atypical about non-inflammatory bacterial GI infections compared to other types of bacterial infections?
No fever
What is the ingested form of all the non-inflammatory bacteria
Staph aureus and Bacillus cereus: preformed enterotoxins, C. perfringens: spores, and V. cholera and ETEC: organisms themselves
Which non-inflammatory bacteria are self limiting and require no antibiotics
Staph aureus, Bacillus cereus, and C. perfringens
Diagnosis of non-inflammatory bacteria
Culture food source
Parasites causing non-inflammatory gastroenteritis
Giardia lambia is most common and seen in day cares, hikers/campers, and homosexual men, treated with tinidazole; and Cryptosporidium parvum treated with nitazoxanide
Characteristics of parasitic non-inflammatory gastroenteritis
Long incubation, watery diarrhea, cramps, worse in immunocompromised patients, diagnose with stool examination (antigen for G lambia and acid-fast for C parvum)
Spread of non-inflammatory parasites
G lambia is fecal oral and C parvum is water borne
Characteristics of inflammatory gastroenteritis
Invasive, usually involves the colon, bloody diarrhea, causes fever, fecal WBCs
Bacteria causing inflammatory gastroenteritis
Nontyphoid Salmonella, Shigella, Camylobacter, Yersinia enterocolitica, EHEC, and Clostridium difficile
Spread of inflammatory bacteria
Salmonella, Campylobacter, Y. enterocolitica and EHEC are food borne, Shigella is fecal oral, Shigella and EHEC can be person to person, and C. diff is NF
Most frequently isolated inflammatory bacteria
Campylobacter jejuni
Most communicable inflammatory bacteria
Shigella
Most common inflammatory bacteria in hospitalized patients
C. diff caused by elimination of the competition from broad spectrum antibiotics and can lead to pseudomembrane
Rare complication of nontyphiod Salmonella
Metastatic infection of atherosclerotic plaques or vascular aneurisms and osteomylitis
