Infections Of The GI Tract And Related Organs Flashcards
If vomiting occurs after an hour of food consumption, what is the likely microbial cause of food poisoning?
S. Aureus or bacillus toxins. These toxins are absorbed in stomach and act at central vomiting centre.
S aureus can be caused by contamination of salted meat products, seafood and dairy.
B cereus is a gram positive spore forming bacillus that is associated with rice.
Which organism causes food poisoning that is characterised by 12-24 hours after eating there is colicky abdominal pain and diarrhoea?
C. Perfringens. Commonly found in precooked old meats that have been reheated.
Which two bacteria can cause food poisoning like symptoms due to enteritis caused by invasion of intestinal mucosa?
Salmonella or campylobacter
Which organism causes cholera?
Vibrio cholerae
What key symptom does cholera cause?
Diarrhoea
What is the reservoir for cholera infection?
Infected individuals. Hence the disease spreads easily in conditions of poor sanitation and overcrowding.
What is the most common cause of diarrhoea in preschool infants?
Rotavirus
What key symptom is associated with rotavirus infection?
Vomiting
What is Giardia lamblia?
An anaerobic flagellate parasite of the small intestine that causes diarrhoea.
How is giardia spread?
Ingestion of infective cysts in contaminated water.
What is the treatment for giardia?
Metronidazole for at least 5 days.
What are cryptosporidium?
Sporozoan parasites transmitted via drinking water contaminated with faeces of farm animals.
What disease does campylobacter cause?
Infection is limited to intestinal epithelium and causes a secretory diarrhoea . No effective treatment.
What is enteric fever?
A systemic illness caused by salmonella typhi and paratyphi.
Where can salmonella bacteria come from?
Undercooked poultry, eggs and dairy.
Which antibiotics can cause diarrhoea via allowing overgrowth of certain bacterial species?
Clindamycin, most B lactam antibiotics.
Erythromycin can cause diarrhoea and colickly abdominal pain due to effect on gut motility.
What is pseudomembranous colitis?
An antibiotic associated diarrhoea which is accompanied by bloody stools and formation of inflammatory exudate on colonic mucosa. Caused by C.difficile.
How do we treat c.dif related pseudomembranous colitis?
Oral vancomycin or metronidazole.
What causes bacillary dysentry?
Shigella
What are the symptoms of shigellosis?
Varies from mild diarrheoa to severe diarrhoea with blood and pus in the stool.
How is diagnosis of shigella infection confirmed?
Stool culture for Non lactose fermenting gram negative bacillus.
What is hepatitis?
Inflammatory damage occurs to hepatocytes without fibrosis or regeneration.