11. Major bacterial and viral pathogens causing enteric infections Flashcards
Gastroenteritis
Syndrome including: nausea vomiting diarrhoea abdominal discomfort
Dysentery
Inflammation of GI Tract
small stool with blood/pus
pain
fever
Enterocolitis
Inflammation of the mucosa of both large & small intestine
Enteritis
inflammation of the small intestine
Colitis
inflammation of the large intestine, especially the colon
Toxic Shock Syndrome (TSS)
Body temperature > 38.9 °C (102.02 °F)
Systolic blood pressure < 90 mmHg
Diffuse rash,erythroderma, blanching
6 types of Pathogenic Ecoli
1) EPEC
2) ETEC
3) EHEC
4) EIEC
5) EAEC
6) DAEC
EPEC
Bind to epithelial cells
disrupt microvilli
ETEC
colonize the intestinal epithelium
secrete toxins
EHEC
Shiga toxin
binds to Verotoxin* receptors on renal cells
causes :
1) haemolytic-uremic syndrome (HUS)
2) Haemorrhagic colitis (HC)
EIEC
Invade cells by endocytosis
multiply in intestinal epithelial cells
ulceration of the intestinal lining
DAEC
Sometimes cause diarrhoea
recurrent urinary tract infections
Haemolytic-Uremic Syndrome HUS
Acute renal failure
Anaemia, neurological complications
Dialysis/fluid replacement
Salmonella
Gram –ve
rod bac
O (cell wall)
H (flagella)
2000 serotypes
Causes secretion of fluid into gut
Cholera
Curved bac
gram negative rod
Diarrhoea
Dehydration
Hypovolemic shock
Treatment of cholera
prompt rehydration
salt replacement required
Viral causes of diarrhoea
1) Rotavirus
2) Norovirus
Rotavirus
Double stranded RNA Virus
double shell, non-enveloped
Loss of microvilli = less S.A to absorb nutrients