Chapter 25 Digestive infectious diseases

Staphylococcal aureus

Enterotoxin

Transmitted:

• In nose → hands; enter food

• Grow and produce toxin in food

Coagulase positive- enzyme that coagulates blood

Refrigeration prevents toxin formation, toxin heat stable

Symptoms (toxin)

• Short incubation time

• Vomiting, cramps, diarrhea

Treatment

• rehydration

Shigellosis

Shigella

Spread person-person

S. sonnei most common, S. dysenteriae least common

Infects to intestines

Attaches to M cells-ruffles, epithelial cells

Produce toxins:

• Shiga toxin: destroys tissue

Symptoms

• diarrhea, fever, cramps

Treatment:

• antibiotics or rehydration

Salmonellosis

Salmonella

Infects M cells, inner lining of intestines

12-36 hours incubation

meat products (chicken)

• undercooked eggs, chicken etc

Symptoms

• fever, nausea, cramps, diarrhea

Treatment

• Rehydration

Typhoid Fever

Salmonella typhi

spread through human feces

Replicates inside macrophages and disseminates

2-3 week incubation

Highfever, headache, dirrhea

Treatment-

• Antibiotics

Cholera

Vibrio chloerae

Grow in small intestine, produce exotoxin

found in contanminated water

Cholera toxin

• host cells secrete water and electrolytes

Watery stools, with mucus and dead cells “rice water stools”

Symptoms:

• violent vomiting

Treatment:

• antibiotics

E. coli

Escherichia coli

normally harmless

Reservoir: cattle, contaminated food or water, leafy vegetables

Symptoms:

• diarrhea, inflammation of colon, bleeding

Treatment:

• rehydration

Helicobacter

Helicobacter pylori

Stomach cells exposed to own stomach acid

Cause ulcers by getting rid of protective musucs layer

Treatment: antibiotics

Clostridium difficile

C. diff

Exotoxins

• diarrhea to colitis

Nosocomial infection

Found in stool of healthy

Treatment: discontinuation of antibiotc and rehydration

• antibiotic

Mumps

causes infection of parotid glands 16-18 days

Transmitted in saliva and respiratory secretions

Vaccine: MMR

Symptoms: swelling of glands, fever, painful swallowing

virus

Rotavirus

typical stomach virus

common in children

transmitted through fecal-oral route

fever, diarrhea, vomiting

treatment:

• rehydration

vaccine

Norovirus

typical stomach virus

Oral transmission from food/water, aerosols from vomiting

Common cause on cruise ships

Vomiting, diarrhea, cramps

Treatment:

• rehydration

Giardia

Protozoan

Flagella

Attaches to intestinal wall

Symptoms: Malaise, nausea, weakness, weight-loss

Camping/ swimming season - contaminated water

Treatment: anti-protozoan

Hepatitis A

50% subclinical

Other 50% loss of appetite, nausea, diarrhea, fever, chills, etc

Oral transmitted

Acute infection, no chronic form

Treatment:

• vaccine; post exposure immune globulins

Hepatits B

Transmitted through blood, saliva, breast milk, semen

• get it through blood transfusions, IV drug users, sex

Acute

Subclinical

1/3 cases symptoms

• fever, nausea, abdominal pain

Treatment: none for acute

• chronic is antivirals

Vaccine

Hepatitis C

Worse

Transmitted through blood

Asymptomatic for 20 years

Majority are chronic

lead to cirrhosis or cancer

Treatment:

• drug combination