chapter 25

Defenses of the stomach

Acidic

Defenses of the Small intestine:

Paneth cells; reactive enzymes and attack pathogen cell walls.

Staphylococcal Food Poisoning Pathogen

Staphylococcus aureus

Staphylococcal Food Poisoning Symptoms

Nausea, vomiting, and diarrhea in about 4 hours

Staphylococcal Food Poisoning Intoxication/Infection

Intoxication, some strains Enterotoxin (superantigen, some strains, cytokine storm TSS)

Staphylococcal Food Poisoning Diagnosis

Phage typing

Staphylococcal Food Poisoning Treatment

none

Lower Digestive System Infection Growth of a Pathogen

Incubation is from 12 hours to 2 weeks
Fever

Lower Digestive System Ingestion of toxin

Symptoms appear 1 to 48 hours after ingestion

Gastroenteritis

Diarrhea, dysentery (severe diarrhea with mucous anLower Digestive System d/or blood) Treatment: Oral rehydration therapy

Shigellosis (Bacillary Dysentery) Pathogen

Shigella spp

Shigellosis (Bacillary Dysentery) Symptoms

Tissue damage and dysentery

Shigellosis (Bacillary Dysentery) Intoxication/Infection

Infection Endotoxin and Shiga exotoxin

Shigellosis (Bacillary Dysentery) Diagnosis

Isolation of bacteria

Shigellosis (Bacillary Dysentery) Treatment

Quinolones

Invasion of Intestinal Wall by Shigella

M cells surround Peyers Patche

Typhoid Fever

Caused by Salmonella typhi Bacteria spread throughout body in phagocytes 1-3% of recovered patients become chronic carriers aka "Typhoid Mary" Poor sanitation, can be carried on the feet of flies.

Cholera

Vibrio cholerae serotypes that produce cholera toxin Toxin causes host cells to secrete chlorine anions (-neg. charge)and water, death can occur in less than one day. "Ricewater Stools

Noncholera vibrios

Usually from contaminated crustaceans or mollusks V. cholerae serotypes other than O:1, O:139, eltor V. parahaemolyticus
V. vulnificus

Escherichia coli Gastroenteritis

Pathogenic E. coli Attach to intestinal cells with fimbriae
Produce toxins May aggregate

Traveler's Diarrhea

Pathogen Enterotoxigenic, enteroinvasive, enteraggregative E. coli
Symptoms Watery diarrhea

STEC

Pathogen Shiga-toxin-producing E. coli
Symptoms Shigella-like dysentery; hemorrhagic colitis and hemolytic uremic syndrome can be fatal

Campylobacter jejuni

Symptoms Fever, abdominal pain, diarrhea
Intoxication/Infection Infection
Diagnosis Isolate bacteria
Reservoir Chickens, cow's milk

Hepatitis

An inflammation of the liver

Nucleic acid testing (NAT) is used to test

donated blood and plasma: HCV HIV West Nile virus

Virus-inactivation

is used on plasma

Giardia lamblia

intestinal protozoan parasite

Pathogen of Giardiasis

Giardia lamblia

Giardiasis symptoms

Protozoan adheres to intestinal wall, diarrhea

Reservoir of Giardiasis

water or mammals

Treatment for Giardiasis

Metronidazole; quinacrine

Cryptosporidiosis Pathogen

Cryptosporidium hominis

Cryptosporidiosis symtoms

Self-limiting diarrhea; may be life-threatening in immunosuppressed people

Cryptosporidiosis Reservoir

Cattle; water

Cryptosporidiosis Treatment

Oral rehydration

Amoebic Dysentery Pathogen

Entamoeba histolytica

Amoebic Dysentery Symtoms

Abscesses; significant mortality rate

Amoebic Dysentery reservoir

humans

Treatment for Amoebic dysentery

Metronidazole

pinworms pathogen

Enterobius vermicularis

Pinworms symptoms

Itching around anus

Pinworms Intermediate host & Definitive host

Humans

Pinworms Treatment

Pyrantel pamoate

Hookworm form of roundworm Pathogen

Necator americanus,
Ancyclostoma duodenale

Hookworm form of roundworm Symptoms

Anemia

Hookworm form of roundworm intermediate host

Larva in soil

Hookworm form of roundworm Definitive host

Human

Ascariasis a form of roundworms Pathogen

Ascaris lumbricoides

Ascariasis a form of roundworm symptoms

Few

Ascariasis a form of roundworms Intermediate host

Human

Ascariasis a form of roundworms Definitive host

Human

Trichinellosis a form of roundworm Pathogen

Trichinella spiralis

Trichinellosis a form of roundworm Symptoms

Few

Trichinellosis a form of roundworm intermediate host

Mammals

Trichinellosis a form of roundworm definitve host

human

Salmonellosis pathogen

Salmonella enterica

Salmonellosis symptoms

Nausea and diarrhea

Salmonellosis intoxication/infection

Infection Endotoxin

Salmonellosis diagnosis

Isolation of bacteria; serotyping

salmonellosis treatment

Oral rehydration

Typhoid Fever pathogen

S. typhi

Typhoid Fever symptoms

High fever, significant mortality

Typhoid Fever intoxiation/infection

Infection Endotoxin

Typhoid Fever diagnosis

Isolation of bacteria; serotyping

Typhoid fever treatment

Quinolones; cephalosporins

Cholera pathogen

Vibrio cholerae O:1 and O:139

Cholera symptoms

Diarrhea with large water loss

Non Cholera Vibrios pathogen

V. parahaemolyticus

Non Cholera Vibrios symptoms

Cholera-like diarrhea, but generally milder

Non Cholera Vibrios pathogen

V. vulnificus

Non Cholera Vibrios symptom

Rapidly spreading tissue destruction

Helicobacter Peptic Ulcer Disease pathogen

Helicobacter pylori

Helicobacter Peptic Ulcer Disease symptoms

Peptic ulcers

Helicobacter Peptic Ulcer Disease intoxication/infection

Infection

Helicobacter Peptic Ulcer Disease diagnosis

Urea breath, bacterial culture

Helicobacter Peptic Ulcer Disease treatment

Antimicrobial drugs

Clostridium and Bacillus Gastroenteritis pathogens

C. perfringens C. difficile B. cereus

Viral Diseases of the Digestive System Mumps

Pathogen mumps virus , symptoms swallen parotoid glands , incubation 16-18 days treatment vaccine

Viral Diseases of the Digestive System Viral Gastroenteritis

Pathogen rotavirus , Symptoms vomiting & diarrhea Incubation period 1-3 days Treatment oral rehydration

Viral Diseases of the Digestive System Viral Gastroenteritis

Pathogen Norovirus , Symptoms vomiting & diarrhea Incubation period 14-48 hr Treatment Oral rehydration

Hepatitis A

Transmission fecal-oral , Pathogen picornavirdae Vaccine inactivated virus

Hepatitis b

Transmission parenteral, Sti , pathogen Hepadnaviridae
liver disease yes Vaccine recombinant

Hepatitis C

Transmission parental Pathogen Filoviridae
Liver disease yes Vaccine none

Hepatitis D

Transmission Pareteral, HBV coinfection , Pathogen Deltaviridae
Liver disease yes Vaccine HBV vaccine

Hepatitis E

Transmission fecal - oral , Pathogen Caliciviridae
Liver disease no , Vaccine

Hepatitis

HAV vaccine

Mycotoxin (Fungal) Intoxications Ergot Poisoning

Pathogen Claviceps purpurea , Symptom Reduced blood to limbs ,Intoxication/ Infection ,Mycotoxin in grain
Treatment none

Mycotoxin (Fungal) Intoxications Aflatoxin Poisoning

Pathogen Aspergillus flavus , Symptoms Liver cirrhosis; liver cancer
Intoxication/ Infection Mycotoxin in food Treatment none