Gastrointestinal Tract Infections

Content

Bacterial Food Poisoning Bacterial Enteritis and Enteric Fevers Bacterial infection of the stomach,

esophagus and intestines Gastrointestinal disease caused by other

pathogens

BACTERIAL FOOD POISONING

Food poisoning

By ingestion of food contaminated with preformed toxins

Also might contain metals, pesticides and other toxic substance

The symptoms more rapid compared to infections

Bacterial entering food

S.aureus – food handler Soil organisms such as water, feces, sewage

(nature food contamination) Others: Campylobacter jejune,

Staphylococcus aureus, Clostridium perfringens, C.botulinum and Bacillus cereus

Samples

Feces – physical determination, isolation and component analysis

Food – contaminated Gastric juice / fluid

Staphylococcus Enterotoxicosis

Basically in uncooked or inadequate cooked food. And unrefrigerated.such as??

Releasing endotoxin A or D Bacteria producing toxin instead of multiply Causing symptoms – abdominal pain,

diarrhea, nausea n vomiting

Other causes

Clostridium perfringens – undercooked meats and gravies, late onset and lasting, only during sporulation, gas gangrene and anaerobic cellulitis

Clostridium botulinum – minor in GI but major in nervous system

Bacillus cereus – contaminated rice / meat dishes, vomiting, short time onset and period of infection

Pseudomonas cocovenenans – bongkrek disease (coconut) – cause fatal

BACTERIAL ENTERITIS AND ENTERIC FEVERS

Introduction

Enteritis – an inflammation of intestine; not intoxication

Invade and damage the intestinal mucosa or deeper tissue

Small intestine – diarrhea Large intestine – dysentery (severe including

mucus, blood and pus) Leading to enteric fever such as typhoid fever

Salmonellosis

By genus Salmonella – typhi, choleraesuis and enteritidis

Detection using serotype identification – molecular/special test

Other than typhi can cause typhoid fever Normal flora of poultry, wild birds and

rodents The particular animal infected seriously / just

carrier – 90% pet reptiles carrier

Source of infection

Normal flora of poultry, wild birds and rodents

The particular animal infected seriously / just carrier – 90% pet reptiles carrier

Infected hen to the laying eggs Trace from contaminated food and water In daily life – improper preparation of food

(uncooked egg and meat/dairy product)

Pathogenesis

Abdominal pain, fever and diarrhea with blood and mucus

Onset 8 – 48 hours after ingestion Fever – endotoxin release during lysis Self-limiting lasts 1 – 4 days No need of antibiotic Infant and elderly more severe

Other species

S.typhimurium and S. paratyphi cause more serious condition – enterocolitis

Incubation period up to 10 days Cause fever and chills for 1 – 3 weeks No antibiotic suitable – increase spectrum

of normal flora of GIT Maintain the sanitary water and food

supplies

Typhoid fever

Primarily – caused by S.typhi In faulty and sewage system- uncooked shellfish,

raw fruit and raw vegetable Bacteremia and septicemia Patient having headache, malaise and fever due to

toxication Invade mucosa and excrete thru stool Infect lymphoid tissue such as Peyer’s patches (rose

spots) Antibiotic – fluoroquinolones, chloramphenicol

SA

LMO

NELLA

TYPH

I

Shigellosis

Bacillary dysentery – serovar A (dysenteriae), B (flexneri), C (boydii) and D (sonnei)

In day-care-centre, 10 organisms enough to cause infection

Contaminated food, finger, flies, feces and fomites

Asiatic cholera

Vibrio vulnificus and V. Parahemolyticus In poor country Mild and not true cholera If caused by Vibrio cholerae – rice water

stool – chronic cholera Test of microscopic observation until

serological test - IgA

Vibriosis

Largely caused by V. parahemolyticus Contaminated fish and shellfish Endotoxin released 12 hr after entering body Last fo 2 -5 days

Traveler’s diarrhea

Caused by E.coli O157:H7 Others are Campylobacter, rotavirus,

Giardia, Entamoeba, Salmonella Strain that is enterotoxigenic (ETEC) or

enteroinvasive (EIEC), enterohemorrhagic (EHEC) (also cause hemorrhagic uremic syndrome-HUS)

BACTERIAL INFECTION OF THE STOMACH, ESOPHAGUS AND INTESTINES

Peptic ulcer and Chronic Gastritis

Caused by Campylobacter pylori Is a cofactor for stomach cancer Penetration so called as perforation

PEPTIC

ULC

ER

Causes

Drinking too much alcohol Regular use of aspirin, ibuprofen, naproxen,

or other nonsteroidal anti-inflammatory drugs (NSAIDs). Taking aspirin or NSAIDs once in awhile is safe for most people.

Smoking cigarettes or chewing tobacco Being very ill, such as being on a breathing

machine Radiation treatments

Symptoms

Feeling of fullness -- unable to drink as much fluid

Hunger and an empty feeling in the stomach, often 1 - 3 hours after a meal

Mild nausea (vomiting may relieve symptom) Pain or discomfort in the upper abdomen Upper abdominal pain that wakes you up at

night

Diagnosis

Esophagogastroduodenoscopy (EGD) is a special test performed by a gastroenterologist in which a thin tube with a camera on the end is inserted through your mouth into the GI tract to see your stomach and small intestine. During an EGD, the doctor may take a biopsy from the wall of your stomach to test for H. pylori.

Upper GI is a series of x-rays taken after you drink a thick substance called barium.

VIRAL GASTROINTESTINAL DISEASES

Viral Entritis

Aslo known as rotavirus Infecting infants and children Causing watery diarrhea within 2 days 3rd virus causing fatality in children Contain dsRNA and observe using EM Diagnosis of stool using ELISA Also caused by species of Enterovirus,

Clostridium difficile and can inflammed nervous system

Contagious

 In the United States, rotavirus infection outbreaks are common during the winter and spring months. It is particularly a problem in childcare centers and children's hospitals because rotavirus infection is very contagious.

Usually this happens when kids don't wash their hands often enough, especially before eating and after using the toilet.

RO

TAV

IRU

S

Symptoms

have fever, nausea, andvomiting, often followed by abdominal cramps and frequent, watery diarrhea.

Kids may also have a cough and runny nose. Some rotavirus infections cause few or no

symptoms, especially in adults.

Hepatitis

An inflammation of liver, caused by viruses Can also caused by amoeba and toxic chemical

substance Hep A – infectious hepatitis (fecal-oral route) Hep B – serum hep (blood) Hep C – NANB hep (parenterally – blood) – liver

transplant Hep D – delta hep (blood)along wt HBV Hep E – NANBNC hep (enterically – fecal oral)

Hep A

Hep A

Hep B

Protozoan

Giardiasis Amoebic Dysentery and chronic amebiasis Balantidiasis Cryptosporidiosos Cyclosporiasis

Fungal toxin

Penicillin and Aspergilus

HELMINTHS

StrongyloidiasisTapewormsFlukeTrichinosisHookwormAscariasisTrichuriasisPinworm