Microbiology Exam 3 (Part 3) -- Bacterial & Viral Diseases of the Digestive System

What condition has abdominal pain as the main symptom, and can be duodenal or gastric?

Peptic Ulcers

Which type of ulcer is relieved by food? Which type is exacerbated by food?

Duodenal ulcers = relieved by food

Gastric ulcers = exacerbated by food

What pathogen causes 90% of Peptic Ulcers

Helicobacter pylori

How is Peptic Ulcers transmitted? What worsens symtoms?

Fecal-oral transmission (likely)

-- Stress worsens ulcer symptoms

How are Peptic Ulcers diagnosed? Treated? Prevented?

Diagnosed = special GI studies to identify ulcers/presence of H. pylori

Treated = 3 drug combo (2 antibiotics & 1 drug inhibiting stomach acid)

Prevented = good hygene, adequate sewage treatment, proper food handling

What bacterial diseases are inflammation of stomach or intestines caused by bacteria, associated with contaminated food/water and poor living conditions, with enterotoxins (LI) that activate adenylate cyclase, causing diarrhea, with general symptoms such as nausea, vomiting (N/V), diarrhea, & abdominal pain/cramps?

Gastroenteritis

What type of Bacterial Gastroenteritis is an infection producing self-limiting blody and frequent diarrhea, 10 x/day for 7-10 days?

Campylobacter Diarrhea

What pathogen causes Campylobacter Diarrhea?

Campylobacter jejuni

What is the most common causative organism of bacterial gastroenteritis in the US?

Campylobacter jejuni

How is Campylobacter Diarrhea transmitted?

Consuming contaminated food, milk, water

-- poultry MC source of infection

How is Campylobacter Diarrhea diagnosed? Treated? Prevented?

Diagnosed = frequency & duration of bloody diarrhea

Treatment = most cases resolve w/o

Prevention = handwashing after handling raw poultry, cook poultry thoroughly

What bacterial gastroenteritis condition is characterized by watery diarrhea, cramps, and Nausea/vomiting, where the diarrhea is mediated by enterotoxins?

E. Coli infection (Traveler's Diarrhea)

What pathogen causes E. Coli infection (Traveler's Diarrhea)? What kind of toxin does this produce?

Escherichia coli (primarily)

- shiga-like toxin

How is E. Coli infection (Traveler's Diarrhea) transmitted?

Fecal-oral

- consumption of undercooked beef or unpasteurized milk/fruit juice contaminated w/ feces

How is E. Coli infection (Traveler's Diarrhea) diagnosed? Treated? Prevented?

Diagnosed = S/S

Treated = fluid/electrolyte replacement

Prevention = Handwashing

With E. Coli infection (Traveler's Diarrhea), what should you NOT take?

Antidiarrheal drugs -- prolongs symptoms!!

What bacterial gastroenteritis Salmonella infection results form a foodborne infection/intoxication, with non-bloody diarrhea, N/V, myalgia, fever, headache, abdominal cramps, and acute neutrophil infiltration of bowels?

Acute bacterial gastroenteritis (Salmonellosis; Salmonella food poisoning)

What bacterial gastroenteritis Salmonella infection results from bacterial invasion of the bloodstream, with fever, headache, muscle pains, malaise, loss of appetite, gastroenteritis, abdominal pain, bacteremia, "rose-colored rash" (salmon colored) and can perforate intestinal wall and cause peritonitis?

Typhoid fever (enteric fever)

What pathogen causes Acute Bacterial Gastroenteritis (Salmonellosis; Salmonella food poisoning)?

Salmonella enterica Enteritidis

Salmonella enterica Typhimurium

What pathogen causes Typhoid fever (enteric fever)?

Salmonella enterica Typhi

Salmonella enterica Paratyphi

How is Acute Bacterial Gastroenteritis (Salmonellosis; Salmonella food poisoning) transmitted?

Consuming contaminated "eggs", poultry, or inadequately pasteurized milk

How is Typhoid fever (enteric fever) transmitted?

Contaminated food/water

BONUS QUESTION: What specific bacteria did Speer come in contact w/ that sent her to the hospital

She had salmonella (not the typhoid version)... 2x in one week... from recalled peanut butter lol

(Enteritidis or Typhimurium version)

What animal can people get Salmonella from?

Turtles / other reptiles

How is Salmonella infection diagnosed? Treatment? Prevented?

Diagnosed = Salmonella in stool

Treatment =

- Salmonella food poisoning is self limiting, treat w/ fluid/electrolytes

- Typhoid fever treated w/ antibiotics

Prevention

- proper hygienes, avoiding raw eggs (esp if unpasteurized)

What is the most common fungal pathogen infecting humans? What is the most common fungal pathogen to cause disease in humans? (TQ)

Histoplasma capsulatum

Candida albicans

What bacterial gastroenteritis has abdominal cramps, fever, diarrhea, blood, pus, or mucus in stools, and tenesmus (constant urge to poop) and a fatality rate of 20%?

Shigellosis (Bacillary dysentery)

What pathogen causes Shigellosis (Bacillary dysentery)? What toxin does this produce?

4 species of Shigella

- S. Sonnei (2/3 US)

- S. flexneri (1/3 US)

- S. dysenteriae

- S. boydii

Produce diarrhea-inducing Shiga toxin (one of most potent bacterial toxins)

How is Shigellosis (Bacillary dysentery) transmitted?

Fecal-oral route

-- ingesting bacteria form contaminated hands or consuming contaminated foods (cold foods & prepped salads)

-- associated w/ poor hygiene & ineffective sewage treatment

What is the most deadly toxin? What is one of the most potent bacterial toxins?

Botulism

Shiga toxin

How is Shigellosis (Bacillary dysentery) diagnosed? Treated? Prevented?

Diagnosed = symptoms & Shigella in stool

Treatment = fluid/electrolyte replacement; antibiotics

Prevention = HANDWASHING (handling diapers)

What bacterial gastroenteritis may be asymptomatic or cause mild diarrhea, with symptoms usually beginning 2-3 days following infection with explosive watery diarrhea and vomiting, but as it progresses, the colon empties and the stool becomes increasingly watery, colorless, and odorless ("rice-water stool"), and with most severe infections, significant fluid/electrolyte losses result in dehydration, metabolic acidosis, hypokalemia, hypovolemic shock, and produces muscle cramping, irregular heartbeat, kidney failure, coma, and death (25-50% if untreated)?

Cholera

What pathogen causes Cholera? What toxin does this produce?

Vibrio cholerae

- produces cholera toxin (Exotoxins --> released from living microbes; Gram - (exception))

NOTE: has both endo & exotoxin involved here

T/F: Vibrio cholerae is the ONLY Vibrio that can survive in freshwater, so its the most common Vibrio to infect humans

TRUE

How is Cholera transmitted?

Fecal-oral route

-- ingesting contaminated food/water

(Frequent in communities w/ poor sewage and water treatment; Pandemics have occurred throughout history)

How is Cholera diagnosed? Treated? Prevented?

Diagnosed = Rice-water stools

Treated = fluid/electrolyte replacement to prevent hypovolemic shock

-- antibiotics lost in watery stool but can be given to reduce cholera toxin production

Prevention = adequate sewage/water treatment, proper hygiene

What bacterial gastroenteritis has typical gastroenteritis symptoms, and in severe cases, large sections of the colon slough off, potentially perforating the colon, leading to massive internal infection by fecal bacteria, and is life-threatening?

Antimicrobial-Associated Diarrhea

(Pseudomembranous colitis; C. diff colitis)

What pathogen causes Antimicrobial-Associated Diarrhea?

Clostridium difficile

(Produces endospores)

How is Antimicrobial-Associated Diarrhea transmitted?

Antimicrobial use can trigger disease (use facilitates overgrowth of C. difficile)

How is Antimicrobial-Associated Diarrhea Diagnosed? Treated? Prevented?

Diagnosed = bacterial toxin in stool

Treated = antibiotics or fecal transplant

Prevention = avoid unnecessary use of antimicrobials, avoid hospitalizations, probiotics

What bacterial disease has nausea/vomiting, diarrhea, and cramping, and is the MC food intoxication (bacteria itself not involved)?

Staphylococcal Food Poisoning

What pathogen causes Staphylococcal Food Poisoning?

Staphylococcus aureus

How is Staphylococcal Food Poisoning transmitted?

Contaminated (salty) food

-- room temperature (ex: sliced deli meet, puddings); outbreak associated w/ social functions

How is Staphylococcal Food Poisoning diagnosed? Treated? Prevented?

Diagnosed = S/S (*benign, self-limiting)

Treated = Fluid/electrolyte replacement

Prevented = Proper hygeine

What bacterial disease has abdominal cramps and watery diarrhea, but NO fever or nausea/vomiting?

Clostridial Food Poisoning

What pathogen causes Clostridial Food Poisoning?

Clostridium perfringens

(Endospore)

How is Clostridial Food Poisoning transmitted?

contaminated meat

- fairly benign; <24 hours

How is Clostridial Food Poisoning Treated? Prevented?

Treated = self-limiting

Prevention = Refrigeration of food reduces toxin formations, Reheating contaminated food destroys toxins

What bacterial disease causes inflammation of the intestinal tract: diarrhea, fever (weeks or months), and sometimes mimics appendicitis?

Yersinia Food Poisoning

What pathogen causes Yersinia Food Poisoning?

Yersinia enterocolitica

How is Yersinia Food Poisoning transmitted? Who's most commonly affected?

Contaminated pork (undercooked), milk, water, tofu

-- kids

How is Yersinia Food Poisoning treated? Prevented?

Treated = fluid/electrolyte replacement

Prevention = handwashing, cooking pork properly

What bacterial disease is a mild illness similar to S. aureus or C. perfringens food poisonings, most often from rice dishes that have been cooked and then held at warm temperature for several hours caused by toxins (ex: Mexican and Chinese buffets)?

Bacillus cereus Food Poisoning (Fried Rice Syndrome)

What pathogen causes Bacillus cereus Food Poisoning (Fried Rice Syndrome)?

Bacillus cereus

How is Bacillus cereus Food Poisoning (Fried Rice Syndrome) diagnosed? Treated? Prevented?

Diagnosed = isolating bacterium in incriminated food

Treated = fluid/electrolyte replacement

Prevent = proper storage, heating, cooling of foods

What viral disease has parotitis as the MC symptom along with face pain, fever, headache, and store throat, with painful enlargement of the parotid salivary glands, with men possibly getting orchitis (inflammation of testes which MAY result in sterility), and can also infect the meninges, pancreas, or (rarely) cause deafness?

Mumps

What pathogen causes Mumps?

Mumps virus (Rubulavirus)

How is Mumps transmitted? Who is most commonly affected?

Person-to-person by respiratory droplets or fomites contaminated w/ infected saliva

-- unimmunized children 2-12

How is Mumps treated? Prevented?

Treated = NONE, but infected individuals develop lifelong immunity

Prevented = MMR vaccine (almost eradicated mumps in industrialized world)

All the following cause GI infections except:

A) Vibrio

B) Histoplasma

C) Yersinia

D) Bacillus

B) Histoplasma

In most cases, peptic ulcers are associated with _______?

A. Yersinia

B. Staphylococcus

C. Helicobacter

D. Pseudomonas

C. Helicobacter

Pseudomembranous colitis can occur during antibiotic treatment and is often associated with?

A. Yersinia

B. Staphylococcus

C. Helicobacter

D. Clostridium

D. Clostridium

Turtles and frogs carry this organism that is associated with GI infections

A. Yersinia

B. Staphylococcus

C. Helicobacter

D. Salmonella

D. Salmonella

What viral disease is similar to bacterial gastroenteritis, and is caused by norovirus, astrovirus & rotavirus?

Viral Gastroenteritis

How is Gastroenteritis transmitted? What is the treatment?

Fecal-oral route

-- more cases in winter

NO treatment, just fluid/electrolyte replacement

Which pathogen causes 90% of viral enteritis, causing diarrhea, nausea, and vomiting, and is considered an emerging disease?

Norovirus

What is the #1 cause of foodborne illness in the US through fecal-oral transmission (and food especially seafood like oysters)?

Norovirus

What is the MC causative organism of gastroenteritis?

Norovirus

NOTE: remember MC pathogen for bacterial gastroenteritis is Campylobacter jejuni

Which viral gastroenteritis pathogen has star-like points, causing acute gastroenteritis with NO vomiting, is milder than norovirus with less dehydration, and passed through fecal-oral transmission?

Astrovirus

What viral gastroenteritis pathogen is the most common cause of infantile gastroenteritis, being a significant cause of death in developing countries, transmitted via fecal-oral route, and a vaccine is available to provide some protectoin?

Rotavirus

What viral disease demonstrates jaundice, abdominal pain, fatigue, vomiting, anorexia, and symptoms may occur years after initial infection with the host immune response causing much of the liver damage?

Viral Hepatitis

What 5 pathogens can cause Viral Hepatitis?

Hepatitis A virus (HAV)

Hepatitis B virus (HBV)

Hepatitis C virus (HCV)

Hepatitis delta virus (HDV)

Hepatitis E virus (HEV)

Which type of Viral Hepatitis survives on various surfaces and is resistant to common household disinfectants, with infection NOT causing chronic liver disease, and there is complete recovery occurring most of the time?

Hepatitis A

How is Hepatitis A transmitted? Is there a vaccine?

Fecal-oral route

-- infective even without developing symptoms

Vaccine available

Which type of Viral Hepatitis is usually asymptomatic or have mild symptoms, can cause severe liver damage and has been shown to be associated with liver cancer?

Hepatitis B Virus (HBV)

If Hepatitis B is coinfected with _______, it will increase the risk of permanent liver damamge?

Hepatitis D virus

How is Hepatitis B Virus (HBV) transmitted? Is there a vaccine?

Infected needles (piercing/tattoos), sexual intercourse, and passage to babies during childbirth

Vaccine is available

Which type of Viral Hepatitis is a chronic infection with few if any symptoms, with liver damage and liver failure that can occur over time?

Hepatitis C virus (HCV)

How is Hepatitis C transmitted? Is there a vaccine?

Needles, organ transplants, blood transfusions, sexual activity

NO vaccine

(treatment now available but VERY expensive in US)

What type of Hepatitis can't attach to liver cells and is known as the "satellite virus" since it requires HBV to be virulent, and plays a role in triggering liver cancer?

Hepatitis D virus (HDV)

How is Hepatitis D transmitted? Is there a vaccine?

Bodily fluids (sexual activity & contaminated needles)

NO vaccine

What type of Hepatitis is also known as enteric hepatitis, fatal in about 20% of pregnant women, and there is no treatment?

Hepatitis E (HEV)

How is Hepatitis E transmitted? Is there a vaccine?

Fecal-oral route

Only clinical trials in US; new vaccine approved in China

How is viral hepatitis Diagnosed? Treated? Prevented?

Diagnosed = Jaundice, enlargement of liver, fluid in abdomen

Treatment = Supportive care

Prevention = good hygiene and protected sex or abstinence; HAV & HBV vaccines