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HSS1100 midterm 2
gram positive and gram negative bacilli, mycoplasmas, mycobaterium, mycotic infections, parasites,
173
Microbiology
Undergraduate 1
03/18/2014

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Cards

Term
Which plasmid are the exotoxins for Bacillus anthracis encoded on? Name these 3 exotoxins.
Definition
-plasmid pX01
-edema factor EF
-protective antigen PA
-lethal factor LF
Term
Name an atibiotic used to treat anthrax
Definition
-penicillin
-doxycyline
-ciprofloxacin
-levofloxacin
Term
true or false?

Bacillus cereus is motile and resistant to penicillin
Definition
True
Term
Name and describe the two enterotoxins responsible for food poisoning associated with bacillus cereus
Definition
Heat labile: nausea, abdominal pain, diarrhoea, lasts 12-24 hours
Heat stabile: SEVERE nausea and vomitting, short incubation
Term
Are Clostridium bacteria aerobic or anaerobic microorganisms?
Definition
Anaerobic
Term
Name the diseases/clinical presentations of a Clostridium spp. infection
Definition
-botulism
-tetanus
-gas gangrene
-pseudomembranous colitis
Term
Why does Clostridium botulinum cause food poisoning from a lethal neurotoxin (what does the neurotoxin do?)
Definition
Neurotoxin blocks Ach release in the autonomic nervous system which causes flaccid muscle paralysis
Term
How do you treat adult botulism?
Definition
-antitoxin
-respiratory support
Term
What is a known cause of adult botulism?
Definition
-smoked fish
-improperly canning vegetables
Term
What is a known cause of infant botulism?
Definition
-honey contaminated with spores
Term
What are the clinical presentations of a 19 month old with botulism?
Definition
2-3 days of constipation,trouble swallowing, and muscle weakness
Term
How does Clostridium tetani infect a human?
Definition
-rusty nail puncture wound
-skin trauma
Term
What is the exotoxin made by Clostridium tetani and what does it cause?
Definition
-tetanosporin
causes: sustained contraction of skeletal muscles, severe muscle spasms, lock jaw, an risus sardonicus
Term
What does Clostridium perfringens cause and what are the 2 classes of infection associated with this?
Definition
-gas gangrene
1) wound infection/cellulitis
2)clostridial myonecrosis
Term
What does Clostridium difficile cause?
Definition
-antibiotic-associated pseudomembranous colitis
Term
Which exotoxins are released by Clostridium difficile and what do they cause?
Definition
Toxin A: diarrhoea
Toxin B: cytotoxic to colon cells
Term
What is the treatment of antibiotic-associated pseudomembranous colitis?
Definition
-discontinue current antibiotic regimen
-administer metronizadole or vancymycin BY MOUTH
Term
Name 2 non-spore forming rods
Definition
-Listeria monocytogenes
-Corynebacterium diptheriae
Term
Where is Listeria monocytogenes found?
Definition
-soft cheeses
-pate
-cold cuts
-unpasteurized milk
Term
True or false?
Listeria monocytogenes is a facultative intracellular aerobe?
Definition
True!
Term
Which Gram-positive bacilli crosses the 3 protective barriers (blood-brain, GI, feto-placental)
Definition
Listeria monocytogenes
Term
Which antibiotics are used to treat Listeria monocytogenes?
Definition
ampicillin or trimethoprim-sulfamethoxazole
Term
The exotoxin of which microorganism causes damage to heart and neural cells?
Definition
Corynebacterium diptheriae
Term
How to you treat diptheriae?
Definition
1)antitoxin
2)penicillin or erythromycin
3)DPT vaccine
Term
What are the 4 major groups of Enterics?
Definition
-Enterobacteriaceae
-Vibronaceae
-Pseudomonadaceae
-Bacterioidacaea
Term
Which media are used to discriminate bacteria that ferment lactose and which colour are lactose fermenters on these media? Also, do they inhibit Gram-positive or Gram-negative bacteria?
Definition
EMB Media:
-lactose fermenters are dark purple/black. Inhibits Gram-positive bacteria

MacConkey Media:
-lactose fermenters are pink-purple
-Inhibits Gram-positive bacteria
Term
What are 4 ways to biochemically classify Enterics?
Definition
-H2S production
-Hydrolysis of urea
-liquiefy gelatin
-decarboxylation of amino acids
Term
What family does Salmonellae belong to?
Definition
Enterobacteriaceae
Term
Is Salmonella able to ferment lactose? (What colour would it be on MacConkey agar?)
Definition
-unable to ferment lactose
-beige
Term
Which serovars of Salmonella enterica cause Enterocolitis?
Definition
Enteritidis
Typhimurium
Term
Which serovars or Salmonella enterica cause Enteric Fever?
Definition
Typhi
Paratyphi
Term
List some common symptoms of Enterocolitis
Definition
-nausea
-vomiting
-profuse diarrhoea
-abdominal pain
-fever
-chills
-headache
-myalgia
Term
How does someone get Enterocolitis?
Definition
Ingestion of food (pultry, meat, eggs, milk)contaminated with Salmonella enterica serovar enteritidis or typhimurium
Term
How is Enterocolitis spread?
Definition
person-to-person
Term
Why are antibiotics not recommended for Enterocolitis?
Definition
antibiotics makes it take longer for the bacteria to exit your system and does not lessen the time of the illness
Term
How long do chronic carriers of Enteric Fever excrete bacteria? Convalescent carriers?
Definition
chronic: 6 months to lifelong
convalescent: 3 months
Term
How is Enteric Fever diagnosed?
Definition
isolation of bacteria from blood (1st week) and stool and urine (2nd and 3rd week)
Term
What colour would Escherichia coli be on MacConkey agar?
Definition
pink/purple
Term
Which microorganism causes Hamburger disease?
Definition
E. coli O157:H7
Term
Which antibiotics are used to treat Listeria monocytogenes?
Definition
ampicillin or trimethoprim-sulfamethoxazole
Term
The exotoxin of which microorganism causes damage to heart and neural cells?
Definition
Corynebacterium diptheriae
Term
List some common symptoms of Enterocolitis
Definition
-nausea
-vomiting
-profuse diarrhoea
-abdominal pain
-fever
-chills
-headache
-myalgia
Term
How does someone get Enterocolitis?
Definition
Ingestion of food (pultry, meat, eggs, milk)contaminated with Salmonella enterica serovar enteritidis or typhimurium
Term
How is Enterocolitis spread?
Definition
person-to-person
Term
Why are antibiotics not recommended for Enterocolitis?
Definition
antibiotics makes it take longer for the bacteria to exit your system and does not lessen the time of the illness
Term
How long do chronic carriers of Enteric Fever excrete bacteria? Convalescent carriers?
Definition
chronic: 6 months to lifelong
convalescent: 3 months
Term
How is Enteric Fever diagnosed?
Definition
isolation of bacteria from blood (1st week) and stool and urine (2nd and 3rd week)
Term
What colour would Escherichia coli be on MacConkey agar?
Definition
pink/purple
Term
Which microorganism causes Hamburger disease?
Definition
E. coli O157:H7
Term
What does Shigellae cause?
Definition
acute diarrhoea with mucous, pus, and blood
Term
Is there a vaccine for Shigellae?
Definition
No.
Term
What percent of people does a dose of 10^5 of Shigella infect? A dose of 10^9?
Definition
10^5 = 25%
10^9 = 95%
Term
What does Vibrio cholerae cause?
Definition
cholera: acute GI illness
Term
How does the enterotoxin for Vibrio cholerae work?
Definition
-enterotoxin binds cells in small intesting
-cells secrete chlorides
-this decreases Na+ absorption
-water accumulates in gut = watery diarrhoea
-can lead to severe dehydration and death if untreated
Term
Campylobacter is part of the normal flora in who/what?
Definition
birds and domestic animals
Term
Which micro-organism is a major cause of human enteritis?
Definition
Campylobacter
Term
How do you treat a Pseudomonas infection?
Definition
Treatment is difficult because all Pseudomonas spp. are resistant to many antibiotics
Term
What are the similarities between Pseudomonas aeruginosa and Pseudomonas cepacia?
Definition
-respiratory pathogen in patients with cystic fibrosis
-opportunistic pathogen
-Gram-negative rods
Term
Name a common contaminant (micro-organism) of saline solutions and water.
Definition
Pseudomonas cepacia
Term
Which micro-organism is part of the normal nasopharyngeal flora of adults and children?
Definition
Haemophilus influenzae
Term
Can Haemophilus influenzae cause increased bronchial inflammation in patents that already have chronic bronchitis?
Definition
Yes.
Term
True or false?
There is currently no vaccine for Haemophilus influenzae in Canada.
Definition
False.
Term
Which micro-organism causes nosocomial infections and was linked to infant illness from powdered formula?
Definition
Enterobacter spp.
Term
Helicobacter pylori is the most common cause of which stomach illness?
Definition
stomach ulcers
Term
Which treatment is reccomended for a Helicobacter pylori infection?
Definition
Triple therapy treatment: antibitocs and proton pump inhibitors.
Term
What are the 4 virulence factors for Bordetella pertussis?
Definition
-Pertussis toxin
-Extra cytoplasmic adenylase cyclase
-Filamentous hemagglutinin
-Tracheal cytotoxin
Term
Where is Legionella pneumophila found?
Definition
-water
-shower heads
-water tanks
-air cooling/heating tanks
Term
Is the exposure of Legionella pneumophila by person-to-person transmission, aerosol, or both?
Definition
aerosol ONLY.
Term
What are the 4 steps of the Ziehl-Neelsen technique?
Definition
1) Ziehl-Neelsen carbol fuschsin to the slide for 5 minutes while applying heat
2) Follow with a gentle wash with water to cool the slide
3)Acid alcohol is now added to decolorize the slide
4) Wash the slide in water again and counterstain with methylene blue for 12 minutes
Term
What does Mycobacterium tuberculosis cause?
Definition
Chronic, slow-progressing pulmonary infection (tuberculosis)
Term
How long does it take to see M. tuberculosis colonies on a plate?
Definition
4-6 weeks
Term
Which medium is used to grow Mycobacterium tuberculosis?
Definition
Lowenstein-Jensen medium
Term
True or false?
Clostridium perfringens is the leading cause of death world-wide from a single infection?
Definition
False. Mycobacterium tuberculosis holds this record.
Term
Discuss the stages of Primary Tuberculosis
Definition
1)Aerosol inhalation
2)Bacteria multiply in alveoli
3)Macrophage ingestion of bacilli and formation of primary complex
4)Foci of infection in lungs (may be spread to kidneys, bones, and meninges)
~~~~~6 weeks later~~~~~~~
5) CMI is fully active, infection has stopped (majority of cases)
6) Some bacilli survive, reactivation several months to years later.

***Steps 5) and 6) are where you would get a positive tuberculin test!
Term
Describe the Mantoux test for TB.
Definition
Tuberculin solution is injected INTRADERMALLY. Wait 48-72 hours, check for induration. Record diameter of induration. >10mm positive 5-9mm doubtful, <4mm negative
Term
True or false?
M. marinum and M. fortuitum are indistinguishable from TB
Definition
True!
Term
What are the two types of leprosy caused by Mycobacterium leprae?
Definition
-Tuberculoid leprosy
-Lepromatous leprosy
Term
Discuss Tuberculoid leprosy and Lepromatous leprosy.
Definition
TL: visible nerve enlargement, few erythromatous plaques, few bacilli in infected tissues, many lymphocytes and granulomas, low infectivity

LL: no visible nerve enlargement, many erythromatous nodules, many bacilli in infected tissue, high infectivity
Term
What does Treponema pallidum cause?
Definition
Syphillis
Term
Is Treponema pallidum unculturable in vitro or in vivo?
Definition
in vivo
Term
Since Treponema pallidum is almost invisible under the Gram stain, the Geimsa stain, and the Ziehl-Neelsen stain, what can you use?
Definition
Dark field microscopy
Term
Discuss the stages of Syphilis
Definition
Primary Syphilis:
-Appearance of chancre 3-4 weeks after infection
-Fluid from lesion contains bacteria seen under dark field microscopy

Secondary Syphilis:
-6 weeks after appearance of chancre
-generalized local rash
-mucosal lesions with many treponemes

*Spontaneous remission may occur after primary OR secondary phase

Latent Syphilis:
-no symptoms of infection
-non-transmittable after 4 years
-congenital infection may occur

Late Syphilis:
-obliterative endarteritis
-can involve skin, mucosae, nervous system, cardiovascular system and tissues
Term
Since latent Syphilis is non-transmittable after 4 years, can it still cause a congenital infection?
Definition
Yes.
Term
Discuss the Non-treponemal (VDRL, RPR, Wassermann) tests for Treponema pallidum
Definition
-Non-specific: uses cardiolipin as antigen
-screening
-positive in early stages
Term
Discuss the treponemal tests for Treponema pallidum
Definition
-Specific: uses treponemal extracts
-FTA-ABS: Fluorescent Treponemal Antibody Absorption
-MHA-TP: Microhemagglutination of T. pallidum
-used to confirm positive VDRL
Term
Which micro-organism causes Lyme disease?
Definition
Borrelia burgdorferi
Term
Which parts of the body does Borrelia burgdorferi affect?
Definition
-skin
-joints
-nervous system
-heart
Term
Is Borrelia burgdorferi common in Canada and rare in the USA or rare in Canada and common in the USA?
Definition
-common in US and rare in Canada
Term
Name an antibiotic used to treat Lyme disease
Definition
-doxycyline
-amoxicilin
-cefuroxime
Term
Can Chlamydiae make their own ATP?
Definition
Nope.
Term
Can Clamydiae grow on artificial media?
Definition
Nope.
Term
What does Chlamydiae cause in males and in females?
Definition
males: urethritis
females: cervicitis
Term
John Johnson is infected with Chlamydia trachomatis and does not get treated because he is asymptomatic and does not know he is infected. What can happen to him now (complications) ?
Definition
-prostatitis
-epididymitis
Term
Jessica Jessmeister presents with chronic pelvic pain, PID, and tubal infertility after having an ectopic pregnancy last year. She is likely suffering complications from an untreated STD caused by which micro-organism?
Definition
Chlamydia trachomatis
Term
Which micro-organism is responsible for being the leading cause of blindness in the Middle East, North Africa and South East Asia?
Definition
Chlamydia trachomatis
Term
What does Chlamydia pneumoniae cause?
Definition
-sub-clinical infections
-respiratory tract infections
-mild pneumonia
Term
Which micro-organism is a bird pathogen that can be transmitted to humans and causes Pneumonia or Endocarditis?
Definition
Chlamydia psittaci
Term
Are Mycoplasma or Mycobacterium the smallest free-living bacterium?
Definition
Mycoplasma
Term
Is it true that Mycoplasma lack a true cell wall?
Definition
Yes it is.
Term
Which micro-organism is the primary cause of atypical pneumonia?
Definition
Mycoplasma pneumoniae
Term
Are Genital Mycoplasma (M. hominis, Ureaplasma urealyticum) part of normal genital flora?
Definition
Yes they are.
Term
List the levels (depth) of infection by fungal pathogens
Definition
-Superficial
-Cutaneous
-Subcutaneous
-Systemic
Term
What are Dimorphic fungi?
Definition
Fungi that grow as either yeast or mold
Term
What are Hyphae?
Definition
Threadlike, branching tubules composed of fungal cells attached end to end
Term
What are Molds (mycelia)?
Definition
Multicellular colonies composed of clumps of intertwined and branching hyphae
Term
What are Saprophytes?
Definition
Fungi that live and use organic matter such as soil, rotten vegetation as their energy source
Term
Michael Michaelson presents with tinea nigra (black coloured painless patches on soles of hands and feet) and is found to have a superficial infection caused by Exophiala werneckii. How can he treat this?
Definition
By spreading dandruff shampoo containing selenium sulfide over skin
Term
Cutaneous fungal dermatophytoses secrete the enzyme keratinase. What does this cause for the infected person?
Definition
-scaly skin
-loss of hair
-crumbling of nails

*keratinase digests keratin
Term
Which micro-organisms cause subcutaneous fungal infections that cause chromoblastomycosis?
Definition
-Phialophora
-Cladosporium
Term
Which micro-organism is an occupational hazard to gardeners because it causes subcutaneous fungal infections?
Definition
Sporothrix schenckii
Term
Name 3 fungi that cause systemic disease in humans
Definition
-Histoplasma capsulatum
-Blastomycces dermatitidis
-Coccidioides immitis
Term
Which micro-organism causes fungal infection in AIDS patients?
Definition
Cryptococcus neoformans
Term
What is the most frequently identified intestinal parasite worldwide?
Definition
Giardia lamblia (protozoan)
Term
What are the symptoms of acute giardiasis?
Definition
-diarrhoea
-weight loss
-abdominal discomfort
-nausea
-vomiting
Term
True or false?
Cysts formed by Giardia lamblia are broken apart in the colon and not excreted.
Definition
False! The cysts are shed with faeces.
Term
How would you identify Giardia lamblia in a stool sample (what technology would you use)?
Definition
bright-field microscopy or immunofluorecene microscopy
Term
What is possibly the most common sexually transmitted disease worldwide (200 million cases)?
Definition
Trichomonas vaginalis
Term
How is Entamoeba histolytica transmitted?
Definition
-faecal-oral route (person-to-person)
-contaminated water
-raw produce
-flies
Term
True or false?
Entameoba histolytica may spead to the blood to produce liver, lung, or brain abcesses?
Definition
True.
Term
Name some ways to control Entamoeba histolytica infections.
Definition
-public health education
-improved sanitation and water treatment
-wash fruits and vegetables
Term
Are Genital Mycoplasma (M. hominis, Ureaplasma urealyticum) part of normal genital flora?
Definition
Yes they are.
Term
List the levels (depth) of infection by fungal pathogens
Definition
-Superficial
-Cutaneous
-Subcutaneous
-Systemic
Term
What are Dimorphic fungi?
Definition
Fungi that grow as either yeast or mold
Term
What are Hyphae?
Definition
Threadlike, branching tubules composed of fungal cells attached end to end
Term
What are Molds (mycelia)?
Definition
Multicellular colonies composed of clumps of intertwined and branching hyphae
Term
What are Saprophytes?
Definition
Fungi that live and use organic matter such as soil, rotten vegetation as their energy source
Term
Michael Michaelson presents with tinea nigra (black coloured painless patches on soles of hands and feet) and is found to have a superficial infection caused by Exophiala werneckii. How can he treat this?
Definition
By spreading dandruff shampoo containing selenium sulfide over skin
Term
Cutaneous fungal dermatophytoses secrete the enzyme keratinase. What does this cause for the infected person?
Definition
-scaly skin
-loss of hair
-crumbling of nails

*keratinase digests keratin
Term
Which micro-organisms cause subcutaneous fungal infections that cause chromoblastomycosis?
Definition
-Phialophora
-Cladosporium
Term
Which micro-organism is an occupational hazard to gardeners because it causes subcutaneous fungal infections?
Definition
Sporothrix schenckii
Term
Name 3 fungi that cause systemic disease in humans
Definition
-Histoplasma capsulatum
-Blastomycces dermatitidis
-Coccidioides immitis
Term
Which micro-organism causes fungal infection in AIDS patients?
Definition
Cryptococcus neoformans
Term
What is the most frequently identified intestinal parasite worldwide?
Definition
Giardia lamblia (protozoan)
Term
What are the symptoms of acute giardiasis?
Definition
-diarrhoea
-weight loss
-abdominal discomfort
-nausea
-vomiting
Term
True or false?
Cysts formed by Giardia lamblia are broken apart in the colon and not excreted.
Definition
False! The cysts are shed with faeces.
Term
How would you identify Giardia lamblia in a stool sample (what technology would you use)?
Definition
bright-field microscopy or immunofluorecene microscopy
Term
What is possibly the most common sexually transmitted disease worldwide (200 million cases)?
Definition
Trichomonas vaginalis
Term
How is Entamoeba histolytica transmitted?
Definition
-faecal-oral route (person-to-person)
-contaminated water
-raw produce
-flies
Term
True or false?
Entameoba histolytica may spead to the blood to produce liver, lung, or brain abcesses?
Definition
True.
Term
Name some ways to control Entamoeba histolytica infections.
Definition
-public health education
-improved sanitation and water treatment
-wash fruits and vegetables
Term
Cats are the only definitive host of which parasite?
Definition
Toxoplasma gondii
Term
Which parasite causes encephalitis, myocarditis, and pneumonia in an immunocompromised host?
Definition
Toxoplasma gondii
Term
How is Malaria transmitted?
Definition
-Anopheline mosquitos
-blood transfusion/shared needles
-congenital infection
-"airport malaria"
Term
What are SEVERE symptoms of Malaria?
Definition
-seizures
-coma
-renal failure
-respiratory failure
Term
Is drug resistance a serious or mild problem with Malaria?
Definition
Serious!!
Term
What is the most common symptom of Cryptosporidium spp.?
Definition
water diarrhoea
Term
Which parasite causes chronic, debilitating, and potentially life threatening symptoms in the immunocompromised?
Definition
Cryptosporidium spp.
Term
True or false?
Drug treatment is available for Cryptosporidium spp.?
Definition
NO!
Term
Is Cryptosporidium an arthropod, protozoan, or helminth?
Definition
protozoan
Term
Which part of the body does Cryptosporidium infect?
Definition
typically the intestinal epithelial cells of the small intestine
Term
What is the numerically most important mode of transmission for Cryptosporidium?
Definition
WATER
Term
How is C. Parvum spread?
Definition
-person-to-person
-autoinfection
-zoonotic
Term
Cattle serve as an important reservoir host for which parasite?
Definition
C. parvum
Term
True or false?
Exposure to temperatures above 40 degrees C and below 0 degrees celcius will kill the oocysts of C. parvum?
Definition
False! above 60 and below -20
Term
The infection caused by Cyclospora cayetanensis, cyclosporiasis, is effectively treated with which antibiotic?
Definition
trimethoprim-sulfamethoxazole (bactrim)
Term
Pinworms (Enterobius vermeicularis) affect up to what percent of school-aged children in North America?
Definition
50%
Term
True or false?
Enterobius vermicularis is more of a nuisance than a health problem.
Definition
True!
Term
Scotch-tape test of the perianal area can diagnose which parasitic infection?
Definition
Pinworms
Term
Which parasite fits this description: small roundworm found worldwide in many carnivorous and omnivorous animals, including humans.
Definition
Trichinella spp.
Term
How is Trichinella spp. transmitted?
Definition
Through ingestion of larvae in raw or poorly cooked meat
Term
Matching:
__A domestic form
__B wild form
__C bears,humans, walrus
__D humans, horses, swine

1)Trichinella spiralis
2)Trichinella nativa
Definition
A)1
B)2
C)2
D)1
Term
Name a very large intestinal nematode
Definition
Ascaris lumbricoides
Term
What is the most common human helminth infection?
Definition
Ascaris lumbricoides
Term
How is Ascaris lumbricoides diagnosed?
Definition
stool examination for the presence of eggs
Term
Most cases of which parasite arise from home-prepared sushi, sashimi, and ceviche?
Definition
Anisakiasis simplex (aka whale worm or herring worm)
Term
What are the definitive hosts of Anisakiasis simplex?
Definition
-dolphins
-whales
-porpoises
Term
Since drug treatment is not effective and symptoms are often mistaken for appendicitis, diagnosis is difficult and exploratory surgery may be required thanks to which parasite?
Definition
Anisakiasis
Term
Which tapeworm is 10 meters long?
Definition
Diphyllobothrium spp.
Term
How is Diphyllobotrium spp. transmitted?
Definition
Through the consumption of raw or poorly cooked freshwater fish containing infective larvae
Term
Which tapeworms can grow up to 20 meters in length?
Definition
Taenia spp.
Term
Taenia saginata, Taenia solium.
Which is a beef tapeworm and which is a pork tapeworm?
Definition
saginata is beef
solium is pork
Term
Which tapeworm causes neurocysticercosis (intracranial hypertension, hydrocephalus, convulsive seizures)?
Definition
T. solium
Term
What are Schistosoma?
Definition
Blood flukes.
They are free-swimming larvae in fresh water that penetrate skin and develop in blood vessels surrounding intestine or bladder
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