COMPRE Flashcards
The ff. are naked icosahedral nucleocapsid RNA virus except:
a. Calicivirus
b. Flavivirus
c. Picornavirus
d. Reovirus
Flavivirus
Icosahedral enveloped RNA virus
Togavirus
DNA virus w/c is icosahedral capsid and is sensitive to Ether Sensitivity:
Hepadnavirus
The mode of transmission of this virus is thru direct contact through the mouth.
- Rubella Virus
- Mumps Virus
- CMV
- Hepatitis B Virus
Hepatitis B Virus
Some viruses are characterized by helical symmetry of the viral nucleocapsid. W/c of the statements about viruses w/ helical symmetry is most accurate?
a. All envelope viruses w/ helical symmetry are classified into the same virus family
b. Excess empty helical particles containing nonucleic acid are commonly produces ininfected cells
c. All human viruses w/ helical nucleocapsids posses an envelope
d. Helical nucleocapsid are found primarily in DNA-containing viruses
All human viruses w/ helical nucleocapsids posses an envelope
W/c of the ff RNA virus is resistant to Ether Sensitivity?
a. Orthomyxoviridae
b. Picornavirus
c. Reoviridae
d. Paramyxoviridae
Picornavirus
Largest DNA virus:
Poxvirus
Smallest RNA virus
Picornavirus
The ff are DNA viruses except:
- Adenovirus
- Hepadnavirus
- Poxvirus
- Picornavirus
Picornavirus
W/c of the ff virus described as double-stranded RNA virus:
a. Caliciviridae
b. Picobirnavirus
c. Togaviridae
d. Flaviviridae
Picobirnavirus
Virus-infected cells often develop morphologic changes referred to as cytopathic effects. W/c of the ff statements about virus-induced cytopathic changes is most accurate?
- They are rarely associated w/ cell death
- They may include giant cell formation
- They are pathognomonic for an infecting virus
- They can only be seen with an electron microscope
They may include giant cell formation
Described as very long and thread-like and causes severe hemorrhagic fever in Africa.
a. Filoviridae
b. Paramyxoviridae
c. Reoviridae
d. Orthomyxoviridae
Filoviridae
The following are true of viruses except:
a. some viruses are potential bioterrorism agents based on host-to-host transmission and mortality rates
b. All infections lead to new progenyvirus
c. Viruses are the smallest infectious agents and contain only 1 type of nucleic acid (DNA or RNA)
d. Known viruses are highly diverse,varying in size,shape & genetic content; some types possess a lipid envelope.
All infections lead to new progenyvirus
The viruses are usually stable between pH values of 5.0 and 9.0.
Enteroviridae
Viral infectivity is generally destroyed by heating at:
50-60 degree celsius for 30 mins
Viruses belonging to w/c of the ff groups are likely to establish latent infections?
- Poxviruses
- FIloviruses
- Herpesviruses
- Influenza viruses
Herpesviruses
The ff describes nucleocapsid:
a. are usually a collection of more than 1 non identical protein subunits
b. The protein shell, or coat,that encloses the nucleic acid genome
c. The protein-nucleic acid complex representing the package form of the viral genome
d. Morphologic units seen in the electron microscope on the surface of icosahedral virus particles
The protein-nucleic acid complex representing the package form of the viral genome
The only enveloped DNA virus:
Hepadnavirus
W/c RNA virus helical capsid, enveloped virion and is sensitive to Ether Sensitivity:
Paramyxoviridae
Picornaviridae
Reoviridae
Orthomyxoviridae
Orthomyxoviridae
The ff are used as a basis for the classification of viruses except:
a. Virion morphology, including size, shape, type of symmetry, presence or absence of peplomers, and presence or absence of membranes
b. Virus genome properties, including type of nucleic acid (DNA & RNA), size of genome, strandedness (single or double), whether linear or circular, sense (positive, negative, ambisense), segments (number, size), nucleotide sequence, percent GC content, and presence of special features (repetitive elements,isomerization)
c. Biologic properties, including natural host range, MOT, vector relationships, pathogenicity, tissue tropisms, & pathology
d. Antigenic properties, particularly reactions to various antigens
Antigenic properties, particularly reactions to various antigens
A patient developed Acute Respiratory Distress Syndrome(ARDS) after accidentally inhaling some dust at the sheep’s farm. What is the determinant of pathogenicity of this organism that can resist phagocytosis?
Polysaccharide Capsule
Which of the following scenarios would you suspect Clostridium difficile infection?
a. Ulcerative Colitis
b. Diarrhea after 2 weeks antibiotic therapy
c. pseudomembrane in the colon
d. Chronic antibiotic use
Chronic antibiotic use
Which of the ff tests for corynebacterium diphtheria uses known toxigenic C. diphtheria?
- Culture
- ELiSA
- Modified Elek immunoprecipitation method
- Polymerase ChainReaction
Modified Elek immunoprecipitation method
True of Clostridium perfringens, EXCEPT
- Found in soil
- Obligate Aerobes
- Can survive heating
- Catalase Negative
Obligate Aerobes
Which of the following will differentiate Listeria from Corynebacteria?
a. Corynebacterium is able to produce hemolysin
b. Listeria is motile at 37 degreesCelsius
c. Listeria is able to produce hemolysin
d. Corynebacterium is Non-motile
Listeria is able to produce hemolysin
A farmer developed a localized cutaneous red lesion on his hand after handling carcasses of dead pigs with red patches on the skin. What is the expected biochemical reaction of this organism?
Indole positive (bacillus anthracis?)
It is particularly difficult to differentiate Erysipelothrix rhusiopathiae from?
Lactobacillus species
Which of the following can cause food poisoning?
a. Clostridium difficile
b. Bacillus cereus
c. Clostridium perfringens
d. Clostridium botulinum
e. Bacillusanthracis
Clostridium perfringens
Has a characteristic growth of stormy or milky fermentation on liquid media
Clostridium perfringens
A man had knee surgery 2days prior when he developed compression syndrome. Which of the following signs would you suspect clostridium perfringens?
- Toxemia due to endotoxins leaking into the bloodstream
- Necrosis of the tissue at the wound closure site
- Crepitation in the subcutaneous tissues(gram pos lecture dr santos page41)
- Bullous formation at the dermalarea
Crepitation in the subcutaneous tissues(gram pos lecture dr santos page41)
A previously healthy young man initially presents with eye dropping which progresses to symmetrical paralysis of upper and lower extremities. History revealed he has eaten unrecalled donated can goods. Which of the following is true?
a. Patient should receive airway support like mechanical ventilator within 8hours(C. botulinum)
b. He should receive Tetanus Immunoglobulin
c. Give Penicillin G IV
d. He should receive Tetanus Toxoid
Patient should receive airway support like mechanical ventilator within 8hours (C. botulinum)
The movement of Listeria monocytogenes inside of host cells is caused by:
Inducing host cell actin polymerization
Which of the following has the fastest toxin effect?
a. Clostridium tetani
b. Clostridium difficile
c. Clostridium botulinum
d. Bacillus anthracis
Clostridium botulinum
Which of the following statements about Genus clostridia is true?
a. Clostridium tetani produced double zone hemolysis
b. They produce Beta hemolysis
c. Aerobic microorganisms
d. They have centrally located spores
They produce Beta hemolysis ??(gram pos lecture dr santos page22)
They have centrally located spores ??(gram pos lecture dr santos page 20) (centrally, sub terminally or terminally)
Which of the following statements differentiate Nocardia from Actinomycetes?
- Nocardia are Gram +Bacilli
- Actinomycetes produce Sulfur granules
- Actinomycetes are partially acid fast
- Cotrimoxazole is the drug of choice
Actinomycetes produce Sulfur granules
True for Listeria monocytogenes
- Catalase negative
- motile at room temperature
- Gram + spore forming rods
- Growth is non hemolytic on blood agar
motile at room temperature
A 3-year-old had watery diarrhea after taking Cheese.The organism showed tumbling motility. Which statement is true?
a. Strictly anaerobic gram +bacilli
b. potent verotoxin causes the diarrhea
c. Internalins produce the siderophores
d. Iron is an important virulence factor
Iron is an important virulence factor
A woman who had induced abortion became hypotensive and in distress after a couple of days. Which of the following statements is true about the pathogenesis of this infection?
a. Superantigen causes massive activation of the cytokines
b. Enterotoxin causes respiratory paralysis due to toxin binding at the synaptic cleft
c. Exotoxin causes myonecrosis of the smooth muscles resulting in flaccid paralysis ??
d. Endotoxin causes Septic shock by activating the polymorphonuclears
Superantigen causes massive activation of the cytokines
A man got punctured deeply by a rusty nail in a construction site. He went to the clinic after 2 days. Which of the following is the correct intervention?
- Give 3 separate doses of Tetanus Immunoglobulin ?
- Give intramuscular injection with Tetanus Toxoid 500 units
- Thorough cleaning of wound daily
- give 3 separate doses of Tetanus toxoid deep IM
- Aggressive debridement of wound
Give 3 separate doses of Tetanus Immunoglobulin ?
Growth with characteristic medusa head colonies.
a. Bacillus anthracis
b. Bacillus cereus
c. Clostridium tetani
d. Clostridium difficile
Bacillus anthracis
Which of the following does not cause principal humanillness?
a. E
b. B
c. F
d. C
e. A
C
Which of the following characteristics is correctly paired?
- Bacillus anthracis inhalational anthrax = best specimen is sputum
- Bacillus anthracis = Hemolytic on Blood Agar
- Bacillus anthracis = grow in nitrogen and carbon
- Bacillus cereus = cut glass appearance (anthracis)
Bacillus anthracis = grow in nitrogen and carbon
A 55-year-old diabetic, fish vendor accidentally pricked his right hand with the shell of an oyster. The skin became painful, swollen, and reddish with a pus-filled center. It progressed to a bullous eruption with crepitus sound associated with fever. What is the expected organism?
Gram Positive Rod with spores
All of the following statements regarding Clostridium perfringens are correct, EXCEPT:
a. It produces a double zone of hemolysis when grown on blood agar
b. It can cause intravascular hemolysis
c. It is the most common cause of antibiotic-associated diarrhea
d. It produces an enterotoxin
It is the most common cause of antibiotic-associated diarrhea
A 2 years old child was brought to the clinic due to anorexia, vomiting, and fever. Upon examination, you noticed a grayish patch at the soft palate and bull neck appearance. What is the characteristic appearance of this organism?
club-shaped rod with beaded appearance
Listeria monocytogenes is frequently a foodborne pathogens because?
- It can survive with High pH
- It can survive at 4°C
- All of them are true
- It cannot survive in High salt concentration
It can survive at 4°C
Which of the following about Genus Bacillus is correct?
- Antimicrobial resistance is due to chromosomal inheritance
- Bacillus cereus is a frequent laboratory contaminant
- Bacillus anthracis have terminally located spores x
- Bacillus subtilis and Bacillus anthracis almost have similar characteristics
Bacillus cereus is a frequent laboratory contaminant
Which of the following aerobic gram-positive bacilli is modified acid-fast positive?
- Nocardia brasiliensis
- all of them
- Erysipelothrix rhusiopathiae
- Lactobacillus acidophilus
Nocardia brasiliensis
This toxin promotes edema caused by clostridium perfringens.
Epsilon
A wool sorter personnel had a traumatic skin lesion and was noted to have a non-painful black scab after a few days. What is the antibiotic of choice?
Ciprofloxacin
A newly characterized rapidly growing Mycobacterium that has emerged as an important cause of central venous catheter associated infections is?
Mycobacterium mucogenicum
The definition of extensively drug-resistant (XDR) tuberculosis includes
- Resistance to rifampin
- All of the above
- Resistance to amikacin
- Resistance to isoniazid
- Resistance to Ofloxacin
All of the above
Which of the following are true of Mycobacteria?
a. Mycobacteria cannot be classified as either gram positive or gram negative
b. Broth media (eg, Middlebrook 07H9 and 07H12) support the proliferation of small inocula
c. media for primary culture of mycobacteria should include a non selective medium
d. are usually rod-shaped, anaerobic bacteria (aerobic)
Mycobacteria cannot be classified as either gram positive or gram negative
Broth media (eg, Middlebrook 07H9 and 07H12) support the proliferation of small inocula
media for primary culture of mycobacteria should include a non selective medium
Considered as second line drugs for M. tuberculosis.
Kanamycin
Conventional methods for identification of mycobacteria include:
a. often require 6-8 weeks for identification
b. observation of rate of growth, number of colony, and biochemical profiles
c. often require 8 weeks for identification
d. Incubation is at 35-37°C in 5-10% CO2 for up to 6weeks
observation of rate of growth, number of colony, and biochemical profiles
First-line therapy for both tuberculoid and lepromatous leprosy:
Sulfones
Which of the following Mycobacteria species is/are considered rapid growers?
a. Mycobacterium leprae
b. Mycobacterium gordonae
c. Mycobacterium avium
d. Mycobacterium chelonae
Mycobacterium chelonae
True regarding Mycobacterium leprae:
a. organisms routinely are sensitive to first-line antituberculosis drugs
b. the course is progressive and malignant, with nodular skin lesions; slow, symmetric nerve involvement
c. Specimens used for diagnosis are Scrapings from skin or oral mucosa
d. Eye involvement is uncommon
the course is progressive and malignant, with nodular skin lesions; slow, symmetric nerve involvement
In the experiments of Robert Koch,which made him known for his Koch’s postulate, he preferred the use for agar as a culture media because:
- it remained solid even at 42 degrees Celsius ?
- it is cheaper than animal eyeball
- none of the above
- it is widely available than gelatin
- it is stable at room temperature for growing smallpox
it remained solid even at 42 degrees Celsius ?
Not true of tuberculin test:
a. Larger than 10mm of induration is considered positive test result for low risk population
b. presence of induration no later than 72 hours after placement
c. larger than 10mm is considered positive for persons with increased probability of recent infection
d. 5 mm or larger of induration is considered positive
Larger than 10mm of induration is considered positive test result for low risk population
Pulmonary Mycobacterium tuberculosis infection. Which of the following features of tuberculosis is most correct?
a. In primary tuberculosis all of the infecting microorganisms are killed by the patient’s immune system
b. If tuberculosis develops years later it is a result of another exposure to Mycobacterium
c. In primary tuberculosis, an active exudative lesion develops and rapidly spreads to lymphatics and regional lymph nodes
d. The exudative lesion of primary tuberculosis often heals slowly
In primary tuberculosis, an active exudative lesion develops and rapidly spreads to lymphatics and regional lymph nodes
An 18 year old male college student sought consult at the clinic because of cough, non-productive of one month duration. Sputum was requested, the colonies were observed after four weeks. The colonies were described as rough, dry and buffed colored resembling “cauliflower”. What is the most likely causative agent?
Mycobacterium tuberculosis
Causes chronic lymphadenitis in children.
M. scrofulaceum
True of Mycobacterium intracellular is:
a. Uncommon in immunocompromised patients
b. disease has also been described in middle-aged to elderly women in the absence of chronic lung disease
•Resembles M.tuberculosis
•Most commonly isolated rapid grower from pulmonary infections
disease has also been described in middle-aged to elderly women in the absence of chronic lung disease
Initial Treatment of MAC:
Clarithromycin
A 44 year old man sought consult for multiple areas of hypopigmentation and loss of sensation on various parts of his upper extremities. Upon P.E there were hypoesthetic, hairless plaques on the upper extremities. What is the most likely organism?
Mycobacterium leprae
Which of the following causes pulmonary infections that mimic tuberculosis. It responds to therapy with INH, RIF, and EMB.
- M.gordonae
- M.chelonae
- M. kansasii
- M.ulcerans
M. kansasii
Agar used in cultivation of Mycobacteria:
Lowenstein-Jensen
Jodie, a 35 years old consulted because of multiple nodular lesions on her face,earlobes and wrist. Skin slit smear of the nodule on the earlobe showed numerous acid fast bacilli (++++). What is the most likely classification of this patient?
Lepromatous leprosy
The following does not describes Mycobacteria:
a. IGRAs can be used to screen persons for latent tuberculosis infection
b. rod-shaped, aerobic organisms
c. Both nonselective and selective media in solid and liquid forms are used to recover organisms from clinical material
d. requires acid-fast smear and tuberculin test for diagnosis
requires acid-fast smear and tuberculin test for diagnosi
An 8-year-old child has a primary pulmonary M. tuberculosis infection. Which of the ff features of tuberculosis is most correct?
- involved most often the mid-lung fields or the mid-base areas
- exudative lesion in tissue often heals slowly
- The lymph node undergoes massive caseation, which usually calcifies
- Enlarged hilar, cervical and mediastinal lymph nodes are frequently observed
The lymph node undergoes massive caseation, which usually calcifies
A 47-year-old woman presents with a 3-month history of progressive cough, hemoptysis, weight loss, and fever. Chest radiography shows bilateral cavitary disease suggestive of tuberculosis. A sputum specimen is obtained, and numerous acid-fast bacteria are seen on the smear. Patient claimed a previous PTB infection 7 yrs ago and claimed loss to follow up. Which treatment regimen is most appropriate for this patient? (kansasii)
- 2 HRZES/ 5HRE
- 2 HRZES/ 4 HRE x
- 2 HRZE/ 5HRE
- 2 HRZE/ 4HR ?
2 HRZE/ 4HR ?
All are considered scotochromogens, except?
- M.gordonae
- M. smegmatis
- M. asiaticum
- M.flavescens
M. smegmatis
MOT of M. tuberculosis:
Droplet spray
A 47-year-old woman presents with a 3-month history of progressive cough,weight loss, and fever. Chest radiography shows bilateral cavitary suggestive disease of tuberculosis. Patient was given isoniazid, pyrazinamide, rifampicin and ethambutol as initial medication. 2 weeks later px noted orange/red color urine. Px went back to your clinic. WHat would be the probable cause of the colored urine?
Rifampicin
Considered as atypical Mycobacteria:
M. avium
Not true regarding Acid Fast Stain:
a. aim of this staining is to differentiate bacteria into acid fastgroup non-acid fast groups
b. Non-acid fast cells retain the red color
c. non-acid fast organism lack the lipoidal material in their cell wall due to which they are easily decolorized, leaving the cells colorless
d. smear is decolorized with decolorizing agent (3% HCL in 95% OH)
Non-acid fast cells retain the red color
All of the following species of Mycobacterium consider soil as a reservoir except?
- M. abscessus
- M. gordonae
- M. chelonae
- M. smegmatis
M. gordonae
An 18 year old male college student sought consult at the clinic because of cough non-productive of one month duration. Also noted weight loss and chills at night. As a clinician, What is the primary diagnostic method you request for this patient?
Sputum smear ??
Sputum culture ?
A 47-year-old man presents with a 3-month history of progressive cough, hemoptysis, weight loss, and fever. Chest radiography shows bilateral cavitary disease suggestive of tuberculosis. What is the hallmark of M.tuberculosis?
Epithelioid granuloma
