MICROBIO LEC 4 Flashcards
Which of the following does NOT pertain to infant botulism?
A. Symptoms include flaccid paralysis and respiratory complications
B. Symptoms include “floppy baby” appearance
C. Neurotoxin is not involved in the disease process
D. Ingested spores can germinate in the immature intestine of the neonate
C. Neurotoxin is not involved in the disease process
Which of the following is NOT characteristic of Bacillus anthracis?
A. Capsule and exotoxins are virulence factors
B. Reservoir includes infected grazing animals and contaminated soil
C. Anaerobic
D. Spore-former
C. Anaerobic
Disease/s caused by Streptococcus pneumoniae include
A. otitis media
B. meningitis
C. pneumonia
D. All of these choices are correct
D. All of these choices are correct
Which organism can infect deeper wound sites and produce exotoxins, enzymes, and gas that cause tissue and muscle necrosis?
A. Clostridium perfringens
B. Clostridium tetani
C. Clostridium botulinum
D. Clostridium difficile
A. Clostridium perfringens
A specimen was collected from a deep wound. A smear was prepared and Gram stained and samples were inoculated onto two blood agar plates. Both blood agar plates were incubated for 48 hours at 35⁰C, but one blood agar plate was incubated aerobically and the other was incubated in an anaerobe jar. The Gram stain of the original specimen showed large gram-positive bacilli. After incubation, there was no growth on the blood agar plate that was incubated aerobically, but the plate incubated in the anaerobe jar grew beta hemolytic colonies. A Gram stain of these colonies showed large gram positive bacilli, some with unstained inclusions, suggestive of endospores. What is the most likely genus of bacteria observed?
A. Mycobacterium
B. Bacillus
C. Clostridium
D. Corynebacterium
C. Clostridium
Which of the following is not true about diphtheria?
A. A pseudomembrane may form in the back of the throat
B. It is an upper respiratory infection
C. Humans can be healthy carriers
D. It is a zoonosis
D. It is a zoonosis
The food-borne disease that involves neurotoxin is
A. botulism
B. Bacillus cereus intoxication
C. gastrointestinal anthrax
D. Clostridium perfringens gastroenteritis
A. botulism
Production of a neurotoxin that binds to target sites on spinal cord neurons responsible for inhibiting skeletal muscle contraction is a characteristic of
A. Clostridium perfringens
B. Clostridium difficile
C. Clostridium botulinum
D. Clostridium tetani
D. Clostridium tetani
Which of the following pertains to diphtheria?
A. It results in meningitis
B. Symptoms include vomiting and diarrhea
C. It is prevented by the DTaP immunization DTaP stands for Diphtheria, Tetanus, and Pertussis given at 2 months of age
D. All of the choices are correct
C. It is prevented by the DTaP immunization DTaP stands for Diphtheria, Tetanus, and Pertussis given at 2 months of age
Which is not correct about Bacillus cereus?
A. Associated with cooked rice, potato, and meat dishes that are stored at room temperature
B. Causes a zoonosis
C. Produces enterotoxins
D. Causes food-borne intoxication
B. Causes a zoonosis
Production of a neurotoxin that prevents acetylcholine release from motor neurons at neuromuscular junctions is a characteristic of
A. Clostridium tetani
B. Clostridium botulinum
C. Clostridium perfringens
D. Clostridium difficile
B. Clostridium botulinum
Which of the following does NOT pertain to Clostridium difficile infection?
A. It is a colitis that is a superinfection
B. It is due to ingestion of contaminated, improperly stored, cooked meats and gravies
C. It is a major cause of diarrhea in hospitals
D. It may be on the rise due to increased use of gastric acid inhibitors
B. It is due to ingestion of contaminated, improperly stored, cooked meats and gravies
What is the usual cause of pseudomembranous colitis?
A. Therapy with broad-spectrum antibiotics leading to superinfection by C. difficile
B. Improperly home-preserved foods containing botulin toxin
C. Consuming unpasteurized dairy products containing Listeria monocytogenes
D. Living in close contact with someone infected with C. perfringens
A. Therapy with broad-spectrum antibiotics leading to superinfection by C. difficile
What do the bacteria that cause botulism, tetanus, and diphtheria have in common?
A. Each of these diseases is caused by an endospore forming bacterial species
B. Each of these bacteria make an exotoxin that is responsible for the disease
C. Vaccines are widely used to prevent each of these diseases
D. Each of these diseases is caused by oligately anaerobic bacteria
B. Each of these bacteria make an exotoxin that is responsible for the disease
Which form of anthrax involves a black eschar on the skin?
A. Pulmonary
B. Gastrointestinal
C. Cutaneous
D. All of the choices are correct
C. Cutaneous
Anthrax is
A. a zoonosis
B. transmitted by contact, inhalation, and ingestion
C. a disease that, in humans, can cause a rapidly fatal toxemia and septicemia
D. All of the choices are correct
D. All of the choices are correct
Case: 29-year old Filipino male zoologist, came home from New Zealand after research with sheep 3 weeks ago:
Complaint: cough, dyspnea, and substernal pain
Diagnostics: x-ray shows mediastinal widening
Culture and Gram Stain: large gram-positive rods
What toxin is known as a major virulence factor of etiologic agent and cause of death in infected patients?
A. Protective antigen
B. Edema toxin
C. Lethal toxin
D. Exotoxin
C. Lethal toxin
Case: 29-year old Filipino male zoologist, came home from New Zealand after research with sheep 3 weeks ago:
Complaint: cough, dyspnea, and substernal pain
Diagnostics: x-ray shows mediastinal widening
Culture and Gram Stain: large gram-positive rods
What is the drug of choice to target the etiologic agent?
A. Ciprofloxacin
B. Cotrimoxazole
C. Clindamycin
D. Cefuroxime
A. Ciprofloxacin
Which of the following treatment modalities is of utmost priority for a patient with a necrotic wound most likely infected with C. perfringens?
A. Immediate administration of Polyvalent antitoxin
B. Extensive surgical debridement in the operating room
A. Hyperbaric oxygen
D. Immediate administration of antibiotic therapy
B. Extensive surgical debridement in the operating room
Which of the following is NOT used in the treatment of B. cereus infection?
A. Cefuroxime
B. Aminoglycosides
C. Clindamycin
D. Ciprofloxacin
A. Cefuroxime
Which of the following is a characteristic of Bacillus cereus?
A. Needs oxygen for growth
B. Absence of hemolysis on 5% sheep blood agar
C. It is encapsulated
D. Produces an exotoxin causing vomiting and diarrhea
A. Needs oxygen for growth
What toxin is responsible for binding of Clostridium difficile to the receptors on the brush border of the gut?
A. Alpha toxin
B. Toxin A
C. Theta toxin
D. Toxin B
B. Toxin A
Which of the following statements regarding Clostridium perfringens is correct?
A. It produces an endotoxin that causes tissue destruction
B. It produces non-hemolytic colonies with rough, uneven surface
C. It is the most common cause of antibiotic associated diarrhea
D. It is an anaerobic, gram positive bacilli
D. It is an anaerobic, gram positive bacilli
Case: A 70-year old male admitted for ~2 weeks in Intensive Care Unit (ICU).
Complaint: Sudden development of multiple episodes of diarrhea, hypotension, fever and cramping abdominal pain
History: On prolonged antibiotic use for pneumonia
Which of the following is the most likely cause of the patient’s problem?
A. Clostridium perfringens
B. Clostridium difficile
C. Bacillus cereus
D. Listeria monocytogenes
B. Clostridium difficile
