Microbiology - Chapter 19 - Connect, learn smart assignment

What species is responsible for a majority of the clostridial tissue and wound infections?

C. perfringens

What causes pseudomembranous colitis?

Clostridium difficile

Tetanus is caused by the bacterium ______ ______.

Clostridium tetani

The ways most cases of tetanus enter the body

- burns - accidental puncture wounds - crushed body parts - frostbite - umbilical stumps

chest x rays are used in the diagnosis of tb when:

- further verification of a positive test is required - other test give unclear results

steps involved in pulmonary anthrax infection

1. inhalation of spores into lungs 2. germination of spores into vegetative cells 3. secretion of exotoxins into circulation 4. phagocytosis of exotoxins by macrophages 5. release of chemical mediators/macrophage death

How does Clostridium tetani cause spastic paralysis of the muscles?

It releases a neurotoxin that blocks the inhibition of muscle contractions

A positive ______ test is a skin test that can provide evidence of either a recent or latent TB infection.

Mantoux

The screening test for tuberculin hypersensitivity is called the ______ test.

Mantoux

Unlike most pathogens, which bacteria does not produce exotoxins or enzymes that contribute to its virulence, instead relying on waxes and a cord factor to evade the immune system?

Mycobacterium tuberculosis

What is the most effective prevention fro clostridial wound infections?

Rigorous wound cleansing

______ is a neuromuscular disease that results in the uncontrolled contraction of skeletal muscles.

Tetanus

How are clostridial infections acquired?

They are acquired through contamination of injured skin

T/F: Antibiotic treatment for anthrax does not decrease the effects of the toxin.

True

T/F: Like tuberculosis, the majority of people that come into contact with the leprosy bacillus do not develop clinical disease.

True

T/F: The incidence of leprosy has been decreasing world wide

True

Tuberculosis in normal, untreated cases... a. progresses quickly b. progresses slowly c. will have alternating periods of illness and health d. can persist for a lifetime e. will cause constant illness

b. progresses slowly c. will have alternating periods of illness and health d. can persist for a lifetime

Which of the following describe the characteristics of Clostridium? a. catalase-positive b. rods c. cocci d. catalase-negative e. gram-negative f. gram-positive

b. rods d. catalase-negative f. gram-positive

Which of the following is NOT usually used in drug therapy for TB? a. Ethambutol b. Isoniazid c. AZT d. Streptomycin e. Rifampin

c. AZT

Which of the following is used to determine success of drug treatment against TB infection? a. disappearance of tubercles b. decreased antibody titer to bacillus in serum c. decrease of acid-fast bacteria in smear

c. decrease of acid-fast bacteria in smear

Tuberculin skin testing is positive or inconclusive, a ______ x-ray will help verify a diagnosis.

chest

Clostridial diseases are often caused by: a. direct cellular action b. release of endotoxin c. release of pyrogens d. release of exotoxins

d. release of exotoxins

Which of the following is NOT a reason why a false negative TB skin test may occur? a. patient has compromised immune system b. person is infected but not reactive c. administer too early in course of infection d. vaccination with BCG vaccine

d. vaccination with BCG vaccine

The surgical removal of diseased tissue is called _______

debridement

The mode of transmission for TB is via

droplets

An ______ formed in a vegetative cell has extreme resistance to heat, drying, radiation and chemicals.

endospore

______ botulism is due to the ingestion of pre-formed toxin, whereas ______ is due to the germination of Clostridium botulinum spores in the GI tract.

food-borne, infant

What are two general symptoms seen in gas gangrene?

gas production by bacteria necrosis of tissue

Members of the genus Clostridium are ______ - ______ ______.

gram-positive rods

Testing for TB is now focused on selected groups known to have _____ risk for TB?

higher

The BCG vaccine for TB is highly ______ in adults.

ineffective

Tetanus is also known as _______ because is cases uncontrolled contraction of the muscles in the face.

lockjaw

Treatment for TB requires drug therapy for 6-24 ______.

months

MDR-TB

multidrug-resistant tuberculosis

Clostridium perfringens is considered to be an:

obligate anaerobe

What conditions favor germination of C. tetani spores?

poor blood supply to tissue necrotic tissue

BCG vaccination and infection with other Mycobacteria may lead to a false ______ TB skin test.

positive

Most endospore-forming bacteria are also Gram-______ and ______-shaped.

positive; rod

Spores of Bacillus cereus survive cooking and germinate to release enterotoxins when food is stored at ______ temperature.

room

Acid-fast staining of ______ or other specimens can be conducted to verify positive skin tests or chest x-rays in the diagnosis of TB.

sputum

clostridial diseases are often caused by

the release of exotoxins

How do B. anthracis endospores enter the body in pulmonary anthrax?

through inhalation

T/F: Clostridial exotoxins are among the most poisonous substances on earth

true

Pulmonary TB is indicated when ______ are seen on a chest x-ray.

tubercles

What is seen on a chest X-ray that indicates pulmonary TB?

tubercles

Skin testing to determine tuberculosis exposure uses ______ injected under the skin

tuberculin

Where in the human body are the spores of C. perfringens typically found?

vagina intestine skin

How is wound botulism transmitted?

via puncture wounds, in a similar manner to tetanus

The ingestion of B. cereus toxin in foods leads to what symptoms?

vomiting diarrhea

Which of the following is not a characteristic of endospores? - resistance to physical control - active metabolism - resistance to chemical control - pathogenic

- active metabolism

What is used to control the spread of tuberculosis in the hospital?

- negative pressure rooms - UV lamps

How is the tuberculin reaction test read by clinicians?

- observation of skin for indurations

Which of the following are characteristic of the genus Bacillus? - gram negative - saprobic - anaerobic - source of antibiotics - aerobic - endospore-forming

- saprobic - source of antibiotics - aerobic - endospore-forming

a negative tuberculin skin test may indicate

- that an individual has not had any contact with tuberculosis - that a person has been infected but has not yet reacted

Drug resistance of the tubercle bacillus is overcome by:

- using at least 2 drugs in combination

What represent the two major categories of clostridial disease?

- wound/tissue infections - food intoxications

______ is a zoonotic disease caused by Bacillus anthracis which has different manifestations of human disease depending on the portal of entry.

Anthrax

The ______ vaccine is used to prevent TB.

BCG

The causative agent of anthrax is

Bacillus anthracis

______ is caused by a species of Clostridium and causes flaccid muscle paralysis

Botulism

T/F: Leprosy does not occur in the US.

False

T/F: It is only important to seek out and treat those persons with active TB.

False These in early stages of infection AND those at high risk should be treated as well.

The majority of tetanus cases in the US occurs in what two groups of people?

IV drug users elderly

______ botulism is caused by ingestion of the C. botulinum spores.

Infant

Which of the following apply to tuberculosis? a. approx 1/3 of the worlds population is infected with Mycobacterium tuberculosis. b. approx 1/3 of those infected develop TB disease c. about 5-10 percent of those infected develop TB disease d. humans are easily infected

a. approx 1/3 of the worlds population is infected with Mycobacterium tuberculosis. c. about 5-10 percent of those infected develop TB disease d. humans are easily infected

Infection with the TB bacterium leads to which type of hypersensitivity to tuberculoprotein? a. cell mediated b. immune complex c. immediate d. cytotoxic e. delayed

a. cell-mediated b. delayed

Which of the following are factors that predispose a person to developing clinical leprosy? a. genetic markers b. living conditions c. defect in antibody production d. health of patient e. defect in T-cell regulation f. confection with tuberculosis

a. genetic markers b. living conditions d. health of patient e. defect in T-cell regulation

Which of the following factors increase the chances that a person will develop clinical leprosy? a. living in crowded conditions b. being a long-term household contact of a leprosy patient c. co-infection with tuberculosis d. having poor nutrition e. being vaccinated with BCG

a. living in crowded conditions b. being a long-term household contact of a leprosy patient d. having poor nutrition

Which of the following characteristics can differentiate between the genera Bacillus and Clostridium? a. presence of catalase b. oxygen requirements c. gram stain reaction d. cell morphology

a. presence of catalase b. oxygen requirements

A positive tuberculin skin test can indicate: a. reactivation of a prior latent infection b. an allergy to tuberculin c. that a patient is immune to tuberculosis d. extra pulmonary tuberculosis e. a recent exposure to tuberculosis f. vaccination with the BCG vaccine

a. reactivation of a prior latent infection e. a recent exposure to tuberculosis f. vaccination with the BCG vaccine

Which of the following are characteristic of the genus Bacillus? a. source of antibiotics b aerobic c. endospore-forming d. saprobic e. anaerobic f. gram-negative

a. source of antibiotics b aerobic c. endospore-forming d. saprobic

Who should be treated for TB? a. those with active TB b. those who are at high risk of becoming infected c. those with latent TB d. laboratory workers who are frequently in contact with the bacillus

a. those with active TB b. those who are at high risk of becoming infected c. those with latent TB

What factors are required for clostridial infection?

anaerobic conditions damaged tissues

What animal is known to be a reservoir of the leprosy bacillus?

armadillos