John Dough has come to your clinic because he has been bothered by a cough for the last several months. He has no other complaints except fatigue, and has not been sick for at least a year. He is a 35-year-old white man. He used to work as a baker's assistant, but problems with alcohol caused him to lose his job as well as his family, and now he lives in and out of homeless shelters. He tells you that he feels somewhat warm, so thinks he has a fever, but has not had access to a thermometer to take his temperature. At night he gets especially hot, and sometimes wakes up in a sweat. You note that he is somewhat thin and ask him if he has always been so. He replies that he hasn't kept very good track of his weight, but that his clothes seem to be looser than they used to be so maybe he has lost some weight.
Question 1 - Single Best Answer
A large number of both infectious and non-infectious causes can be responsible for a chronic cough that has not been preceded by an acute illness. Which of the following would you think are MOST likely? Bugs Database
Legionella pneumophila, Streptococcus pneumoniae, Mycobacterium tuberculosis Chlamydia pneumoniae, Mycoplasma pneumoniae, Klebsiella pneumoniae Mycobacterium tuberculosis, Mycoplasma pneumoniae, Bordetella pertussis Mycoplasma pneumonia, Influenza virus, Rhodococcus equi Mycobacterium tuberculosis, Rhodococcus equi, Actinomyces israeli
While he is talking to you, he has a short coughing spell and you note that he has coughed up some blood. You also note that he is dyspnoeic at rest.
Question 2 - Single Best Answer
Which organism is most likely to cause frankly bloody sputum? Bugs Database
Streptococcus pneumoniae Mycobacterium tuberculosis Klebsiella pneumoniae Influenza virus Rhodococcus equi
Question 3 - Single Best Answer
Which organism causes "rust" colored sputum? Bugs Database
Question 4 - Single Best Answer
Which organism causes "currant jelly" sputum? Bugs Database
Question 5 - Single Best Answer
What test could you do that would immediately indicate, if positive, that he had TB? Bugs Database
Gram stain of throat swab Gram stain of sputum acid-fast stain of sputum Australia antigen Koplik spots
Question 6 - Single Best Answer
What other tests would you order? Bugs Database
Chest x-ray PPD CBC all of the above
A few acid fast rod-shaped bacteria were seen in his sputum sample. You must await the results of the other tests.
Question 7 - Single Best Answer
What were the acid-fast rods that were seen? Bugs Database
Mycobacterium kansasii Mycobacterium avium-intracellulare complex Mycobacterium leprae Mycobacterium tuberculosis strictly speaking, it is impossible to tell
The next day you received the following test results:
Question 8 - Single Best Answer
Which of the test results are normal? Bugs Database
Chest x-ray haemoglobin WBC erythrocyte sedimentation rate none of the above
Question 9 - Single Best Answer
What result would you expect, based on the finding of acid-fast bacteria, from the PPD test, and when? Bugs Database
redness and swelling (}10mm) at the site of injection after 12 hours redness and swelling (}10mm) at the site of injection after 24 hours redness and swelling (}10mm) at the site of injection after 3 days no reaction at the site of injection
Question 10 - Single Best Answer
If this (redness and swelling at the site of injection after three days) was the result in an individual not demonstrating any acid-fact bacteria (AFB) in a good sputum sample, what would it mean? Bugs Database
the individual definitely does not have active disease, it is an immunological cross-reaction the individual has active TB now, but has not had it in the past he has received BCG the individual has been infected but has no active disease either C or D is correct
Question 11 - Single Best Answer
What is the pathogenesis of the lesion seen on the x-ray? Bugs Database
a granuloma with central (caseous) necrosis an inflammatory response with edema fluid nitrous oxide killing of the bacteria one lobe completely filled with fluid a tumor
The PPD test, read on the third day, shows less than 5mm of induration.
Question 12 - Single Best Answer
Does this (less than 5mm redness and swelling at the site of injection of the PPD) mean that Mr. Dough does not have infection by Mycobacterium tuberculosis? Bugs Database
yes no
Question 13 - Single Best Answer
What other tests should have been or should now be done? Bugs Database
hypersensitivity to Candida albicans HIV antibody Culture of M. tuberculosis hypersensitivity to penicillin A, B, C
Question 14 - Single Best Answer
When would you start antimicrobial therapy for this patient? Bugs Database
After a culture has confirmed that he has TB After a repeat PPD test that is positive After acid-fast bacteria were seen in his sputum After the results of his HIV test, because this will effect the type of therapy he gets
Question 15 - Single Best Answer
What would the recommended therapy be? Bugs Database
penicillin and streptomycin isoniazid alone isoniazid plus ethambutol isoniazid plus rifampin isoniazid plus rifampin plus pyrazinamide
Question 16 - Single Best Answer
How long is a course of TB therapy? Bugs Database
until his PPD test is negative one month 6-18 months five years forever
Question 17 - Single Best Answer
Which of the following is a big problem in treating TB? Bugs Database
teaching patients to administer the drugs intravenously side effects of the drugs which include mental instability patient compliance
The culture was positive for M. tuberculosis after 28 days. He had a very weak reaction to the Candida antigen, and he was HIV positive.
Question 18 - Single Best Answer
How is M. tuberculosis grown? Bugs Database
the footpad of the armadillo anaerobically on nutrient broth agar in 5% carbon dioxide at room temperature in 5% carbon dioxide at 37 degrees on Lowenstein-Jensen medium In cultures of human macrophages
Question 19 - Single Best Answer
What most likely was the immediate source of Mr. Dough's (active) TB infection? Bugs Database
a sexual partner contaminated food the air in the homeless shelter reactivation of a previous infection
Question 20 - Single Best Answer
What are some things that might have caused the reactivation of the TB? Bugs Database
homelessness alcoholism HIV malnutrition all of the above
Question 21 - Single Best Answer
When Mr. Dough was originally infected with TB, what was the most likely route of the infection? Bugs Database
respiratory fecal-oral sexual insect vector ingestion
Question 22 - Single Best Answer
When Mr. Dough was first infected with TB, what would his symptoms have been? Bugs Database
essentially the same as they are now a cough, but with no hemoptysis a high fever, but no cough he probably would have had no symptoms at all
Question 23 - Single Best Answer
If Mr. Dough had not been HIV positive, what is the most likely thing that would have been seen in his chest x-ray? Bugs Database
his chest would have been normal interstitial infiltrates consolidation a cavitary lesion
Question 24 - Single Best Answer
In what populations is it most likely that TB will be symptomatic on first exposure? Bugs Database
pregnant women and babies babies and AIDS pts alcoholics and homosexuals asthmatics and diabetics people who have not been vaccinated with BCG
Question 25 - Single Best Answer
Which of the following are virulence factors/mechanisms for M. tuberculosis? Bugs Database
cytotoxin superantigen toxin antigenic variation spores intracellular growth
Question 26 - Single Best Answer
Disease manifestations in TB are largely the result of which of the following? Bugs Database
cytotoxicity immunosuppression cellular immune response antigenic cross reactivity
Question 27 - Single Best Answer
Problem(s) in combatting TB during the last five years of the 20th century and into the 21st century will likely be? Bugs Database
antibiotic resistance increased number of AIDS patients increased numbers of people living in poverty and crowded conditions lack of a good vaccine all of the above