A 4-week-old black male child was transferred to your teaching hospital with a 10-day history of severe coughing spells. The illness had started with a "cold" but had gotten progressively worse in the last week. Before you go to the next frame, think about what diseases you would consider given this limited amount of information. You might want to jot them down on a piece of paper in order of their likelihood.
Question 1 - Single Best Answer
What are some causes/diseases you should be considering with this limited amount of information? Choose from the following list in the best order of priority.
1: pneumonia
2: meningitis
3: epiglottitis
4: meconium inhalation
5: cystic fibrosis
6: diphtheria
7: gonorrhea
8: congenital syphilis
9: whooping cough
10: rat bite fever
A) 2, 3, 8, 7, 9
B) 1, 9, 6, 8, 3
C) 1, 4, 6, 9,10
D) 4, 5, 8, 1, 3
Question 2 - Single Best Answer
Which of the following is the most likely bacterial cause of pneumonia in this age group?
A) Listeria monocytogenes
B) Group B Streptococcus (S. agalactiae)
C) Streptococcus pneumoniae
D) Chlamydia trachomatis
E) Pseudomonas aeruginosa
Note also that a number of viruses can cause respiratory infections/pneumonia in this age group. Included among these viruses are RSV, CMV, and parainfluenza viruses. Ureaplasma (a relative of Mycoplasma) is another agent that can cause respiratory problems in this age group.
Question 3 - Single Best Answer
What would you first look for to strengthen a diagnosis of pneumonia?
A) Gram positive cocci on a Gram stain of a lung aspirate
B) fluid infiltrates in the lung seen on an x-ray
C) sputum being coughed up
D) rales heard on auscultation
E) bacteria in a blood culture
Question 4 - Single Best Answer
What would be a defining characteristic of diphtheria?
A) severe coughing accompanied by apnea, cyanosis, and/or vomiting
B) a pseudomembrane in the throat
C) rales on auscultation
D) a stiff neck
E) a rash
Question 5 - Single Best Answer
What would you specifically look for to strengthen a diagnosis of whooping cough?
A) severe coughing accompanied by apnea, cyanosis, and/or vomiting
B) a pseudomembrane in the throat
C) rales on auscultation
D) a stiff neck
E) a rash
The baby's coughing was so violent that he often became cyanotic and gasped for breath when the coughing subsided. In addition, he had several episodes of vomiting associated with his coughing. You note that his pulse is quite rapid and that he is also breathing rapidly.
Question 6 - Single Best Answer
These findings (cyanosis and vomiting after coughing, rapid pulse and respiration) strengthen a diagnosis of?
A) pneumonia
B) whooping cough
C) diphtheria
D) epiglottitis
E) cystic fibrosis
Question 7 - Single Best Answer
You have listened to the chest and note that it is clear. What tests would you want to do to positively rule out pneumonia?
A) Gram stain of sputum
B) x-ray of chest
C) tuberculin test
D) lung aspiration
E) complete blood count and blood culture
The chest radiograph was clear. The white count was 15,500 with 70% lymphocytes. The hemoglobin was slightly low.
Question 8 - Single Best Answer
The clear chest and high white count with a preponderance of lymphocytes is consistent with a diagnosis of?
A) pneumonia
B) whooping cough
C) leukemia
D) cystic fibrosis
E) meconium aspiration
Question 9 - Single Best Answer
How would you confirm a diagnosis of whooping cough?
A) naso-pharyngeal swab; charcoal agar
B) throat swab; Gram stain
C) throat swab; blood agar
D) blood culture on Bordet-Gengou agar
E) naso-pharyngeal swab; chocolate agar under anaerobic conditions
After 7 days colonies of Bordetella pertussis were identified on the charcoal agar. This confirmed the presumptive diagnosis of whooping cough. Note that you should not wait for the results to start treating whooping cough! Note also that there are other agar plates used for Bordetella pertussis - Bordet-Gengou, for example.
Question 10 - Single Best Answer
How do you explain the preponderance of lymphocytes in whooping cough?
A) the pertussis toxin is a lymphocytosis promoting factor
B) the bacteria grows in the lymphocytes and turns on their reproductive machinery
C) the bacteria grows in the PMN's and kills them
D) the violent coughing causes high blood pressure and only the lymphocytes can survive
E) hypoxia stimulates lymphocytosis
Question 11 - Single Best Answer
What is/are the major virulence factor(s) of B. pertussis?
A) toxin, FHA (filamentous hemagglutinin), tracheal cytotoxin
B) IgA protease
C) pertussis toxin only
D) tracheal cytotoxin only
E) FHA only
Question 12 - Single Best Answer
What is the current strategy for immunization against whooping cough?
A) killed whole cell
B) DNA vaccine
C) pertussis toxoid plus FHA
D) tracheal cytoxin toxoid
E) There is no current vaccine.