An 18-year-old healthy male had noted fatigue and some generalized muscle aches for several days. He awoke on the morning of October 31 (which he distinctly remembered as he had been planning to go to a Halloween Ball as an amoeba) feeling chilly and suffering from a sore throat and a severe frontal headache. He also felt hot, and recorded a temperature of 102. Over the next several days he became increasingly bothered by a persistent non-productive cough, along with his headache and fever. He also noted increasing severity of muscle aches and pains. On November 2, he complained of a severe left earache, and the next day consulted a physician.
Question 1 - Single Best Answer
Your differential diagnosis, at this point, would include which of the following?
A) meningitis, "strep" throat, flu, pneumococcal pneumonia, Legionnaire's disease
B) mycoplasma pneumonia, Rocky Mt. spotted fever, shigellosis
C) "walking" pneumonia, botulism, otitis media, psittacosis
D) mycoplasma pneumonia, "Strep" throat, flu, chlamydial pneumonia, otitis media
E) syphilis, gonorrhea, tetanus, dysentery, otitis media
The doctor determined that the young man lived alone and had no pets. He did not smoke and only very occasionally drank alcohol. He had a girlfriend with whom he had a monogamous relationship.
Your differential diagnosis correctly listed chlamydial pneumonia. Chlamydia can cause a lower respiratory tract infection that resembles "walking" pneumonia.
Question 2 - Single Best Answer
What species of Chlamydia would be most likely to cause pneumonia in this young man?
A) none, Chlamydia don't cause pneumonia, just pneumonitis
B) Chlamydia psittici
C) Chlamydia pneumoniae
D) Chlamydia trachomatis
Question 3 - Single Best Answer
The young man's age, and the fact that he did not smoke or drink would tend to rule out which of the following?
A) Legionnaire's disease
B) Strep throat
C) influenza
D) mycoplasma pneumonia
E) otitis media
Physical examination by the doctor revealed a temperature of 101 and a pulse rate of 105/min. Blood pressure was 124/76, and respirations were 24/min.
Question 4 - Single Best Answer
Of these values, which is/are abnormal?
A) temperature and blood pressure
B) only temperature
C) only pulse and respiration
D) temperature, pulse, and respiration
E) all of the values
The patient looked reasonably well but was obviously in pain because of the earache and the distressing and persistent dry cough. The left tympanic membrane was slightly erythematous. A single tender enlarged cervical lymph node was palpable below the left ear lobe.
Question 5 - Single Best Answer
The fact that the patient was reasonably well would tend to rule out which disease?
A) mycoplasma pneumonia
B) Legionnaire's disease
C) meningitis
D) pneumococcal pneumonia
E) several of the above
Question 6 - Single Best Answer
The earache is probably due to?
A) otitis media caused by S. pneumoniae (pneumococcus)
B) otitis media caused by H. influenzae
C) infection by Mycoplasma pneumoniae
D) referred pain from his "Strep" throat
E) a side effect of influenza virus mediated by interferon
Question 7 - Single Best Answer
What other tests would you do at this point?
A) throat culture
B) blood count
C) chest X-ray
D) auscultation of the chest
E) all of the above
Hematocrit was normal. Leucocyte count was 8000 cells per cubic millimeter, with a normal differential. No beta hemolytic colonies from the throat culture grew on blood agar.
Question 8 - Single Best Answer
The leucocyte count
A) indicates an oncogenic process
B) indicates an infectious disease
C) is normal
Question 9 - Single Best Answer
The lack of beta hemolytic colonies from the throat culture indicates?
A) he does not have influenza, as the flu virus produces beta hemolytic colonies on blood agar
B) he does not have otitis media caused by H. influenzae
C) he does not have a sore throat caused by Streptococcus pyogenes
D) he does not have mycoplasma pneumonia
E) he does not have Legionellosis
Examination of the chest revealed crackling inspiratory rales over the right lower lung field posteriorly.
Question 10 - Single Best Answer
The rales and their position indicate?
A) a normal state
B) bronchoconstriction
C) fluid in the trachea and bronchi
D) fluid in the lungs
X-ray showed a stringy, poorly delineated infiltrate in the most posterior and inferior segment of the right lower lobe.
A satisfactory sputum sample could not be obtained.
Question 11 - Single Best Answer
How does this X-ray differ from what would be seen with pneumococcal pneumonia?
A) The position of the infiltrate would be different
B) There would likely be more consolidation with pneumococcal pneumonia.
C) The infiltrate would be only interstitial in pneumococcal pneumonia
D) It is always bilateral in pneumococcal pneumonia
Question 12 - Single Best Answer
Most of the signs and symptoms indicate a diagnosis of mycoplasma pneumonia. The lack of a good sputum sample is one of the signs pointing to this diagnosis. Sometimes patients with this disease do produce some sputum, however. When they do, the following is seen on a Gram stain:
A) a few neutrophils and no bacteria
B) Gram positive cocci in bunches
C) Gram negative diplococci inside white cells
D) Gram positive lancet-shaped diplococci
Question 13 - Single Best Answer
How could you verify a diagnosis of Mycoplasma pneumonia?
A) aspirate the lung and grow the organism on blood agar - - it should be alpha hemolytic.
B) aspirate the lung and do dark field microscopy
C) look for cold hemaglutinnins in the patient's serum
D) look for a rise in complement-fixing antibodies to mycoplasma in the patients serum
E) both C and D are correct
Question 14 - Single Best Answer
What is a major virulence mechanism of Mycoplasma pneumonia?
A) intracellular growth
B) a polysaccharide capsule to prevent phagocytosis
C) an enzyme that hydrolyzes IgA
D) an adhesin on the tip of the organism called P1
E) a pilus adhesin
Question 15 - Single Best Answer
Would you prescribe penicillin for this disease?
A) yes
B) no
Question 16 - Single Best Answer
Penicillin would not work in this disease because?
A) the organism produces a beta lactamase
B) the organism produces a beta hemolysin
C) the organism makes fried egg colonies
D) the organism has no cell wall
E) the organism has sterols in its cell membrane
Question 17 - Single Best Answer
Where did the young man acquire the mycoplasma?
A) via sexual contact
B) from his normal flora
C) at the blood bank when he gave blood
D) from someone else with the disease via the respiratory route
E) from unpasteurized milk
Question 18 - Single Best Answer
In your book look up some of the other mycoplasma. One found in the G-U tract is?
A) M. avium intracellularae
B) M. hominis
C) M. salivarium
D) Ureaplasm urealyticum
E) two of the above