Question 150
A 27-year-old male, who is a college instructor, presents to an acute care clinic with complaints of a productive cough for 3 days, a fever, and occasional difficulty breathing with exertion. He has no significant past medical history and does not smoke. A chest x-ray reveals consolidation of the lower lobe of the right lung. Of the following, what is the most likely etiology for his clinical presentation?
A. Bacterial infection
B. Parasitic infection
C. Mycobacterial infection
D. Aspiration
E. Neoplasm
Answer for Question 150
Answer: A (Bacterial infection)
Explanation: The presentation (short duration of productive cough, fever, and dyspnea) in an individual with no past medical history and with consolidation of one lung lobe is consistent with a lobar pneumonia, which, in this situation, would be a community-acquired bacterial infection, or possibly a community acquired viral infection, which can also have consolidation of a lung lobe on x-ray. Lobar pneumonia is often bacterial in origin, and most commonly Streptococcus pneumoniae. Given his history, Mycobacterium tuberculosis is unlikely (i.e., he is not homeless, or otherwise living under conditions likely to expose him to tuberculosis). He has no risk factor for aspiration; and given his young age and lack of smoking history, a pulmonary neoplasm would be very unlikely.
Question 151
A 33-year-old female, who is a nurse at the hospital, presents to an acute care clinic with complaints of a productive cough for 2 days associated with shaking chills. She also reports a fever of 38.5 degrees Celsius. She has no significant past medical history and does not smoke. Her heart rate is 105 bpm, her respiratory rate is 26 breaths per minute, and her blood pressure is 82/61 mmHg, which is lower than normal for her. A chest x-ray reveals consolidation of the lower lobe of the left lung. A blood culture is positive. Of the following, which condition in her past medical history would represent the most important risk factor for her current presenting condition?
A. Fracture of the left tibia three years ago while skiing
B. Remote splenectomy after abdominal trauma
C. Head injury following rock climbing fall
D. Past episode of deep venous thrombosis
E. History of acute rheumatic fever
Answer for Question 151
Answer: B (Remote splenectomy after abdominal trauma)
Explanation: The presenting features (productive cough and fever) combined with the x-ray results are consistent with a community-acquired pneumonia, which would likely be a lobar pneumonia in this case. The most common bacterial etiologic agent for a lobar pneumonia is Streptococcus pneumoniae. Individuals without a spleen are at increased risk for the development of a pneumococcal sepsis as the spleen plays a role in the production of antibodies against polysaccharides, which protect against encapsulated organisms. The other conditions would be play a significant role in her development of pneumonia or resultant sepsis.
Question 152
A 24-year-old male who has smoked since he was 14 years old but has no other past medical history presents to an acute care clinic in July with complaints of a productive cough and fever to 38.4 degrees Celsius for the past 4 days. Physical examination reveals dullness to percussion on the lower left side of the chest and crackles are heard at this location. Of the following, what is the most likely diagnosis?
A. Community-acquired pneumonia
B. Chronic bronchitis
C. Pulmonary thromboembolus
D. Bronchogenic carcinoma
E. Aspiration pneumonia
Answer for Question 152
Answer: A (Community-acquired pneumonia)
Explanation: The presentation (cough and fever) and physical examination (dullness to percussion and crackles) are consistent with a community-acquired pneumonia. While chronic bronchitis can present with a productive cough, patients would normally be afebrile and there would be no localizing physical examination findings (i.e., the dullness to percussion or crackles). While a pulmonary thromboembolus could, with infarction, lead to a region of dullness to percussion and crackles, and could have a fever, the productive cough would not be typical and the patient has no risk factors for deep venous thrombi. Even though he has a smoking history, a bronchogenic carcinoma would be rare at this age. While aspiration pneumonia could cause the signs and symptoms listed, the patient has no risk factors for aspiration (e.g., a neuromuscular disease, or drug/alcohol intoxication).