Question 6
A 36-year-old woman has had increasing dyspnea for 8 years. She has no cough or increased sputum production. On physical examination there is hyperresonance to percussion. A chest radiograph reveals increased lung volumes with flattening of the diaphragmatic leaves bilaterally. The right heart border is prominent. A chest CT scan demonstrates decreased attenuation in all lung fields. Which of the following laboratory findings is she most likely to have?
A Decreased serum ceruloplasmin
B Increased sweat chloride
C Elevated blood ethanol
D Decreased serum alpha-1-antitrypsin
E Positive urine opiates
F Positive antinuclear antibody test
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(D) CORRECT. AAT deficiency leads to lack of an anti-protease, which leads to development of emphysema, typically a panlobular type affecting lower lobes more severely.
(A) Incorrect. Wilson disease affects the liver and the CNS.
(B) Incorrect. Though cystic fibrosis commonly affects the lungs, it leads to the obstructive lung disease known as bronchiectasis.
(C) Incorrect. Alcoholism does not lead to emphysema (but many alcoholics also smoke).
(E) Incorrect. Intravenous drug users are at greater risk for infections and abscesses. The injected talc may form small foreign body granulomas in lung.
(F) Incorrect. A positive ANA can be associated with autoimmune diseases such as SLE. There is often type III hypersensitivity with deposition of antigen-antibody complexes at basement membranes, producing serositis and effusions, such as pleural effusions.
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Question 7
A 55-year-old man with a 55 pack year history of smoking cigarettes has recently experienced an episode of hemoptysis along with his usual cough. On physical examination there are no abnormal findings. He has a sputum cytology examination performed that on microscopic examination shows atypical cells with hyperchromatic nuclei and orange-pink cytoplasm. Labortory studies show a serum calcium of 11.3 mg/dL, with phosphorus 2.1 mg/dL. Which of the following chest radiographic findings is this man most likely to have?
A Large hilar mass
B Pneumonia-like consolidation
C Peripheral nodule
D Carinal compression
E Left pleural thickening
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(A) CORRECT. Both squamous cell and oat cell carcinomas tend to be central in location. Squamous cell carcinomas of the lung are associated with hypercalcemia, though overall the oat cell carcinomas are best known for paraneoplastic syndromes.
(B) Incorrect. This is more typical of a bronchioloalveolar carcinoma.
(C) Incorrect. Such a peripheral mass would more likely be a granuloma, an adenocarcinoma or a hamartoma.
(D) Incorrect. The carina is an unusual site for a primary tumor.
(E) Incorrect. The findings do not suggest a mesothelioma.
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Question 8
During a cardiac arrest, a 58-year-old man, a non-smoker, receives cardiopulmonary resuscitative measures and is brought to the hospital, where he is intubated. During the intubation procedure he suffers aspiration of gastric contents (pasta with mushrooms and peas). Over the next 10 days he develops a non-productive cough along with a fever to 37.9 C. A chest radiograph reveals a 4 cm diameter mass with an air-fluid level in the right lung. A sputum gram stain reveals mixed flora. Which of the following conditions is he most likely to have?
A Squamous cell carcinoma
B Lung abscess
C Chronic bronchitis
D Bronchiectasis
E Bronchopulmonary sequestration
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(B) CORRECT. A Lung abscesses can result from aspiration of oropharyngeal or nasopharyageal contents, where bacterial organisms as part of normal flora can be picked up and transported to the lungs. The straighter bronchus to the right lung is more likely to conduct aspirated material. With septicemia, multiple abscesses are more likely to be present.
(A) Incorrect. There is no propensity for a lung carcinoma, either primary or metastatic, to be in one lung or another. Lung cancers may have central cavitation if large, but usually not an air-fluid level. Large neoplasms can cause obstruction with pneumonia distal to the neoplasm.
(C) Incorrect. Chronic bronchitis is a clinical diagnosis made when a patient has a chronic productive cough.
(D) Incorrect. Bronchiectasis can occur from bronchial inflammation and destruction following obstruction and/or infection; cystic fibrosis is the best known disease to produce a widespread pattern of bronchiectasis. With obstruction, it depends upon the cause for the obstruction where the focus of bronchiectasis will be.
(E) Incorrect. Sequestrations are masses of lung tissue without a normal connection to the airways. They act as space occupying lesions and can cause obstruction.
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Question 9
A 66-year-old woman has had a worsening non-productive cough with malaise for the past week. Her temperature increases to 37.4 C. A chest radiograph reveals diffuse bilateral pulmonary interstitial infiltrates in all lung fields. A sputum gram stain reveals normal flora and few neutrophils. She recovers over the course of the next two weeks without sequelae. Infection with which of the following organisms most likely caused her illness?
A Mycobacterium tuberculosis
B Streptococcus pneumoniae
C Influenza A virus
D Cryptococcus neoformans
E Mycobacterium avium-complex
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(C) CORRECT. The typical appearance of a viral lung infection is chronic interstitial inflammation.
(A) Incorrect. TB most often produces a granulomatous pattern of inflammation with reticulonodular densities, particularly in the upper lobes.
(B) Incorrect. Pneumococcus leads to alveolar filling with neutrophils.
(D) Incorrect. Cryptococcus leads to granulomatous disease.
(E) Incorrect. MAI may produce poorly-formed granulomas.
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Question 10
A 58-year-old man has developed a non-productive cough worsening over the past 2 months. Last week he noted the appearance of blood-streaked sputum. On physical examination there are some expiratory wheezes auscultated over the left lung. A chest radiograph reveals a 5 cm mass near the left lung hilum. A sputum cytology reveals the presence of small clusters of very hyperchromatic, pleomorphic cells with scant cytoplasm. Which of the following is the most likely predisposing factor to development of his pulmonary disease?
A Silicosis
B Radon gas exposure
C Smoking
D Asbestosis
E Passive smoking
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(C) CORRECT. Smoking remains the most frequent cause of lung cancer. Lung cancer does, however, occur in nonsmokers. A small cell anaplastic carcinoma, as in this patient, is virtually always seen in smokers.
(A) Incorrect. Silicosis increases the risk for lung cancer slightly by about 2 fold.
(B) Incorrect. Radon is probably the second leading cause of lung cancer. However, most cases of lung cancer in which exposure to radon gas has been identified also occur in smokers.
(D) Incorrect. However, asbestos exposure increases the risk for lung cancer in smokers even more.
(E) Incorrect. Passive smoking could probably be right behind radon exposure as the second leading cause for lung cancer.
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