Respiratory Medicine - Pulmonology MCQs 3 For Medical Exam Preparation

Respiratory Medicine 3 - Pulmonology MCQs For Medical Exam Preparation

A 16 year old healthy boy suddenly develops severe left sided chest pain while walking. The pain is sharp and increases with inspiration, but denies tenderness over the chest wall or left shoulder pain. His respiratory rate is 20, his heart rate is 110, his blood pressure is 125/90mmHg and he is sweating slightly. No murmurs or thrills are appreciated on physical examination. The most likely diagnosis is

A. Muscle strain.

B. Pneumothorax. ✅

C. Angina.

D. Pleurodynia.

E. Aortic stenosis.

Question Explanation:

Spontaneous pneumothorax in the young healthy adult is fairly common and is associated with occult blebs which may rupture without relation to exercise. A "pulled muscle", resulting in severe and persistent chest pain, will usually be obviously related to local exertion by the patient. Pleurodynia occurs mainly in children and includes other symptoms of illness including fever; its onset is not associated with exertion. While angina can occur in the adolescent or young adult, it is rare and not associated with respiration. Aortic stenosis generally is not symptomatic in the adolescent and, in non-mild cases, produces thrills and other abnormalities on physical examination.

A 12 year old boy has chronic cough. He has just recovered from his fourth bout of pneumonia in the past 5 months. On examination, digital clubbing, hyperresonance to percussion, and basilar crackles are noted. His sweat chloride concentration is 87mEq/L. What agent would most likely serve to alleviate his chronic signs and symptoms?

A. Dextromethorphan (PO)

B. Ipratropium (aerosolized)

C. N-acetylcysteine (aerosolized) ✅

D. Pentamidine (aerosolized) 

E. Vancomycin (IV) 

Question Explanation:

The patient is presenting with signs and symptoms of cystic fibrosis (CF). CF is an autosomal recessive disorder of the exocrine glands. The pulmonary manifestations include acute and chronic bronchitis bronchiectasis, chronic bouts of pneumonia hemoptysis, and cor pulmonale, which can occur late in the disease. 

Other common findings include chronic cough, exercise intolerance, recurrent respiratory infections, digital clubbing, increased anteroposterior diameter, and basilar crackles. It the pilocarpine sweat test reveals sodium and chloride levels greater than 80mEq/L, a diagnosis of CF can be made. The primary goals of treatment include thinning the mucus secretions, keeping the airways open, and treating recurrent infections. Thinning of mucus can be achieved with mucolytics such as N-acetylcysteine. N-Acetylcysteine (Mucomyst) splits the disulfide linkages between these mucoproteins, resulting in a decrease in mucous viscosity. It is indicated as adjuvant therapy in the treatment of abnormal viscid or inspissated mucus secretions in CF, chronic lung disease, post traumatic chest complications and atelectasis secondary to mucus obstruction inhaled bronchodilators are used to open the airways. 

Furthermore prednisone has been shown to increase pulmonary function and increase bodyweight. The definitive treatment is lung transplantation. Dextromethorphan, a cough suppressant, is contraindicated in patients with CF since it will prevent the removal of mucus from the lungs. Ipratropium is an anticholinergic that will cause a drying and thickening of the mucus in this patient; therefore, it is contraindicated. 

Pentamidine (aerosolized) is an antiprotozoal agent primarily used in the treatment of Pneumocystis carinii pneumonia in HIV-infected patients. Vancomycin is an anti- infective agent used in the treatment of life threatening, gram-positive infections.

A 48 year old man presents with oliguria, elevated blood area nitrogen and creatinine and hematuria. Nasal congestion and epistaxis are also present. Systemic review is notable for occasional cough and hemoptysis. On exam mucosal ulceration and nasal septal perforation is present, but no polyps are seen. What serum markers would likely be present in this case?

A. Anticentromere antibody

B. Anti-Ro

C. Anti-SS-B

D. C-ANCA ✅

E. Decreased erythrocyte sedimentation rate

Question Explanation:

This patient has Wegener granulomatosis, which is characterized by renal involvement, severe upper respiratory tract symptoms, and pulmonary involvement. Other organ systems may also be involved. The renal syndrome is a crescentic, rapidly progressive glomerulonephritis leading to renal failure. The upper respiratory tract findings include sinus pain and drainage, and purulent or bloody nasal discharge with or without nasal ulcerations. Nasal septal perforation may follow.

Pulmonary involvement may be clinically silent with only infiltrates present on X- ray, or it may present as cough and hemoptysis. ANCA stands for antineutrophil cytoplasmic antibody, and c- ANCA refers to antibody that localizes staining to the cytoplasm of neutrophils. The most common target antigen is proteinase 3 (PR 3). C-ANCA is a marker for Wegener granulomatosis, present in a high percentage of patents.

Anticentromere antibody is associated with approximately 90% of cases with CREST syndrome (calcinosis, Raynaud phenomenon, esophageal motility syndrome, clerodactyly, and telangiectasia), which is also called limited systemic sclerosis. Anti-Ro is also called anti-SS-A and is associated with Sjogren syndrome (70 to 95%). Anti-SS-B is associated with Sjogren syndrome (60 to 90%). Decreased erythrocyte sedimentation rate (ESR) is not a marker of Wegener. Instead, a markedly elevated ESR is seen. Additionally, mild anemia thrombocytosis, leukocytosis, mild hypergammaglobulinemia (IgA), and mildly elevated rheumatoid factor are seen in this disorder.

A 59 year old man who is being treated for COPD now presents with an upper respiratory tract infection. He is currently taking theophylline. The man presents to the emergency department 5 days later complaining of persistent tachycardia, insomnia, and agitation. What antibiotic was most likely prescribed for the treatment of his infection?

A. Amoxicillin

B. Cefaclor

C. Chloramphenicol

D. Doxycycline 

E. Erythromycin ✅

Question Explanation:

Theophylline is a xanthine derivative that relaxes smooth muscle by a direct action. The smooth muscle in the

bronchi and pulmonary vessels are particularly affected. This agent also stimulates the respiratory center. Theophylline is often used for prophylaxis and symptomatic relief of bronchial asthma and chronic obstructive pulmonary disease (COPD). This agent is extensively metabolized by the CYP450 system in the liver; therefore, any agent that inhibits the liver's ability to metabolize theophylline would increase its level in the blood. This would subsequently potentiate the effects, as well as the adverse effects of theophylline. Erythromycin is a macrolide antibiotic commonly used in the treatment of upper respiratory and skin/subcutaneous infections. It is a relatively potent hepatic microsomal enzyme inhibitor. Since erythromycin is likely to potentiate the effects of theophylline, it could account for this patient's symptoms. The other agents do not interact with theophylline. Amoxicillin is a penicillin antibiotic used to treat a variety of infections caused by many different organisms. Cefaclor is a second generation cephalosporin used commonly to treat upper and lower respiratory infections. Chloramphenicol is an antibiotic used to treat severe infections when less toxic agents cannot be used. Doxycycline is a tetracycline antibiotic commonly used to treat acne and various sexually transmitted diseases.

A 48 year old woman has easy bruisability, cutaneous striae and excessive hair growth on her face. She has been smoking 1 pack of cigarette a day for 8 years. Her BP is 150/90 mmHg. She has elevated cortisol levels, which are not suppressed when she is given high dose dexamethasone. ACTH levels are high. After confirmation of the diagnosis, which one is the preferred treatment?

A. Adrenalectomy

B. General support only

C. Mitotane

D. Pneumonectomy

E. Radiation and chemotherapy direct at lung cancer ✅

Question Explanation:

The endocrine workup is indicative of ectopic ACTH production, and the most likely site is small cell carcinoma of the lung. If the high dose dexamethasone suppression test had suppressed 50% or more of the ACTH, then the most likely cause would be a primary pituitary adenoma (Cushing disease). In this patient however, the ACTH was not suppressed; therefore, this is suspicious for an ectopic ACTH producing tumor, either in the lung or the adrenals. The next step in diagnosis is to check the ACTH levels; if lower then normal, the most likely cause for the ectopia would be an adrenal neoplasm. But if the ACTH is higher than normal (as in this case), the most likely cause for the ectopia would be lung neoplasia (specifically small cell carcinoma). The lung cancer is what is going to kill this woman, not the endocrine manifestations of the tumor. 

Small cell carcinoma is considered to be inoperable because it is a rapidly growing tumor that metastasizes early and has an overall poor prognosis. Longer survival can be obtained with radiation and chemotherapy. Adrenalectomy (A) would address the endocrine problem by depriving the ectopic ACTH of its target gland. But the lethal disease here is the lung cancer that is causing the paraneoplastic syndrome, not an adrenal adenoma. Adrenalectomies are quite useful, and often curative in patients who have an established unilateral adrenal adenoma. Bilateral adrenalectomy is required for bilateral micronodular and most patients with macronodular adrenal hyperplasia. General support only (B) would lead to death in about 2 months. Radiation and chemotherapy can prolong survival by approximately 2 years.

Mitotane (C) is incorrect. Adrenal carcinomas producing ectopic ACTH almost invariably recur and usually do not respond to either irradiation or chemotherapy Mitotane offers such patients the only hope of cure. In patients with inoperable, residual, or recurrent adrenal neoplastic disease, it is usually palliative and does not prolong life. In patients with Cushingoid features, after the high dexamethasone fails to suppress ACTH, the ACTH levels should be taken to differentiate lung cancer versus adrenal adenomas as the cause of the ectopic ACTH. This patient has an increased ACTH level, which indicates that the likely origin of the ectopia is a lung neoplasia, not an adrenal one. Mitotane is not used for ACTH producing lung neoplasia.

Pneumonectomy (D) is not the treatment for small cell carcinoma of the lung. It is the appropriate treatment for resectable and potentially curable non small cell cancers of the lung.

A 37 year old woman was successfully treated for Pneumocystis jirovecii pneumonia. She was re-admitted with acute breathlessness with left sided chest pain 10 days after discharge. Exam revealed hypoxia and she was found to have diminished breath sounds on the left side of chest. The likely cause of her recent admission is which one of the following?

A. Acute myocardial infarction

B. Acute pericarditis

C. Acute pulmonary embolism

D. Left lobar pneumonia

E. Pneumothorax ✅

Question Explanation:

Pneumothorax is a well-known complication of PCP. An acute history of chest pain with breathlessness and diminished breath sounds is typical of pneumothorax.

Diminished breath sounds are not a feature of acute myocardial infarction or acute pericarditis. Acute pulmonary embolism should be considered due to her recent admission but diminished breath sounds are not a feature. There are no signs of consolidation to consider lobar pneumonia.

A 41-year-old male has bronchiectasis. He is breathless and is a victim of recurrent infections. Inspiratory crackles are present. Which of the following is likely to decrease the frequency of his exacerbations?

A. Postural drainage ✅

B. Cyclical antibiotic therapy

C. Inhaled corticosteroids

D. Vitamin supplements

E. Pancreatic enzyme replacements

Question Explanation:

As this patient has Bronchiectasis, he will have regular production of sputum associated with breathlessness, repeated lung infections and the signs of Inspiratory bilateral crackles are present. Retained mucus is the most important reason why bronchiectatic patients become infected. Postural drainage is therefore the cornerstone to treating bronchiectasis and should be undertaken at least once per day and more frequently during exacerbation.

There have been trials looking at regular antibiotic therapy versus symptomatic treatment in patients with cystic fibrosis colonized with pseudomonas but there is currently no evidence that this approach is of benefit in bronchiectasis. Similarly inhaled corticosteroids should not be used routinely in bronchiectasis until further evidence of their effect on lung function and exacerbation frequency is available. Surgical resection as a curative procedure can be performed for localized disease when underlying causes such as primary ciliary dyskinesia have been excluded. In this patient the bilateral crackles suggests widespread disease.

What sign is consistent with an overdose of morphine?

A. Tremulousness

B. Nystagmus

C. Mydriasis

D. Hypertension

E. Respiratory depression ✅

EXPLANATION

Respiratory depression is the chief hazard of all morphine preparations. Respiratory depression occurs more frequently in elderly or debilitated patients and in those suffering from conditions accompanied by hypoxia, hypercapnia, or upper airway obstruction in whom even moderate therapeutic doses may significantly decrease pulmonary ventilation. 

Acute overdosage with morphine is manifested by respiratory depression, somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin and constricted pupils.

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