Question 1:
A 65-year-old male smoker presents with a productive cough, fever, and left-sided chest pain. Chest X-ray shows lobar consolidation. What is the most likely causative organism?

A) Mycoplasma pneumoniae
B) Streptococcus pneumoniae
C) Legionella pneumophila
D) Chlamydophila pneumoniae
E) Haemophilus influenzae

Question 2:
Which of the following is the most common cause of community-acquired pneumonia in adults?

A) Streptococcus pneumoniae
B) Mycoplasma pneumoniae
C) Haemophilus influenzae
D) Staphylococcus aureus
E) Klebsiella pneumoniae

Question 3:
A 30-year-old female presents with dry cough, fever, and bilateral infiltrates on chest X-ray. She recently returned from a bird-watching trip. What is the most likely diagnosis?

A) Tuberculosis
B) Pneumocystis jirovecii pneumonia
C) Histoplasmosis
D) Psittacosis
E) Sarcoidosis

Question 4:
In patients with suspected tuberculosis, which of the following is the most sensitive diagnostic test?

A) Chest X-ray B) Sputum smear microscopy
C) Sputum culture
D) Tuberculin skin test
E) Interferon-gamma release assay

Question 5:
A 40-year-old male with HIV infection presents with fever, dry cough, and shortness of breath. Chest X-ray shows bilateral interstitial infiltrates. What is the most likely causative pathogen?

A) Streptococcus pneumoniae
B) Pneumocystis jirovecii
C) Mycobacterium tuberculosis
D) Legionella pneumophila
E) Aspergillus fumigatus

Question 6:
Which of the following is a characteristic radiographic feature of primary pulmonary tuberculosis?

A) Cavitary lesions in the upper lobes
B) Bilateral interstitial infiltrates
C) Ghon complex
D) Pleural effusion
E) Miliary pattern

Question 7:
A 50-year-old male presents with fever, productive cough, and night sweats. He has a 20-pack-year smoking history. A chest CT shows a cavitary lesion in the right upper lobe. What is the most likely diagnosis?

A) Lung cancer
B) Tuberculosis
C) Bacterial lung abscess
D) Nocardiosis
E) Histoplasmosis

Question 8:
Which of the following is the most appropriate initial empirical antibiotic therapy for hospital-acquired pneumonia?

A) Amoxicillin
B) Ceftriaxone
C) Vancomycin
D) Piperacillin-tazobactam
E) Azithromycin

Question 9:
A 20-year-old college student presents with low-grade fever, headache, and a dry cough. Chest X-ray reveals patchy infiltrates. What is the most likely causative agent?

A) Streptococcus pneumoniae
B) Mycoplasma pneumoniae
C) Klebsiella pneumoniae
D) Staphylococcus aureus
E) Legionella pneumophila

Question 10:
In the diagnosis of Legionnaires’ disease, which of the following tests is most commonly used?

A) Sputum culture
B) Urinary antigen test
C) Serology
D) Polymerase chain reaction (PCR)
E) Bronchoalveolar lavage culture

Question 11:
A patient with cystic fibrosis presents with increased cough and sputum production. Sputum culture grows Pseudomonas aeruginosa. What is the most appropriate antibiotic regimen?

A) Oral ciprofloxacin
B) Intravenous ceftazidime
C) Inhaled tobramycin
D) Oral azithromycin
E) Intravenous vancomycin

Question 12:
Which of the following is a common cause of atypical pneumonia in the elderly?

A) Streptococcus pneumoniae
B) Haemophilus influenzae
C) Legionella pneumophila
D) Mycoplasma pneumoniae
E) Chlamydophila pneumoniae

Question 13:
A 55-year-old male with a history of alcoholism presents with fever, productive cough, and purulent sputum. Chest X-ray reveals a right lower lobe consolidation with a bulging fissure. What is the most likely causative organism?

A) Klebsiella pneumoniae
B) Streptococcus pneumoniae
C) Staphylococcus aureus
D) Pseudomonas aeruginosa
E) Legionella pneumophila

Question 14:
In the treatment of tuberculosis, which of the following is a common side effect of isoniazid?

A) Ototoxicity
B) Nephrotoxicity
C) Peripheral neuropathy
D) Tendon rupture
E) Photosensitivity

Question 15:
A patient presents with cough, fever, and malaise after cleaning an old warehouse. Chest X-ray shows nodular infiltrates. Which of the following is the most likely diagnosis?

A) Allergic bronchopulmonary aspergillosis
B) Hypersensitivity pneumonitis
C) Tuberculosis
D) Histoplasmosis
E) Sarcoidosis

Question 16:
Which of the following is the first-line treatment for outpatient management of community-acquired pneumonia in adults without comorbidities?

A) Amoxicillin-clavulanate
B) Azithromycin
C) Ceftriaxone
D) Levofloxacin
E) Vancomycin

Question 17:
A 70-year-old male with chronic renal failure presents with fever and cough. A chest X-ray shows a single thin-walled cavity in the left upper lobe. Which of the following organisms is most likely responsible?

A) Staphylococcus aureus
B) Klebsiella pneumoniae
C) Aspergillus fumigatus
D) Mycobacterium tuberculosis
E) Pneumocystis jirovecii

Question 18:
In the diagnosis of pneumocystis pneumonia (PCP), which of the following is the most sensitive diagnostic method?

A) Sputum culture
B) Bronchoalveolar lavage
C) Chest X-ray
D) Serum beta-D-glucan test
E) Sputum PCR

Question 19:
Which of the following is a risk factor for aspiration pneumonia?

A) Smoking
B) Chronic obstructive pulmonary disease
C) Gastroesophageal reflux disease
D) Asthma
E) Allergic rhinitis

Question 20:
A 45-year-old female presents with a fever, cough, and dyspnea. She works in a pet store and has a history of smoking. A chest CT scan shows multiple nodular infiltrates. What is the most likely diagnosis?

A) Bacterial pneumonia
B) Tuberculosis
C) Histoplasmosis
D) Hypersensitivity pneumonitis
E) Sarcoidosis

Question 21:
A 75-year-old male with a history of chronic heart disease presents with high fever, cough, and purulent sputum. Chest X-ray reveals lobar consolidation. Which organism is most likely responsible?

A) Klebsiella pneumoniae
B) Mycoplasma pneumoniae
C) Streptococcus pneumoniae
D) Haemophilus influenzae
E) Staphylococcus aureus

Question 22:
A patient with HIV presents with fever, cough, and weight loss. Chest X-ray shows bilateral interstitial infiltrates. Which of the following is the most likely diagnosis?

A) Pneumocystis jirovecii pneumonia
B) Tuberculosis
C) Cytomegalovirus pneumonia
D) Bacterial pneumonia
E) Kaposi’s sarcoma

Question 23:
A 40-year-old female presents with fever, pleuritic chest pain, and a dry cough following a hiking trip in the Ohio River Valley. Chest CT shows mediastinal lymphadenopathy. What is the most likely diagnosis?

A) Histoplasmosis
B) Coccidioidomycosis
C) Tuberculosis
D) Sarcoidosis
E) Lymphoma

Question 24:
Which of the following is a recommended first-line antibiotic for the treatment of aspiration pneumonia?

A) Amoxicillin
B) Clindamycin
C) Vancomycin
D) Ciprofloxacin
E) Doxycycline

Question 25:
In patients suspected of having pulmonary tuberculosis, what is the significance of a positive interferon-gamma release assay (IGRA)?

A) Confirms active tuberculosis infection
B) Indicates latent tuberculosis infection
C) Determines drug resistance
D) Confirms cured tuberculosis
E) Indicates a false positive tuberculin skin test

Question 26:
A 60-year-old male smoker presents with cough, weight loss, and night sweats. Chest X-ray shows a mass-like lesion in the right upper lobe. What is the most important next step in diagnosis?

A) Sputum culture
B) CT-guided biopsy
C) Bronchoscopy
D) Tuberculin skin test
E) PET scan

Question 27:
A 30-year-old male presents with cough, fever, and dyspnea. He works in a bat-infested cave. Chest X-ray shows diffuse nodular infiltrates. What is the most likely diagnosis?

A) Histoplasmosis
B) Tuberculosis
C) Sarcoidosis
D) Silicosis
E) Hypersensitivity pneumonitis

Question 28:
Which of the following is a typical feature of primary ciliary dyskinesia?

A) Recurrent pneumonias
B) Chronic sinusitis
C) Situs inversus
D) Bronchiectasis
E) All of the above

Question 29:
A patient with a productive cough and hemoptysis has a chest X-ray showing cavitary lesions in the upper lobes. Acid-fast bacilli are seen on sputum smear. What is the most likely diagnosis?

A) Lung abscess
B) Tuberculosis
C) Nocardiosis
D) Bronchiectasis
E) Aspergillosis

Question 30:
Which of the following pathogens is most commonly associated with hospital-acquired pneumonia in mechanically ventilated patients?

A) Streptococcus pneumoniae
B) Haemophilus influenzae
C) Pseudomonas aeruginosa
D) Mycoplasma pneumoniae
E) Staphylococcus aureus

Question 31:
A 25-year-old male with HIV presents with fever, cough, and shortness of breath. His CD4 count is 180 cells/μL. What is the most appropriate prophylactic medication to prevent Pneumocystis jirovecii pneumonia?

A) Azithromycin
B) Isoniazid
C) Trimethoprim-sulfamethoxazole
D) Valganciclovir
E) Fluconazole

Question 32:
Which of the following is a common characteristic of Legionnaires’ disease?

A) Dry cough
B) Lobar consolidation on chest X-ray
C) Hyponatremia
D) Eosinophilia
E) Wheezing

Question 33:
A 50-year-old male presents with cough, fever, and chest pain. He recently returned from a camping trip. Chest X-ray shows a round pneumonia. What is the most likely causative organism?

A) Streptococcus pneumoniae
B) Klebsiella pneumoniae
C) Francisella tularensis
D) Coxiella burnetii

E) Legionella pneumophila

Question 34:
Which antibiotic is most commonly used in the treatment of atypical pneumonia caused by Mycoplasma pneumoniae?

A) Amoxicillin
B) Ceftriaxone
C) Azithromycin
D) Vancomycin
E) Piperacillin-tazobactam

Question 35:
A patient presents with acute respiratory distress and a diffuse bilateral infiltrative process on chest X-ray. Bronchoscopy reveals the presence of hyaline membranes. What is the most likely diagnosis?

A) Acute respiratory distress syndrome (ARDS)
B) Pneumocystis jirovecii pneumonia
C) Pulmonary edema
D) Acute interstitial pneumonia
E) Diffuse alveolar hemorrhage

Question 36:
In children, which of the following organisms is most commonly associated with community-acquired pneumonia?

A) Mycoplasma pneumoniae
B) Streptococcus pneumoniae
C) Staphylococcus aureus
D) Haemophilus influenzae type B
E) Chlamydophila pneumoniae

Question 37:
A 45-year-old female with asthma presents with fever, productive cough, and wheezing. Chest X-ray reveals new infiltrates. Which of the following is the most appropriate initial antibiotic therapy?

A) Amoxicillin
B) Azithromycin
C) Levofloxacin
D) Ceftriaxone
E) Clindamycin

Question 38:
A patient with chronic bronchitis presents with an exacerbation and increased purulent sputum production. Which organism is most likely to be implicated?

A) Pseudomonas aeruginosa
B) Moraxella catarrhalis
C) Staphylococcus aureus
D) Haemophilus influenzae
E) Streptococcus pneumoniae

Question 39:
A patient presents with a chronic cough and weight loss. Chest CT shows nodular infiltrates and a tree-in-bud pattern. What is the most likely diagnosis?

A) Bronchogenic carcinoma
B) Tuberculosis
C) Nontuberculous mycobacterial infection
D) Chronic bronchitis
E) Pulmonary embolism

Question 40:
Which of the following is the preferred initial treatment for mild outpatient pneumonia in a patient allergic to penicillin?

A) Doxycycline
B) Amoxicillin
C) Ceftriaxone
D) Erythromycin
E) Levofloxacin

Question 41:
A 55-year-old female with no significant medical history presents with a fever, dry cough, and progressive dyspnea. Chest X-ray reveals bilateral ground-glass opacities. What is the most likely diagnosis?

A) Bacterial pneumonia
B) COVID-19 pneumonia
C) Pulmonary embolism
D) Heart failure
E) Tuberculosis

Question 42:
A 45-year-old male with a history of intravenous drug use presents with fever and hemoptysis. Chest CT shows multiple cavitary lesions in the lungs. What is the most likely causative pathogen?

A) Staphylococcus aureus
B) Streptococcus pneumoniae
C) Pseudomonas aeruginosa
D) Mycobacterium tuberculosis
E) Mycobacterium avium complex

Question 43:
Which of the following conditions is associated with an increased risk of developing invasive aspergillosis?

A) Diabetes mellitus
B) Chronic obstructive pulmonary disease
C) Neutropenia
D) Gastroesophageal reflux disease
E) Hypertension

Question 44:
A 70-year-old male with chronic renal failure presents with fever, cough, and pleuritic chest pain. Chest X-ray shows consolidation in the right lower lobe. What is the most likely diagnosis?

A) Aspiration pneumonia
B) Pulmonary embolism
C) Lung abscess
D) Acute bronchitis
E) Tuberculosis

Question 45:
Which of the following is the most common radiographic finding in patients with early-stage primary pulmonary tuberculosis?

A) Bilateral apical infiltrates
B) Miliary pattern
C) Hilar lymphadenopathy
D) Cavitary lesions
E) Pleural effusion

Question 46:
A 35-year-old female presents with fever, cough, and headache after returning from a trip to New Mexico. Chest X-ray shows a single pulmonary nodule with a surrounding halo. What is the most likely diagnosis?

A) Coccidioidomycosis
B) Histoplasmosis
C) Tuberculosis
D) Lung cancer
E) Sarcoidosis

Question 47:
Which of the following is the first-line treatment for outpatient management of community-acquired pneumonia in an adult with comorbidities like diabetes and chronic lung disease?

A) Amoxicillin
B) Azithromycin
C) Levofloxacin
D) Ceftriaxone
E) Clindamycin

Question 48:
A patient presents with a fever and a productive cough. Sputum culture grows Legionella pneumophila. Which of the following is the most appropriate antibiotic treatment?

A) Amoxicillin
B) Azithromycin
C) Ceftriaxone
D) Vancomycin
E) Metronidazole

Question 49:
In a patient with suspected ventilator-associated pneumonia, which organism is most commonly responsible?

A) Escherichia coli
B) Streptococcus pneumoniae
C) Pseudomonas aeruginosa
D) Mycoplasma pneumoniae
E) Haemophilus influenzae

Question 50:
A 30-year-old male presents with fever, night sweats, and weight loss. His chest X-ray shows hilar lymphadenopathy and a Ghon complex. What is the most likely diagnosis?

A) Sarcoidosis
B) Lymphoma
C) Primary pulmonary tuberculosis
D) Silicosis
E) Hodgkin’s disease

Question 51:
Which of the following is a typical feature of nontuberculous mycobacterial lung infection?

A) Rapid onset of symptoms
B) Cavitary lesions in the upper lobes
C) Predominantly lower lobe involvement
D) Eosinophilia
E) High fever and chills

Question 52:
A 60-year-old male presents with chronic cough and sputum production. His chest CT reveals bronchiectasis. Which pathogen is commonly associated with this condition?

A) Haemophilus influenzae
B) Pseudomonas aeruginosa
C) Staphylococcus aureus
D) Streptococcus pneumoniae
E) Mycobacterium avium complex

Question 53:
A patient with a history of smoking and COPD presents with an acute exacerbation and purulent sputum. Which antibiotic would be most appropriate for empirical treatment?

A) Doxycycline
B) Azithromycin
C) Amoxicillin
D) Levofloxacin
E) Penicillin

Question 54:
Which of the following clinical features is most suggestive of a viral rather than bacterial cause of pneumonia?

A) High fever
B) Productive cough
C) Rapid onset of symptoms
D) Myalgias and headache
E) Pleuritic chest pain

Question 55:
A patient with a history of asthma presents with wheezing and cough. He recently had a viral upper respiratory infection. Which type of pneumonia is he most at risk for?

A) Aspiration pneumonia
B) Viral pneumonia
C) Bacterial pneumonia
D) Fungal pneumonia
E) Mycoplasma pneumonia

Question 56:
In the diagnosis of pneumocystis pneumonia (PCP), which of the following findings is typically seen on chest X-ray?

A) Lobar consolidation
B) Cavitary lesions
C) Bilateral interstitial infiltrates
D) Pleural effusion
E) Apical nodules

Question 57:
A 25-year-old female presents with a dry cough, fever, and erythema nodosum. Chest X-ray reveals bilateral hilar lymphadenopathy. What is the most likely diagnosis?

A) Sarcoidosis
B) Tuberculosis
C) Lymphoma
D) Bacterial pneumonia
E) Histoplasmosis

Question 58:
Which of the following is the most common cause of hospital-acquired pneumonia in a post-surgical patient?

A) Pseudomonas aeruginosa
B) Staphylococcus aureus
C) Klebsiella pneumoniae
D) Escherichia coli
E) Acinetobacter baumannii

Question 59:
A patient with HIV and a CD4 count of 250 cells/μL presents with cough and shortness of breath. Chest CT shows tree-in-bud opacities. Which organism is most likely responsible?

A) Pneumocystis jirovecii
B) Mycobacterium tuberculosis
C) Mycobacterium avium complex
D) Streptococcus pneumoniae
E) Histoplasma capsulatum

Question 60:
A 40-year-old female presents with fever, cough, and dyspnea. She recently visited a farm. Chest X-ray shows diffuse reticular opacities. Which of the following organisms should be considered?

A) Legionella pneumophila
B) Coxiella burnetii
C) Histoplasma capsulatum
D) Chlamydia psittaci
E) Francisella tularensis

Answers and explanations

Question 1:
Correct Answer: B) Streptococcus pneumoniae
Explanation: The presentation of productive cough, fever, and lobar consolidation is typical of Streptococcus pneumoniae, the most common cause of bacterial lobar pneumonia.
Teaching Point: Streptococcus pneumoniae is the leading cause of community-acquired pneumonia and typically presents with lobar consolidation on chest X-ray.

Question 2:
Correct Answer: A) Streptococcus pneumoniae
Explanation: Streptococcus pneumoniae is the most common cause of community-acquired pneumonia in adults and is known for causing lobar pneumonia.
Teaching Point: Streptococcus pneumoniae pneumonia can present acutely with cough, fever, and pleuritic chest pain, often with a high fever and productive cough.

Question 3:
Correct Answer: D) Psittacosis
Explanation: The history of bird-watching and the symptoms are suggestive of Psittacosis, caused by Chlamydophila psittaci, commonly transmitted from birds to humans.
Teaching Point: Psittacosis should be suspected in individuals with pneumonia who have a history of exposure to birds. It can present with dry cough, fever, and atypical pneumonia on chest X-ray.

Question 4:
Correct Answer: C) Sputum culture
Explanation: While not the quickest, sputum culture is the most sensitive diagnostic test for tuberculosis, allowing for organism identification and drug susceptibility testing.
Teaching Point: Sputum culture for Mycobacterium tuberculosis is important for confirming the diagnosis and guiding treatment, especially in drug-resistant cases.

Question 5:
Correct Answer: B) Pneumocystis jirovecii
Explanation: In an HIV-infected patient with low CD4 count, presenting with bilateral interstitial infiltrates, Pneumocystis jirovecii pneumonia (PCP) is a likely cause.
Teaching Point: PCP is a common opportunistic infection in HIV/AIDS patients with CD4 counts below 200 cells/μL, presenting with bilateral interstitial pneumonia.

Question 6:
Correct Answer: C) Ghon complex
Explanation: The Ghon complex, consisting of a calcified primary focus in the lung and associated lymph node involvement, is a characteristic feature of primary pulmonary tuberculosis.
Teaching Point: The Ghon complex is often seen in primary TB and may be detected on chest X-ray, especially in children or immunocompromised adults.

Question 7:
Correct Answer: B) Tuberculosis
Explanation: The presence of a cavitary lesion in the upper lobe in a patient with systemic symptoms such as night sweats is highly suggestive of tuberculosis.
Teaching Point: Cavitary lesions in the upper lobes, particularly in the context of systemic symptoms like weight loss and night sweats, should raise suspicion for tuberculosis.

Question 8:
Correct Answer: D) Piperacillin-tazobactam
Explanation: Piperacillin-tazobactam is a broad-spectrum antibiotic commonly used as initial empirical therapy for hospital-acquired pneumonia, covering a wide range of bacteria including Pseudomonas aeruginosa.
Teaching Point: Empirical antibiotic therapy for hospital-acquired pneumonia should cover both Gram-positive and Gram-negative organisms, including Pseudomonas.

Question 9:
Correct Answer: B) Mycoplasma pneumoniae
Explanation: Mycoplasma pneumoniae is a common cause of atypical pneumonia in young adults, often presenting with low-grade fever, headache, and a nonproductive cough with patchy infiltrates on chest X-ray.
Teaching Point: Mycoplasma pneumoniae can cause “walking pneumonia,” with a more gradual onset of symptoms compared to typical bacterial pneumonia.

Question 10:
Correct Answer: B) Urinary antigen test
Explanation: The urinary antigen test for Legionella pneumophila is commonly used for rapid diagnosis of Legionnaires’ disease, as it is quick and non-invasive.
Teaching Point: The Legionella urinary antigen test is specific for Legionella pneumophila serogroup 1, the most common cause of Legionnaires’ disease.

Question 11:
Correct Answer: C) Inhaled tobramycin
Explanation: In patients with cystic fibrosis and Pseudomonas aeruginosa infection, inhaled tobramycin is commonly used to reduce bacterial load and improve lung function.
Teaching Point: Chronic Pseudomonas aeruginosa infection in cystic fibrosis can be managed with inhaled antibiotics, reducing exacerbations and preserving lung function.

Question 12:
Correct Answer: C) Legionella pneumophila
Explanation: Legionella pneumophila is a common cause of atypical pneumonia in the elderly, often presenting with symptoms like fever, cough, and hyponatremia.
Teaching Point: Consider Legionella in elderly patients or those with a history of travel or exposure to contaminated water systems presenting with atypical pneumonia.

Question 13:
Correct Answer: A) Klebsiella pneumoniae
Explanation: Klebsiella pneumoniae often presents with a lobar consolidation and a bulging fissure, especially in patients with a history of alcoholism.
Teaching Point: Klebsiella pneumoniae is known for causing severe, rapidly progressive pneumonia with a predilection for the upper lobes and can lead to “currant jelly” sputum.

Question 14:
Correct Answer: C) Peripheral neuropathy
Explanation: Peripheral neuropathy is a common side effect of isoniazid, one of the primary drugs used in tuberculosis treatment.
Teaching Point: Patients on isoniazid should be monitored for signs of peripheral neuropathy, and prophylactic pyridoxine (vitamin B6) supplementation can be given to prevent this side effect.

Question 15:
Correct Answer: B) Hypersensitivity pneumonitis
Explanation: Exposure to organic dusts in an old warehouse can lead to hypersensitivity pneumonitis, presenting with symptoms like cough, fever, and malaise, and nodular infiltrates on chest X-ray.
Teaching Point: Hypersensitivity pneumonitis is an allergic lung disease caused by inhalation of various organic particles. Avoidance of the antigen is key to management.

Question 16:
Correct Answer: B) Azithromycin
Explanation: For outpatient management of community-acquired pneumonia in adults without comorbidities, macrolides such as azithromycin are recommended first-line antibiotics.
Teaching Point: Macrolides are effective against common pathogens causing community-acquired pneumonia and are usually well-tolerated with a low side-effect profile.

Question 17:
Correct Answer: C) Aspergillus fumigatus
Explanation: The presentation of a thin-walled cavity in a patient with chronic renal failure suggests the possibility of aspergillosis, particularly caused by Aspergillus fumigatus.
Teaching Point: Aspergillosis should be considered in immunocompromised patients or those with pre-existing lung cavities presenting with new respiratory symptoms.

Question 18:
Correct Answer: B) Bronchoalveolar lavage
Explanation: Bronchoalveolar lavage is the most sensitive diagnostic method for Pneumocystis jirovecii pneumonia (PCP), particularly in immunocompromised patients.
Teaching Point: BAL allows for collection of respiratory secretions directly from the alveoli, improving the yield of diagnostic tests for organisms like Pneumocystis jirovecii.

Question 19:
Correct Answer: C) Gastroesophageal reflux disease
Explanation: Gastroesophageal reflux disease (GERD) is a risk factor for aspiration pneumonia due to the potential for gastric contents to enter the lungs, especially in individuals with impaired swallowing or esophageal motility.
Teaching Point: Patients with GERD, especially those with neurologic disorders or esophageal dysfunction, should be evaluated for risk of aspiration pneumonia.

Question 20:
Correct Answer: B) Tuberculosis
Explanation: The patient’s history of exposure to a farm environment, smoking history, and the presence of multiple nodular infiltrates on chest CT are suggestive of tuberculosis.
Teaching Point: Tuberculosis should be considered in patients with risk factors such as exposure to high-risk environments or immunosuppression, presenting with nodular or cavitary lung lesions.

Question 21:
Correct Answer: B) COVID-19 pneumonia
Explanation: The presentation of bilateral ground-glass opacities in a patient with progressive dyspnea and dry cough is highly suggestive of COVID-19 pneumonia, particularly given the recent pandemic context.
Teaching Point: COVID-19, caused by the SARS-CoV-2 virus, can present with a range of symptoms from mild to severe, with chest imaging often showing bilateral ground-glass opacities.

Question 22:
Correct Answer: A) Pneumocystis jirovecii pneumonia
Explanation: In an HIV-infected patient with a low CD4 count, presenting with bilateral interstitial infiltrates, Pneumocystis jirovecii pneumonia is a common and serious opportunistic infection.
Teaching Point: Prophylaxis against Pneumocystis jirovecii is recommended in HIV patients with CD4 counts below 200 cells/μL to prevent this potentially fatal infection.

Question 23:
Correct Answer: A) Histoplasmosis
Explanation: The patient’s recent travel to the Ohio River Valley and symptoms are indicative of histoplasmosis, a fungal infection caused by inhaling spores of Histoplasma capsulatum, often found in bird or bat droppings.
Teaching Point: Histoplasmosis should be considered in patients with respiratory symptoms and a history of travel to endemic areas, particularly if involved in activities that disturb soil.

Question 24:
Correct Answer: B) Clindamycin
Explanation: Clindamycin is a recommended first-line antibiotic for aspiration pneumonia due to its effectiveness against anaerobes, which are commonly involved in this type of pneumonia.
Teaching Point: Aspiration pneumonia often involves anaerobic bacteria from the oropharynx and requires antibiotics effective against these organisms.

Question 25:
Correct Answer: B) Indicates latent tuberculosis infection
Explanation: A positive interferon-gamma release assay (IGRA) indicates latent tuberculosis infection. It suggests an immune response to Mycobacterium tuberculosis antigens, without distinguishing between latent infection and active disease.
Teaching Point: IGRA tests are used to detect latent TB infection, especially in individuals who have received the BCG vaccine or in whom the tuberculin skin test is less reliable.

Question 26:
Correct Answer: C) Bronchoscopy
Explanation: In a patient with a lung mass and a history of smoking, bronchoscopy is a crucial next step for diagnosis, allowing for direct visualization and biopsy of the lesion to rule out malignancy or tuberculosis.
Teaching Point: Bronchoscopy is a key diagnostic tool in evaluating lung masses or cavitary lesions, particularly when malignancy or infectious etiologies like tuberculosis are suspected.

Question 27:
Correct Answer: A) Histoplasmosis
Explanation: The patient’s occupation in a bat-infested cave and presentation with diffuse nodular infiltrates suggest histoplasmosis, a fungal infection caused by Histoplasma capsulatum found in bat and bird droppings.
Teaching Point: Occupational and recreational exposures are important to consider in the differential diagnosis of pulmonary infections, especially fungal infections like histoplasmosis.

Question 28:
Correct Answer: E) All of the above
Explanation: Primary ciliary dyskinesia is associated with recurrent pneumonias, chronic sinusitis, situs inversus, and bronchiectasis due to impaired mucociliary clearance.
Teaching Point: Primary ciliary dyskinesia is a genetic disorder characterized by abnormal ciliary function, leading to chronic respiratory tract infections and often situs inversus.

Question 29:
Correct Answer: B) Tuberculosis
Explanation: The presence of cavitary lesions in the upper lobes and acid-fast bacilli on sputum smear strongly suggest tuberculosis.
Teaching Point: Tuberculosis should be suspected in patients with cavitary upper lobe lesions and positive acid-fast bacilli on sputum smear, particularly in high-risk populations.

Question 30:
Correct Answer: C) Pseudomonas aeruginosa
Explanation: Pseudomonas aeruginosa is a common cause of hospital-acquired pneumonia, especially in mechanically ventilated patients, due to its resistance to many antibiotics and prevalence in hospital settings.
Teaching Point: Empirical antibiotic treatment for ventilator-associated pneumonia often includes coverage for Pseudomonas aeruginosa, particularly in patients with risk factors for multi-drug resistant organisms.

Question 31:
Correct Answer: C) Trimethoprim-sulfamethoxazole
Explanation: Trimethoprim-sulfamethoxazole is the recommended prophylactic medication for Pneumocystis jirovecii pneumonia in HIV patients with CD4 counts below 200 cells/μL.
Teaching Point: Prophylaxis against opportunistic infections like PCP is crucial in HIV patients with low CD4 counts to prevent life-threatening infections.

Question 32:
Correct Answer: C) Hyponatremia
Explanation: Hyponatremia is a common feature in patients with Legionnaires’ disease, caused by the Legionella pneumophila bacterium, and can help differentiate it from other causes of pneumonia.
Teaching Point: Legionnaires’ disease often presents with multisystem involvement, including hyponatremia and gastrointestinal symptoms, in addition to respiratory symptoms.

Question 33:
Correct Answer: C) Francisella tularensis
Explanation: The history of a camping trip and the presence of a round pneumonia with a halo sign on chest imaging suggest Francisella tularensis, the causative agent of tularemia, which can be acquired from environmental exposures.
Teaching Point: Tularemia is a zoonotic infection that can present with pulmonary involvement, particularly in individuals with outdoor exposures.

Question 34:
Correct Answer: C) Azithromycin
Explanation: Azithromycin is a macrolide antibiotic commonly used to treat atypical pneumonia, including that caused by Mycoplasma pneumoniae.
Teaching Point: Mycoplasma pneumoniae is a common cause of atypical pneumonia, particularly in younger adults, and responds well to macrolide antibiotics like azithromycin.

Question 35:
Correct Answer: A) Acute respiratory distress syndrome (ARDS)
Explanation: The presence of acute respiratory distress and diffuse bilateral infiltrates with hyaline membranes on bronchoscopy is indicative of acute respiratory distress syndrome (ARDS).
Teaching Point: ARDS is a severe form of lung injury characterized by rapid onset of widespread inflammation in the lungs, leading to severe hypoxemia and respiratory failure.

Question 36:
Correct Answer: B) Streptococcus pneumoniae
Explanation: Streptococcus pneumoniae is the most common cause of community-acquired pneumonia in children and presents with symptoms such as fever, cough, and respiratory distress.
Teaching Point: Vaccination against Streptococcus pneumoniae is an important preventive measure in reducing the incidence of pneumonia in children.

Question 37:
Correct Answer: B) Azithromycin
Explanation: Azithromycin is an appropriate initial antibiotic therapy for community-acquired pneumonia in patients with underlying asthma, as it covers typical and atypical pathogens.
Teaching Point: In patients with chronic lung diseases like asthma, broad-spectrum antibiotics such as macrolides are often used to cover a wide range of potential pathogens.

Question 38:
Correct Answer: D) Haemophilus influenzae
Explanation: Haemophilus influenzae is commonly implicated in acute exacerbations of chronic bronchitis, particularly in smokers or patients with COPD.
Teaching Point: Acute exacerbations of chronic bronchitis often require antibiotic treatment, with the choice of antibiotic guided by the likely causative organisms and patient’s risk factors.

Question 39:
Correct Answer: C) Nontuberculous mycobacterial infection
Explanation: The presence of nodular infiltrates and a tree-in-bud pattern on chest CT is suggestive of nontuberculous mycobacterial infection, particularly in patients with underlying lung disease.
Teaching Point: Nontuberculous mycobacterial infections are increasingly recognized in patients with chronic lung diseases and may require prolonged antibiotic therapy.

Question 40:
Correct Answer: A) Doxycycline
Explanation: For patients allergic to penicillin, doxycycline is a good alternative for the treatment of mild outpatient pneumonia, as it is effective against typical and atypical pathogens.
Teaching Point: In penicillin-allergic patients, alternatives such as doxycycline or macrolides are effective options for treating community-acquired pneumonia.

Question 41:
Correct Answer: B) COVID-19 pneumonia
Explanation: The presentation of bilateral ground-glass opacities in a patient with progressive dyspnea and dry cough is highly suggestive of COVID-19 pneumonia, caused by the SARS-CoV-2 virus.
Teaching Point: COVID-19 should be considered in patients with bilateral ground-glass opacities, especially in the context of a pandemic or if there is a history of exposure.

Question 42:
Correct Answer: A) Staphylococcus aureus
Explanation: In a patient with a history of intravenous drug use presenting with cavitary lung lesions, Staphylococcus aureus is a common causative pathogen, often leading to septic pulmonary emboli.
Teaching Point: IV drug use increases the risk of infections like Staphylococcus aureus, which can cause severe pulmonary infections including abscesses and empyema.

Question 43:
Correct Answer: C) Neutropenia
Explanation: Neutropenia, particularly in the context of chemotherapy or hematological malignancies, significantly increases the risk of developing invasive aspergillosis.
Teaching Point: Patients with prolonged neutropenia are at high risk for fungal infections like aspergillosis and require vigilant monitoring and prompt antifungal therapy if infection is suspected.

Question 44:
Correct Answer: A) Aspiration pneumonia
Explanation: In a patient with chronic renal failure presenting with fever, cough, and consolidation in the lower lobe, aspiration pneumonia should be considered, particularly if there is a history of swallowing difficulties or decreased consciousness.
Teaching Point: Aspiration pneumonia is common in patients with risk factors for aspiration, such as neurologic disorders, impaired consciousness, or esophageal dysmotility.

Question 45:
Correct Answer: C) Hilar lymphadenopathy
Explanation: In early-stage primary pulmonary tuberculosis, hilar lymphadenopathy is a common finding, particularly in children or immunocompromised adults.
Teaching Point: Primary pulmonary tuberculosis, especially in the early stages, can present with lymphadenopathy without extensive parenchymal involvement.

Question 46:
Correct Answer: A) Coccidioidomycosis
Explanation: The patient’s history of travel to New Mexico and presentation with a pulmonary nodule with a surrounding halo suggests coccidioidomycosis, a fungal infection caused by Coccidioides species.
Teaching Point: Coccidioidomycosis, also known as Valley fever, should be considered in patients with compatible symptoms and a history of travel to endemic areas in the southwestern United States.

Question 47:
Correct Answer: C) Levofloxacin
Explanation: For patients with comorbidities such as diabetes and chronic lung disease, a respiratory fluoroquinolone like levofloxacin is recommended for community-acquired pneumonia.
Teaching Point: In patients with community-acquired pneumonia and comorbid conditions, broad-spectrum antibiotics covering both typical and atypical pathogens are indicated.

Question 48:
Correct Answer: B) Azithromycin
Explanation: Azithromycin is effective against Legionella pneumophila and is the treatment of choice for Legionnaires’ disease.
Teaching Point: Legionnaires’ disease, caused by Legionella pneumophila, requires antibiotics effective against atypical pathogens, with macrolides like azithromycin being a common choice.

Question 49:
Correct Answer: C) Pseudomonas aeruginosa
Explanation: In ventilator-associated pneumonia, Pseudomonas aeruginosa is a common and serious pathogen, particularly in patients with prolonged mechanical ventilation or antibiotic use.
Teaching Point: Empirical antibiotic therapy for ventilator-associated pneumonia often includes coverage for Pseudomonas aeruginosa, especially in high-risk patients.

Question 50:
Correct Answer: C) Primary pulmonary tuberculosis
Explanation: The presence of a Ghon complex (a calcified primary focus in the lung and associated lymph node) and hilar lymphadenopathy is suggestive of primary pulmonary tuberculosis.
Teaching Point: Primary pulmonary tuberculosis can present with a Ghon complex, often found incidentally on imaging in asymptomatic individuals or those with mild symptoms.

Question 51:
Correct Answer: B) Cavitary lesions in the upper lobes
Explanation: Nontuberculous mycobacterial lung infection often presents with cavitary lesions in the upper lobes, similar to tuberculosis but typically in older or immunocompromised individuals.
Teaching Point: Nontuberculous mycobacterial infections should be considered in patients with chronic pulmonary symptoms and cavitary upper lobe lesions, especially if tuberculosis tests are negative.

Question 52:
Correct Answer: B) Pseudomonas aeruginosa
Explanation: Pseudomonas aeruginosa is commonly associated with bronchiectasis, particularly in patients with a history of recurrent infections or those with cystic fibrosis.
Teaching Point: Chronic infection with Pseudomonas aeruginosa in bronchiectasis can lead to a decline in lung function and should be treated aggressively.

Question 53:
Correct Answer: D) Levofloxacin
Explanation: Levofloxacin, a respiratory fluoroquinolone, is appropriate for empirical treatment of an acute exacerbation of chronic bronchitis, especially in patients with COPD.
Teaching Point: Antibiotic choice for acute exacerbations of chronic bronchitis should cover common respiratory pathogens, including Haemophilus influenzae and Moraxella catarrhalis.

Question 54:
Correct Answer: D) Myalgias and headache
Explanation: Myalgias and headache are more suggestive of a viral cause of pneumonia. These systemic symptoms are less common in bacterial pneumonia.
Teaching Point: Viral pneumonias often present with systemic symptoms like muscle aches and headaches, in addition to respiratory symptoms.

Question 55:
Correct Answer: B) Viral pneumonia
Explanation: Following a viral upper respiratory infection, patients with asthma are at increased risk for viral pneumonia due to the impact of the virus on airway inflammation and immune response.
Teaching Point: Patients with asthma should be monitored closely after viral upper respiratory infections for signs of worsening respiratory status, which may indicate pneumonia.

Question 56:
Correct Answer: C) Bilateral interstitial infiltrates
Explanation: Bilateral interstitial infiltrates on chest X-ray are typical for Pneumocystis jirovecii pneumonia, especially in immunocompromised patients such as those with HIV/AIDS.
Teaching Point: PCP should be suspected in immunocompromised patients presenting with bilateral interstitial infiltrates and respiratory symptoms.

Question 57:
Correct Answer: A) Sarcoidosis
Explanation: The combination of fever, cough, erythema nodosum, and bilateral hilar lymphadenopathy is highly suggestive of sarcoidosis, a multisystem granulomatous disorder.
Teaching Point: Sarcoidosis often presents with bilateral hilar lymphadenopathy and can be associated with skin manifestations like erythema nodosum.

Question 58:
Correct Answer: C) Klebsiella pneumoniae
Explanation: In a post-surgical patient, Klebsiella pneumoniae is a common cause of hospital-acquired pneumonia, often associated with severe illness and resistance to multiple antibiotics.
Teaching Point: Hospital-acquired pneumonia in post-surgical patients requires empirical antibiotic therapy with coverage for Gram-negative organisms like Klebsiella.

Question 59:
Correct Answer: C) Mycobacterium avium complex
Explanation: In an HIV-positive patient with a CD4 count below 200 cells/μL presenting with respiratory symptoms and tree-in-bud opacities, Mycobacterium avium complex (MAC) is a likely pathogen.
Teaching Point: MAC is a common opportunistic infection in patients with advanced HIV/AIDS and can present with nonspecific respiratory symptoms and characteristic radiographic findings.

Question 60:
Correct Answer: B) Coxiella burnetii
Explanation: Coxiella burnetii, the causative agent of Q fever, should be considered in a patient with fever, cough, and diffuse reticular opacities who has had exposure to farm animals.
Teaching Point: Q fever is a zoonotic disease that can present with pneumonia, often in individuals with exposure to farm animals or animal products.