Infection, ARDS & AIDS Flashcards
- A 25-year-old man with a history of asthma presents with flu-like symptoms. He has peripheral blood eosinophilia and elevated serum IgE. Chest radiograph shows hyperinflation, lobar consolidation and 1-2cm ring shadows around the hilum and upper lobes. The peripheral bronchi are normal. Which of the following is the most likely diagnosis?
A. Noninvasive aspergillosis
B. Tuberculosis
C. Invasive aspergillosis
D. Hypersensitivity pneumonitis
E. Allergic bronchopulmonary aspergillosis (ABPA)
E. Allergic bronchopulmonary aspergillosis (ABPA)
In an asthmatic patient, ABPA is strongly suggested by the presence of randomly distributed, central, moderate to severe bronchiectasis predominantly involving the upper lungs, bronchial wall thickening and centrilobular nodules.
- Which is the most common cause for tree-in-bud appearance on chest CT?
A. Tumour emboli
B. Infection
C. Connective tissue disease
D. Aspiration pneumonitis
E. ABPA
- B. Infection
Bacterial causes include mycobacterium tuberculosis, mycobacterium avium intracellulare complex, staph aureus. Viral causes include Cytomegalovirus (CMV) and respiratory syncytial virus. Fungal causes include invasive aspergillosis.
- A 78-year-old male smoker with hospital admission 2 months ago for a dense left Middle Cerebral Artery (MCA) cerebral infarct presents. He has a 3 week history of low grade fevers and weight loss. Chest radiograph reveals new left lower lobe consolidation with areas of cavitation and air fluid levels, but no hilar lymphadenopathy. Which is the most likely diagnosis?
A. Hospital acquired pneumonia with lung abscess
B. Bronchogenic carcinoma
C. Bronchoalveolar cell carcinoma
D. Aspiration with anaerobic pneumonia
E. Traumatic contusion with lung cysts
- D. Aspiration with anaerobic pneumonia
The superior segments of the lower lobes and posterior segments of the upper lobes are most commonly affected in aspiration pneumonia. Thick walled cavitation, frequently with air-fluid levels, can develop within weeks, mimicking post-primary TB.
- Which of the following features most favours melioidosis rather than tuberculosis?
A. Lobar consolidation
B. Cavitation
C. Lack of pleural involvement
D. Upper lobe predominance of nodular change
E. Rapid progression of clinical features
- C. Lack of pleural involvement
There is significant overlap between the features of melioidosis, pneumonia and TB. However, in melioidosis, simultaneous involvement of other organs is common. Pleural involvement such as effusion, empyema, mediastinal or hilar adenopathy are rare, making them useful differentiating features from TB
- Which of the following most suggests active disease in an adult male with TB?
A. Mediastinal lymph nodes more than 1cm in short axis diameter
B. Right-sided paratracheal lymphadenopathy
C. A Ghon focus
D. Enlarged lymph nodes with low attenuation centres
E. Ranke complex
D. Enlarged lymph nodes with low attenuation centres
Enlarged nodes greater than 2cm often have low attenuation centres on CT due to necrotic change, and are highly suggestive of active disease.
- Which of the following most strongly indicates post-primary rather than primary TB?
A. Consolidation in the mid zones
B. Self-limiting course
C. The absence of lymphadenopathy
D. Pleural effusion
E. Atelectasis
C. The absence of lymphadenopathy
Although there may be overlap of features of primary and post-primary TB, the distinguishing features of postprimary TB include predilection for the upper lobes, the absence of lymphadenopathy and cavitation.
- Which of the following is the most common feature of Pneumocystis jiroveci infection on the CT of a 50-year-old man, 4 months post-bone marrow transplant?
A. Pneumatoceles
B. Diffuse bilateral ground-glass opacification
C. Focal areas of consolidation
D. Pleural effusions
E. Mediastinal lymphadenopathy
B. Diffuse bilateral ground-glass opacification
There are often diffuse bilateral ground-glass opacities and less often, focal areas of consolidation, pleural effusions, and mediastinal lymphadenopathy. Approximately 1⁄3 of patients develop pneumatocoeles, usually in the upper lobes, which usually resolve spontaneously, although infrequently can cause a pneumothorax.
- On reviewing a chest radiograph of a 26-year-old male, multiple small pulmonary nodules and a right-sided pneumothoraxare identified. Which is the most likely diagnosis?
A. Wegener’s granulomatosis
B. Septic emboli
C. TB
D. Alveolar cell carcinoma
E. Histiocytosis
E. Histiocytosis
Osteosarcoma, Wilms’ tumour and histiocytosis are causes of pulmonary nodules with pneumothorax.
@#e 2) In acute respiratory distress syndrome what is the first change usually seen on the chest radiograph?
a. confluent consolidation
b. pleural effusions
c. increased heart size with globular shape
d. volume loss with atelectasis
e. patchy ill-defined opacities
e. patchy ill-defined opacities
Acute respiratory distress syndrome (ARDS) commences with interstitial edema, progressing to congestion and extensive alveolar, and interstitial edema and hemorrhage. The chest radiograph is often normal for the first 24 hours, before patchy opacities appear in both lungs. These progress to massive airspace consolidation over the following 2448 hours. True volume loss, atelectasis, cardiomegaly and effusions are not seen in ARDS.
7) A 43-year-old man with a previous history of polytrauma requiring a long period in intensive care for acute respiratory distress syndrome presents with shortness of breath. An abnormal chest radiograph prompts a highresolution CT scan. What are the most likely findings?
a. bronchiectasis in the lower lobes
b. pleural effusions
c. fibrosis with volume loss in the upper lobes
d. reticular changes in the anterior aspects of the lungs
e. reticular changes in the posterior aspects of the lungs
d. reticular changes in the anterior aspects of the lungs
In most patients who survive acute respiratory distress syndrome (ARDS), there is no functional deficit. Where investigated, however, the most common abnormality detected is a reticular pattern in the ventral non-dependent lung. The extent of this is negatively related to the extent of opacification in the acute phase and strongly related to the duration of mechanical ventilation. Bronchiectasis is seen in both acute and chronic phases but is less common than reticular change. Upper-lobe fibrosis is not associated with ARDS.
12) An 87-year-old male presents with fever and cough. A chest radiograph shows dense consolidation in the right mid-zone, which is seen to be in the apical segment of the lower lobe on a lateral view. The oblique fissure is seen to be bulging away from the consolidation. There is an associated effusion. What is the most likely diagnosis?
a. Haemophilus influenzae pneumonia
b. Staphylococcus aureus pneumonia
c. Streptococcus pneumoniae pneumonia
d. Klebsiella pneumonia
e. Legionnaires’ disease
d. Klebsiella pneumonia
Klebsiella pneumonia is typically seen in elderly, debilitated men and produces dense, lobar consolidation, with bulging of the fissure sometimes seen. This may also be seen with pneumococcal pneumonia, but less commonly. Klebsiella may also cause empyema (the commonest cause) and patchy bronchopneumonia. Cavitation occurs in 50%. Staphylococcus aureus pneumonia has a bronchopneumonia pattern which may coalesce, and cavitation is common. Multiple abscesses tend to occur in intravenous drug addicts. Effusions and empyema are common. Streptococcal pneumonia occurs in all ages, especially young adults, and often produces a lobar consolidation in the basal region. Haemophilus influenzae pneumonia has no characteristic appearance. Legionnaires’ disease causes a spreading consolidation of bronchopneumonia type.
43) A 35 year old with asthma presents with malaise, flu-like illness and cough. Previous similar episodes have occurred. A chest radiograph shows patchy airspace opacification in the mid and upper zones. Which feature on highresolution CT would make allergic bronchopulmonary aspergillosis a more likely diagnosis than extrinsic allergic alveolitis?
a. widespread centrilobular micronodules ,3 mm
b. tubular finger-like opacities
c. bronchiectasis
d. upper-zone fibrosis
e. pleural effusion
b. tubular finger-like opacities
Allergic bronchopulmonary aspergillosis (ABPA) is hypersensitivity to aspergillus in people with asthma. Typical features are of a migratory pneumonitis, predominantly in the upper lobes. It may cause bronchiectasis and upper-zone fibrosis, which are features also seen in extrinsic allergic alveolitis (EAA). Tubular opacities, indicating mucus plugging, are seen in ABPA, but not in EAA. Centrilobular nodules are seen in EAA, along with mosaic perfusion and patchy ground-glass change. Pleural effusions are rarely seen in EAA and not in ABPA.
3) Which of the following would be most in keeping with the appearance of pulmonary hydatid disease?
a. multiple subcentimetre nodules throughout both lungs with no cavitation
b. unilateral patchy alveolar changes with unilateral hilar lymphadenopathy
c. solitary ovoid mass with air–fluid level and floating debris
d. bilateral basal reticular change
e. 3 cm, rounded mass with central calcification
c. solitary ovoid mass with air–fluid level and floating debris
The lungs are the second most frequent site affected by hydatid disease in adults, being involved in up to 25% of cases. Commonly, a solitary ovoid or spherical mass is seen in the lower lobes. These can be quite large, measuring up to 20cm in size. There is communication with the bronchial tree, producing air–fluid levels, and the wall of the cyst may be visible, and may appear as a curvilinear opacity or floating debris. Calcification may occur within the wall of the cyst in a few cases.
@# 41- Which of the following CT features indicates post-primary rather than primary pulmonary tuberculosis?
(a) Miliary nodules
(b) Bronchiectasis
(c) Cavitation
(d) Tree-in—bud opacification
(e) Lymphadenopathy
(a) Miliary nodules
The difference between primary and post—primary (reactivated) TB is in the degree Of previous exposure the patient has had to T B. Most features are seen in both to some degree with the exception of miliary nodules.
43- With respect to Mycoplasma pneumoniae infection, which of the statements is not true?
(a) It is the commonest non—bacterial cause of pneumonia
(b) It usually affects previously healthy individuals
(c) It usually affects the upper lobes
(d) Cavitation is not a feature
(e) Radiographic resolution may take up to 2 months
(c) It usually affects the upper lobes
Mycoplasma pneumoniae infection has a predilection for the lower lobes, although isolated upper lobe infection is well recognized. A nodular interstitial pattern may also be seen, the frequency of this finding varies significantly between series, as does the prevalence of pleural effusion.
48- The ITU team to discuss a chest radiograph on. one of their patients- Which of the following features suggest ARDS over- cardiogenic pulmonary edema?
(a) Ratio of arterial oxygenation to inspired oxygen fraction 300
(b) Bilateral pulmonary infiltrates
(c) Pulmonary arterial wedge pressure 20 mmHg
(d) Heart size 15 cm
(e) Bilateral pleural effusions
(d) Heart size 15 cm
ARDS is a response of the lung to injury which may be direct or indirect; radiological features are those of noncardiogenic edema which develops as a consequence but unlike simple edema an interstitial fibrosis may develop. Mechanical ventilation is thought to contribute to this process. Pulmonary arterial wedge pressure 18 mmHg suggests raised left atrial pressures. The diagnosis of ARDS requires the ratio of arterial oxygenation to inspired oxygen to be < 200 mmHg.
1 A 36 year old man has returned from a long adventure holiday in South-Eastern USA. He had an episode of fever, dry cough and polyarthralgia. He still has dyspnoea and on examination is noted to have erythema nodosum on his shins. CXR shows diffuse bilateral tiny calcific nodules, some with central calcification, and hilar and mediastinal ‘popcorn’ calcified lymphadenopathy. What is the most likely diagnosis?
(a) Acute sarcoidosis
(b) Histoplasmosis
(c) Langerhans Cell Histiocytosis
(d) TB
(e) Varicella pneumonia
(b) Histoplasmosis
Histoplasmosis is endemic in certain areas of the USA, particularly Ohio, Mississippi, and the St Lawrence river valley. Acute infection produces flu-like symptoms (polyarthralgia, fever). Acute CXR findings may be non-specific, but include diffuse subsegmental opacities, +/lymphadenopathy. Sub-acute infection results in small calcific nodules and there may be hilar or mediastinal LNs which can display popcorn calcification. The ‘target lesion’ with central calcification is said to be pathognomonic.
24 A patient undergoing induction chemotherapy for the treatment of acute myeloid leukaemia undergoes a chest CT. This shows several foci of consolidation with a halo of ground glass opacification. What is the most likely diagnosis?
(a) Leukaemic infiltrate
(b) Mycobacterium avium infection
(c) Klebsiella spp. infection
(d) Pulmonary thromboembolic disease
(e) Angioinvasive aspergillosis
(e) Angioinvasive aspergillosis
This group of patients are severely immuno-suppressed and are particularly prone to fungal chest infections, which need to be recognised early and treated aggressively.
33 An 18 year old woman with proven hydatid disease of the liver presents with chest pain and fever. She has a CXR which shows an 8 cm cystic lesion in the right lung. Which of the following features would be least expected in lung echinococcosis?
(a) Calcification of the cyst wall
(b) Water lily sign
(c) An air/fluid level within cyst
(d) Ground glass change around the cyst
(e) The size of the lesion
(d) Ground glass change around the cyst
Lung involvement occurs in 15-25% of hydatid cases with a lower lobe preponderance. The cystic lesion is solitary in up to 75% of cases. It has a sharply defined ovoid/ spherical appearance and can measure up to 20 cm. It is characterised by varying degrees of collapse of the endocystic membrane leading to the so called ‘water lily’, ‘serpent’ and ‘cumbo’ signs. Rib and vertebral erosion is rarely seen.
57 What is the most common thoracic complication of HIV worldwide?
(a) Bacterial pneumonia
(b) Kaposi’s sarcoma
(c) Pneumocystis infection
(d) Lymphoma
(e) Tuberculosis
(e) Tuberculosis
Tuberculosis co-infection is the commonest complication worldwide. In the UK, bacterial infection is commonest, with unusual organisms seen more commonly than in the general population.
- A 35 year old woman presents with chest infection and pyrexia and the plain film reveals dense lobar consolidation with bulging fissures. The likely micro-organism is:
a. Legionella pneumophila
b. Pneumocystis carinii
c. Staphylococcus
d. Streptococcus
e. Klebsiella
e. Klebsiella
Klebsiella Klebsiella causes a dense pneumonia with bulging of fissures often associated with an empyema. Pneumococcal pneumonitis can also mimic this
@#1 6. A 35 year old man undergoes autologous bone marrow transplantation following successful treatment of lymphoma. Two weeks later he develops scattered bilateral progressive breathlessness and dry cough. HRCT demonstrates several areas of bilateral ground glass changes with associated reticular changes, but no effusions. What is the most likely explanation?
a. Angioinvasive aspergillosis
b. Lymphoid interstitial pneumonia
c. CMV pneumonia
d. Drug toxicity
e. Pulmonary oedema
d. Drug toxicity
Drug toxicity Post transplant pulmonary complications may develop in up to 40–60% of patients.
In the first two weeks or so after transplantation, neutropaenia is the underlying cause for most of these.
Angioinvasive aspergillosis presents in the first two to three weeks, usually as multiple ground glass nodules with or without cavitation and peribronchiolar consolidation.
Lymphoid interstitial pneumonia (LIP) is a late-phase complication usually seen more than three months after transplantation and may be an indication of chronic graft-versus-host response.
CMV pneumonia may manifest at any time in the first 100 days after transplantation. Multiple nodules with associated ground glass changes or consolidation are usually seen, but reticular change is not a feature.
Pulmonary oedema is also seen in the neutropaenic phase in the first two to three weeks. Whilst ground glass changes and interstitial lines are seen in pulmonary oedema, associated pleural effusion is common.
Drug toxicity due to a variety of chemotherapeutic agents is seen in the neutropaenic phase as a combination of ground glass and reticular changes…
@#e 12. A 22 year old is diagnosed with tuberculosis. Which of the following features will make a diagnosis of primary tuberculosis more likely?
a. Mediastinal enlargement
b. Septal thickening
c. Upper zone cavitation
d. Miliary nodules
e. Apical consolidation
a. Mediastinal enlargement
Mediastinal enlargement Mediastinal lymph node enlargement is a feature of primary TB. The others are seen with reactivation or fibrocavitary TB. Miliary TB can be seen in any phase with haematogenous dissemination but primary presentation is uncommon.
- A 22 year old asthmatic presents with recurrent wheeze and productive cough with expectoration of brown sputum. Plain chest radiograph demonstrates multiple pulmonary infiltrates. Which of the following appearances on HRCT would be the most appropriate for acute allergic bronchopulmonary aspergillosis?
a. Finger-in-glove opacity
b. Thick-walled cavity
c. Pleural thickening with or without an effusion
d. Endobronchial mass with distal atelectasis
e. Tree-in-bud appearance
a. Finger-in-glove opacity
Finger-in-glove opacity Acute allergic bronchopulmonary aspergillosis is seen as homogeneous, tubular, finger-inglove areas of increased opacity in a bronchial distribution, usually involving the upper lobes. These shadows are related to plugging of airways by hyphal masses with distal mucoid impaction and can migrate from one region to another on HRCT. Thickwalled cavities and pleural thickening are features of saprophytic aspergillosis. Endobronchial lesion with distal atelectasis is seen mainly in chronic necrotising aspergillosis, whilst tree-in-bud appearance is seen with bronchiolitis in airway invasive aspergillosis.
@# 32. A 35 year old female presents with generalised malaise and cough, occasionally bringing up grape-skin-like material. Blood screen reveals eosinophilia. The patient has a history of travel to several countries worldwide. Which of the following plain film features is unlikely?
a. Homogenous ovoid opacity
b. Cyst with a fluid level
c. Bilateral opacities
d. Calcification.
e. Lower zone location
d. Calcification.
Calcification The case describes hydatid disease. Hydatid cyst of the lungs can present as solid ovoid solitary or occasionally multiple lesions on plain films. When the cyst communicates with a bronchial tree, an air fluid level is demonstrated. Several other signs are described. Whilst bilaterality is less likely (up to 20%), calcification is extremely rare (0.7%).
- A 33 year old male patient suffering from AIDS presents with constitutional symptoms and dry cough. His CD4 count is 150. HRCT is least likely to show:
a. Pleural effusion
b. Ground glass changes
c. Bilateral interstitial infiltrates
d. Diffuse alveolar infiltrates
e. Pneumatocoeles
a. Pleural effusion
Pleural effusion Pneumocystis carinii is the most common cause of pneumonia at this stage of the disease. Pleural effusions and lymphadenopathy are not features of PCP.
A 25-year-old asthmatic man is referred to the chest outpatient clinic with a fever, cough and shortness of breath. A course of antibiotics has not improved his symptoms. Investigations performed in the clinic include a positive skin test for Aspergillus jumigatus and an elevated serum IgE. The patient is known to be immunocompetent with no previous history of sarcoidosis or tuberculosis. Which one of the following are the most likely high-resolution CT (HRCT) findings?
A A lower lobe predominance
B An air crescent sign
C Central bronchiectasis
D The halo sign
E Wedge-shaped peripheral infarcts
C Central bronchiectasis
Allergic bronchopulmonary aspergillosis (ABPA) is part of a spectrum of disease caused by Aspergillus fumigatus. Hypersensitive individuals (commonly those with asthma) can present with ABPA and the key radiological features are central airway mucoid impaction leading to central bronchiectasis.