Histopathology: Lung Pathology Flashcards
Infant presenting with respiratory failure. Bowel loops and the liver can pass into the thorax and compress the developing lung, causing hypoplasia of the lung. What is this condition?
Congenital diaphragmatic hernia
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Respiratory tract infection
A lung mass composed of terminal bronchioles. There are no normal alveoli. What is this condition?
Congenital (Cystic) Adenomatoid Malformation
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A discrete mass of lung tissue that has no normal connection with the respiratory tract. What is this condition?
Pulmonary sequestration
Arterial pO2 <8kPa. What is this condition?
Respiratory Failure
Presents as shortness of breath. Caused by severe pneumonia, pulmonary embolism, acute asthma, pulmonary fibrosis. Caused by ventilation/perfusion mismatching (Increased ventilation removes excess CO2). What is this condition?
Type 1 respiratory failure
Caused by COPD, neuromuscular disorders impairing ventilation. Generalized alveolar hypoventilation (Both O2 and CO2 transfer Impaired). What is this condition?
Type 2 respiratory failure
A very severe form of acute lung injury defined as a ratio of PaO2:FiO2 <200mmHg in the presence of bilateral alveolar infiltrates on chest X-ray and in the absence of left ventricular failure. What condition is this?
Acute respiratory distress syndrome
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PaO2/FiO2 ratio is the ratio of arterial oxygen partial pressure to fractional inspired oxygen
Histopathology: diffuse alveolar damage characterized by the presence of hyaline membranes lining alveolar spaces. Hyaline membranes are composed of a mixture of fibrin and necrotic alveolar epithelial cells. Most likley diagnosis?
Acute respiratory distress syndrome
Persistent productive cough and haemoptysis. Histopathology: Bronchial dilation with marked chronic inflammation in the wall, often with lymphoid aggregates and germinal centres. Adjacent alveoli may show an acute and organizing pneumonia. Most likely diagnosis?
Bronchiectasis
An abnormal permanent dilation of bronchi accompanied by inflammation in their walls and in adjacent lung parenchyma. What is this condition?
Bronchiectasis
An inherited disorder caused by a mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Lack of normal CFTR causes a defective electrolyte transfer across epithelial cell membranes, resulting in thick mucus secretions.
What is this condition?
Cystic Fibrosis
Most patients present with pulmonary disease due to recurrent infections. Initially, common bacteria colonize the lungs, but eventually Pseudomonas aeruginosa often becomes the dominant organism. Pancreatic insufficiency is also common. Bowel obstruction may occur in the neonatal period due to thick meconium (meconium ileus) or develop later in childhood. Liver disease develops late. Some cases may be diagnosed when a raised serum immunoreactive trypsin is picked up on neonatal screening. What is this condition?
Cystic Fibrosis
Shortness of Breath, sudden onset. Histopath: Leisions composed of a mixture of fibrin and enmeshed blood cells, often arranged in alternating linear bands that correspond to the macroscopic lines of Zahn. What is this condition?
Pulmonary embolism
A mean pulmonary artery pressure >25mmHg at rest or >30mmHg during exercise. What is this condition?
Pulmonary Hypertension
Presents with exertional dyspnoea and fatigue. Dizziness and syncope are also common. May be idiopathic or associated with certain drugs, HIV infection, collagen vascular disease, and congenital systemic-to-pulmonary shunts. What is this condition?
Pulmonary Hypertension
Histopatholoy: All cases show muscular hypertrophy and intimal proliferation of small pulmonary arteries and muscularization of pulmonary arterioles.
- Severe cases show plexiform lesions, characterized by a proliferation of slit-like vascular spaces from the arterial wall.
- Very severe cases may display fibrinoid necrosis of the arterial wall.
Pulmonary hypertension
A chronic inflammatory disorder of large airways characterized by recurrent episodes of reversible airway narrowing. What is this condition?
Asthma
Intermittent episodes of breathlessness, wheeze, and chest tightness. Cough, particularly at night, is also common.
Histopathology: Airways show evidence of inflammatory activity with eosinophils which are not usually seen in normal airways. There may also be basement membrane thickening, goblet cell hyperplasia, and prominent smooth muscle.
Most likely diagnosis?
Asthma
A chronic lung condition characterized by breathlessness due to poorly reversible and progressive airflow obstruction. What is this condition?
Chronic Obstruxtive Pulmonary Disorder
Sudden onset of exertional breathlessness on a background of prolonged cough and sputum production. Spirometry typically shows a low FEV1 and low FEV1/FVC ratio. The lungs are hyperinflated with thick mucus in the airways and dilated terminal airspaces. Bullae may be present. Most likely diagnosis?
COPD
Histopathology: Chronic inflammation and fibrosis of small bronchioles (chronic obstructive bronchiolitis). Finely pigmented macrophages in respiratory bronchioles (respiratory bronchiolitis). Dilated terminal airspaces (emphysema). Larger airways may show mucus gland hyperplasia.
COPD
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- Chronic inflammation and fibrosis of small bronchioles (chronic obstructive bronchiolitis).
- Finely pigmented macrophages in respiratory bronchioles (respiratory bronchiolitis).
- Dilated terminal airspaces (emphysema).
Four main patterns of pneumonia. What are they?
Bronchopneumonia
Lobar pneumonia
Abscess formation
Granulomatous inflammation
Elderly, presentation of breathlessness. Sputum reveals Staphylococcus aureus (Or another low-virulence organism). CXR: diffuse shadowing. Most likely diagnosis?
Bronchpneumonia
Lung pathology: patchy bronchial and peribronchial distribution in lower lobes. Most likely diagnosis?
Bronchopneumonia
Acute bacterial infection of large portion of a lobe or entire lobe. What is this condition?
Lobar pneumonia
Phases of histology:
- Congestion
- Red hepatization
- grey hepatization
- Resolution
What is this condition?
Lobar pneumonia
Lung histology shows hyperaemia and intra-alveolar fluid. Most likely diagnosis?
Lobar pneumonia, congestion phase
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NB four phases of lobar pneumonia
Interstitial inflammation without accumilation of intra-alveolar inflammatory cells. Chronic inflammatory cells within alveolar septa with oedema. Most likely diagnosis?
Atypical pneumonia(s)
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Interstitial inflammation = Pneuomonitits
Lung infection caused by mycoplasma, viruses, coxiella, chlamydia. What is this condition?
Atypical pneumonia
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Viruses include CMV and influenza
Abnormally thick mucus secretion from birth. What is this condition?
Cystic fibrosis
Genetic abnormality leads to defective ion transport and therefore excessive reabsorption of water from secretions of exocrine glands. What is this condition?
Cystic fibrosis
Accumilation of fluid in alveolar spaces as a consequence of leaky capllaries or back pressure from a failing left ventricle. What is this condition here?
Pulmonary oedema
Heavy watery lungs on examination, intra-alveolar fluid on histology. What is this condition?
Pulmonary oedema
Chest Xray shows white out of fluffy infiltrates in all lung fields. What is this condition?
diffuse alveolar damage (Acute Respiratory Distress Syndrome in adults)
What causes ARDS?
- DIC
- Pancreatitis
- Shock
- Blood transfusion
- Infection
- Aspiration
- Trauma
- Inhaled irritant gas
Permanent loss of alveolar parenchyma. What is this condition here?
Emphysema
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ie loss of iconic alveolar shape
1 rare metabolic condition that causes empohysema?
-Alpha-1 anti trypsin deficiency
Cadmium exposure causes what respiratory condition?
Emphysema
Lung histology: collection of histiocytes and/or macrophages.
Granulomatous disease
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Can be necrotising or non-necrotising.
Lung histology shows granuloma. What is the first thing to be ruled out?
TB
Lung histology show’s non-infectious granuloma. What is the most likely cause?
Sarcoidosis
Male, 54 years, accountant. Chronic SOB and cough. Lung biopsy shows interstitial fibrosis at varying stages. Most likely diagnosis?
Fibrosing lung disease/ Idiopathic pulmonary fibrosis
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Progressive condition
Not COPD because of fibrosis?
Acute onset of SOB, cough and fever. CXR shows alveolar infiltrates. Most likely diagnosis?
Fibrosing lung disease/ Extrinsic allergic alveolitis (“farmers lung”)
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- Pneumonia wouldnt be as sudden and CXR would look different.
- Asthma wouldn’t show CXR signs.
Male, 54 years, boiller worker. Chronic SOB and cough. Lung biopsy shows fine subplural basal fibrosis. Most likely diagnosis?
Fibrosing lung disease/ Industrial lung disease (“pneumoconiosis”)
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Essentially asbestosis?
Summarise the causes of pulmonary hypertension
Pre-capillary
- Vasoconstrictive
- Chronic hypoxia
- Embolic
- Thomboembolism
Capillary
-Widespread pulmonary fibrosis
Post-capillary
-Left sided heart failure
Nutmeg liver suggests what?
Hepatic venous congestion which suggests pulmonary hypertension
Chronic haemoptysis, SOB and chest pain. Lung biopsy shows granulomatous inflammation of the pulmonary vessels. Most likely diagnosis?
Pulmonary vasculitits.
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Not TB or other granulomatous disease because the granulomatous inflammation is around the blood vessels, not the bronchioles or rest of lung. Also haemoptysis suggests its not TB or sarcoid.
Summarise the 4 main types of lung tumours
- Non-small cell carcinoma (80%)
- Squamous cell carcinoma (30%)
- Adenocarcinoma (30%)
- Large cell carcinoma (20%)
- Small cell carcinoma (20%)
Male, 54 years, accountant. Progressive breathelessness, a chronic dry cough and weight loss. Lung biopsy shows an invasive proliferation of epithelial cells showing keratinization and intercellular bridges. Most likely diagnosis?
Squamous cell carcinoma
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Male, 54 years, accountant. Chronic SOB and cough. Lung biopsy with immunohistological stain shows p63+, CK5+, CK7-, TTF1- . Most likely diagnosis?
Squamous cell carcinoma
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Lung tumour immunohistochemistry:
Squamous cell: p63+, CK5+, CK7-, TTF1-
Adenocarcinoma: CK7+, TTF1+, p63-, CK5-
Small cell: CD56+, CK7+, TTF1+, p63-, CK5-
Male, 54 years, accountant. Progressive breathelessness, a chronic dry cough and weight loss. Lung biopsy shows an invasive proliferation of epithelial cells showing glandular differentiation and mucin production. Most likely diagnosis?
Adenocarcinoma of the lung
Male, 54 years, accountant. Chronic SOB and cough. Lung biopsy shows mucin production and immunohistological stain shows CK7+, TTF1+, p63-, CK5-. Most likely diagnosis?
Adenocarcinoma of the lung
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Lung tumour immunohistochemistry:
Squamous cell: p63+, CK5+, CK7-, TTF1-
Adenocarcinoma: CK7+, TTF1+, p63-, CK5-
Small cell: CD56+, CK7+, TTF1+, p63-, CK5-
Male, 54 years, accountant. Progressive breathelessness, a chronic dry cough and weight loss. Lung biopsy shows an invasive proliferation of poorly differentiated cells, with scant cytoplasm, finely granular chromatin and absent nucleoli. Some signs of necrosis. Most likely diagnosis?
Small cell carcinoma (lung)
Male, 54 years, accountant. Chronic SOB and cough. Lung biopsy with immunohistological stain shows CD56+, CK7+, TTF1+, p63-, CK5-. Most likely diagnosis?
Small cell carcinoma
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Lung tumour immunohistochemistry:
Squamous cell: p63+, CK5+, CK7-, TTF1-
Adenocarcinoma: CK7+, TTF1+, p63-, CK5-
Small cell: CD56+, CK7+, TTF1+, p63-, CK5-
What is the most significant mutation relating to lung cancer and what therapy targets this?
EFGR mutation
Therapy: Cetuximab (Antibody against EGFR)
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NB immunotherapy (ie monoclonal antibodies) can be used to target specific mutated and oncogenic pathways
