Pathology Resit

• Thrombo - phebitis : Thrombotic disease of veins accompanied by varying degrees of inflammation
• Thrombophlebitis : Association between deep vein thrombosis and presence of cancer in an internal organ (Trousseau syndrome = Migratory Thrombo-phlebitis). The majority of the tumours are mucin-producing Adeno-Carcinomas of the pancreas
• Clinical features of Thrombophlebitis :

  • Minimal or marked oedema of the extremity

  • Purulent Thrombo-Phlebitis: Marked chills and high temperature
• Stasis ulcer is a long term complication of thrombophlebitis
• Thrombangitis Obliterans (Buerger's disease) : Rare thrombotic and inflammatory disease of the arteries and veins of unknown aetiology
• Epidemiology of Buerger's Disease :

  • Common in young men (20-35 years)

  • Exacerbation by heavy cigarette smoking
• To the pathologist, vasculitis generally denotes the presence of primary vascular inflammation, in the absence of infection, infarction, or other secondary cause
• Classification of vasculitis depends on at least three major features:

  1. Size and type of vessel involved
  2. Presence of immune complexes
  3. Association with known autoimmune disease, and systemic or localised distribution
• • Two vasculitic syndromes affect elastic arteries: Takayasu disease and Giant-cell arteritis
  • Two vasculitic syndromes affect muscular arteries in the absence of small vessel involvement: Polyarteritis nodosa and Kawasaki disease
• A host of vasculitis syndromes affect small vessels (arterioles,capillaries, and venules)

  • These vasculitides are generally divided into:

  1. Those that are caused by immune complex deposition
  2. Those that are pauci - immune (often antineutrophil cytoplasmic antibody [ANCA] related)
• Epstein-Barr virus causes Nasopharyngeal Carcinoma (Undifferentiated)
• Sarcoidosis is a multisystem, non-infectious granulomatous disease that produces chronic interstitial fibrosis
• Radiologic findings of Sarcoidosis :

  • Bilateral hilar lymphadenopathy ( butterfly - like appearance )
  • Interstitial lung disease (diffuse reticular densities)
• Laboratory findings of Sarcoidosis:

  • Hypercalcaemia and hypercalciuria
  • Hypergammaglobulinaemia
  • Increased activity of serum Angiotensin-Converting Enzyme
• Sarcoidosis has findings of Schaumann & asteroid bodies
• Pulmonary form of Tbc: Inhalation of droplets with the organism

  Non-pulmonary form of Tbc: Ingestion of infected milk
• Primary Tbc:

  • Initial infection, characterised by the primary or Ghon complex (Peripheral sub-pleural parenchymal lesion + Hilar lymph nodes)
  • Clinical picture: Asymptomatic; No clinically evident disease
  • Histopathology:
  • Tubercle (Granuloma of Tbc):
  • ➢ Central caseous necrosis
  • ➢ Langhans giant cells
• Secondary Tbc:

  • Activation of a prior Ghon complex, with spread to a new pulmonary or extra-pulmonary site
  • Clinical features:
  • ➢ Progressive disability
  • ➢ Fever
  • ➢ Haemoptysis
  • ➢ Bloody pleural effusion
  • ➢ Generalised wasting
• Secondary Tbc:

  • Macroscopic picture:
  • ➢ Localised lesions: Apical or posterior segments of the upper lobes
  • ➢ Involvement of hilar lymph nodes
  • Microscopic picture:
  • ➢ Liquefaction and expulsion of the caseous contents → Formation of cavitary lesions
  • Cavitation: Only in secondary Tbc
  • Caseation: Both primary and secondary Tbc
  • ➢ Scarring and calcification
• Miliary Tbc:

  ➢ Secondary Tbc, complicated by lymphatic and haematogenous spread

  ➢ Involvement of distal organs with innumerable small seed – like lesions

  ➢ Extra-pulmonary Tbc:

  Tuberculous meningitis

  Pott disease of the spine

  Para-vertebral or psoas abscess
• Emphysema : Irreversible enlargement of the airspaces distal to the terminal bronchiole, accompanied by destruction of their walls without obvious fibrosis
• Emphysema is associated with cigarette smoking
• Types of emphysema (according to anatomic distribution within the lobule):

  1. Centri - acinar (95% of cases)
  2. Pan - acinar
  3. Para - septal
  4. Irregular
• Clinical features:

  • “ Pink puffer ” vs. “Blue bloater” (Chronic Bronchitis)
  • ↑ Antero-posterior chest-diameter (“ Barrel ” chest)
  • ↑ Total vital capacity
  • Hypoxia
  • Cyanosis
  • Respiratory acidosis
  • Pursed lip breathing
• Assumed causes of Emphysema:

  • Action of proteolytic enzymes (e.g. elastase) on the alveolar wall
  • Elastase:
  • Induces destruction of elastin
  • Neutralised by the opposing action of alpha1-antitrypsin
  • Cigarette smoking:
  • Attracts neutrophils and macrophages (sources of elastase)
  • Inactivates alpha1-antitrypsin
• Centri - acinar (Centri - lobular) Emphysema

  • Affects central or proximal parts of the acini, formed by respiratory bronchioles
  • Sparing of distal alveoli
  • More common and more severe in the upper lobes, particularly in the apical segments
  • Presence of large amounts of black pigment in the walls of the emphysematous spaces
  • Inflammation around bronchi and bronchioles
  • Association with heavy cigarette smoking and chronic bronchitis
• Pan - acinar (Pan-lobular) Emphysema

  • Characterised by evenly enlarged acini from the level of respiratory bronchiole to the terminal blind alveoli (entire acinus: alveoli, alveolar ducts and respiratory bronchioles)
  • Uniform distribution throughout the entire lung
  • Occurrence mainly in the lower zones and in the anterior margins of the lung; Most severe at the bases
  • Association with a1 - antitrypsin deficiency
• Distal Acinar (Para - septal) Emphysema

  • Dilatation of the distal part of the acinus (alveoli and lesser alveolar ducts)
  • Normal proximal portion of the acinus
  • Localised adjacent to the pleura (along the lobular connective tissue septa), and at the margins of the lobules
  • Occurrence adjacent to areas of fibrosis, scarring, or atelectasis
  • More severe in the upper half of the lungs
  • Multiple, continuous enlarged airspaces (0.5-2.0cm) → Large sub-pleural bullae or blebs → Pneumothorax
• Irregular Emphysema

  • Irregular involvement of the acinus
  • Airspace enlargement with fibrosis
  • Pathogenesis: Inflammatory process → Scarring within the walls of enlarged air spaces → Irregular Emphysema
• Complications of Emphysema:

  • Chronic Bronchitis
  • Interstitial Emphysema : Tear in the airways → “Leakage” of air into the interstitial tissue of the chest
  • Rupture of a surface bleb (apical bulla) → Pneumothorax
• Bullous Emphysema

  • Localised accentuation of emphysema, resulting in the formation of large sub-pleural blebs or bullae (>1cm; distended state)
  • Occurrence, possible in any type of emphysema
  • Sometimes, in relation to old tuberculous scarring
• Interstitial Emphysema

  • Entrance of air into the connective tissue stroma of the lung, mediastinum, or subcutaneous tissue
  • Cause/Pathology: Coughing + bronchiolar obstruction → Sharply increased pressures within the alveolar sacs → Alveolar tears → Entrance of air into the lung’s stroma
  • Other Causes:
  • Wound of the chest → Entrance of air within the lung substance
  • Fractured rib → Puncture of the lung parenchyma → Entrance of air within the lung substance
• Papilloma is a benign tumour
• Papilloma is localised in the large bronchi
• Multiple papilloma is associated with HPV infection in children
• Solitary papilloma is associated with middle to old age with no association to HPV
• Papilloma has a fibro - vascular stalk as a microscopic finding
• Solitary pulmonary nodules have a coin lesion upon US
• The risk of a coin lesion becoming malignant increases over 50 years old
• Causes of Primary Solitary Nodules:

  • Granulomas (e.g. Tbc, Histoplasmosis)
  • Malignancy (primary Cancer)
  • Bronchial (Chondroid) Hamartoma