Pathology of the Respiratory System Flashcards

A comprehensive set of vocabulary flashcards covering various respiratory pathologies, their definitions, macroscopic and microscopic characteristics, and causative factors as discussed in the lecture notes.

Pseudomembranous tracheitis

A rare, severe inflammatory condition of the trachea characterized by the formation of a thick pseudomembrane (composed of fibrin and neutrophils) over the airway lining, which can block the airway.

Corynebacterium diphteriae

The causative pathogen associated with the formation of a brownish-grey, thick, and granular pseudomembrane in the trachea.

Bronchopneumonia

Acute focal suppurative lung inflammation affecting the bronchi, bronchioles, and surrounding alveoli, characterized by small purulent foci scattered throughout the lung lobes.

Spotted lung (dystelectasis)

A macroscopic appearance of the lungs in bronchopneumonia characterized by an alternation between yellow-gray patchy consolidated areas and pale gray normal spongy parenchyma.

Red hepatization

A stage of lung congestion evolution where the lung has a red, firm, liver-like consistency due to hyperemia, extravasated erythrocytes, fibrin, and neutrophils.

Gray hepatization

A stage of lung congestion evolution characterized by a grayish-brown color caused by disintegrated erythrocytes, neutrophils, and fibrin.

Fibrinous pleuritis

An acute inflammatory reaction of the pleura causing the visceral pleura to appear thickened, matt, and rough with fibrin deposits, often spilling outward from an underlying lung infection.

Pleural callus

A dense layer of fibrous scar tissue formed from persistent, long-term inflammation of the pleural membranes, resulting in localized thickening and adhesion.

Anthracosis

The accumulation of carbon pigment in the lungs, making the lung tissue appear dark grey to blackish.

Meconium

The early, first feces passed by a newborn's body, which may be inhaled into the lungs during amniotic fluid aspiration.

Hyaline membrane disease

A developmental respiratory disorder in preterm infants caused by a structural deficiency of pulmonary surfactant, leading to the formation of eosinophilic membranes (fibrin and necrotic cells) in the alveoli.

Interstitial lung emphysema

Overdistension of the lungs caused by alveolar rupture, allowing air to track outside the alveoli through connective tissue septa and under the pleura.

Bullous emphysema

A type of emphysema characterized by large subpleural air-filled cystic-like spaces, or bullae, measuring greater than $1\,cm$ in diameter.

Bronchiectasis

The permanent dilation of bronchi and bronchioles caused by the destruction of smooth muscle and supporting elastic tissue, often resulting in a honeycomb or Swiss-cheese macroscopic appearance.

Miliary pulmonary tuberculosis

A severe, widespread haematogenous spread of Mycobacterium tuberculosis characterized by multiple small ($2-4\,mm$), white-tan foci throughout the lung that resemble millet seeds.

Cavernous pulmonary tuberculosis

A form of secondary TB characterized by the formation of cavities (caverns) in the lung upper pole due to caseous necrosis and destruction of parenchyma.

Laryngeal papillomatosis

A chronic respiratory disease involving recurrent growth of benign, wart-like tumors (papillomas) in the larynx, triggered by HPV strains 6 and 11.

Carcinoma of the larynx

A malignant epithelial tumor, usually squamous cell carcinoma, heavily linked to tobacco and alcohol abuse, presenting as an ulcero-bourgeonnant mass.

Keratin pearls

Diagnostic histological features found in well-differentiated squamous cell carcinoma representing focal keratinization of malignant keratinocytes.

Chondroma of the lung

A rare, benign tumor composed of mature, well-differentiated hyaline cartilage tissue, often appearing as a pearly white-to-cream color nodule.

Carney triad

A rare syndrome involving pulmonary chondromas, gastric gastrointestinal stromal tumors (GIST), and extra-adrenal paragangliomas.

Squamous metaplasia

A reversible, adaptive transformation where normal respiratory pseudostratified ciliated columnar epithelium is replaced by tougher stratified squamous epithelium due to chronic irritation.

Carcinoma in situ (CIS)

The most advanced stage of pre-invasive malignancy involving full-thickness neoplastic transformation of epithelium while the basement membrane remains intact.

Small cell lung carcinoma

A highly aggressive, high-grade neuroendocrine carcinoma arising centrally in the bronchi, characterized by cells with scant cytoplasm, high mitotic rate, and associations with paraneoplastic syndromes.

Kulchitsky cells

The neuroendocrine precursor cells from which small cell lung carcinoma is thought to arise.

Lung adenocarcinoma

The most common histological subtype of non-small cell lung cancer, showing glandular differentiation or mucin production, typically located in the peripheral lung parenchyma.

Desmoplasia

A reactive dense fibroblastic and collagenous stroma/scar tissue formed by the body in response to invasive elements, such as in lung adenocarcinoma.