Respiratory Histology and Anatomical Pathology

This set covers the histological characteristics of the respiratory system and common pathological findings in lung diseases like TB, emphysema, and carcinoma.

Epiglottis

A structure containing elastic cartilage with a laryngeal surface lined by ciliated pseudostratified columnar epithelium (respiratory epithelium).

Trachea

An airway characterized by ciliated pseudostratified columnar epithelium, hyaline cartilage with perichondrium, mixed glands, and a lamina propria.

Bronchus

An intrapulmonary airway that contains hyaline cartilage, mixed glands, smooth muscle, and ciliated pseudostratified columnar epithelium.

Bronchiolus

A small airway that lacks cartilage and glands but contains smooth muscle and ciliated pseudostratified columnar epithelium.

Bronchiolus Terminalis

The final portion of the conducting airway, lined with simple columnar epithelium.

Bronchiolus Respiratorius

An airway where gas exchange can begin, lined with simple cuboidal epithelium.

Stigma

An opening or hole that serves as a connection between neighboring alveoli.

Pneumocyte Type I (Alveolar Type I Cell)

Alveolar cells characterized by flat (squamous) nuclei.

Pneumocyte Type II (Septal Cell)

Cuboidal alveolar cells with round nuclei that bulge into the alveolar lumen.

Dust Cells (Lung Macrophages)

Phagocytic cells in the lung that appear darker or black in histological sections.

Tuberculosis Paru (Macroscopic Appearance)

Lung tissue showing hard, yellowish sections that resemble cheese.

Langhans Giant Cells

Multinucleated cells with nuclei arranged in a horseshoe shape, found in tuberculosis lesions.

Epithelioid Cells

Modified macrophages that resemble epithelial cells, typically found in granulomatous inflammation like TB.

Caseous Necrosis

A form of cell death characteristic of tuberculosis that appears cheese-like macroscopically.

Emphysema (Macroscopic Appearance)

Dilation of the alveoli that causes the lung tissue to appear like a sponge.

Emphysema (Microscopic Appearance)

Histologically characterized by widened alveoli containing erythrocytes and pigmented phagocyte cells.

Primary Lung Carcinoma

Lung cancer characterized by pleomorphic and hyperchromatic nuclei, glandular or papillary (labyrinth-like) structures, and a total lack of normal alveoli.

Secondary Lung Carcinoma

A metastatic lung cancer characterized by multiple small tumor masses (multiple lesions) and the presence of normal air-filled alveoli among the tumor cells.

Pneumonia

A lung condition where alveolar walls thicken, and the alveolar spaces are filled with fibrin and polymorphonuclear (PMN) leukocytes.