One Lecture (2) Hours
Lab section for slide examination (2) section (2) Hours each
Museum section for Gross Pathology Examination (2) section (2) Hours each
Students must learn
How to describe gross pathological specimens
An orderly, systematic method of examining and describing specimens is of great importance in pathology. First you have to recognize the type of tissue present, then describe in a simple way how the specimen differs from the normal and lastly pathologically interpret these differences
Normal anatomy
In many specimens, the organ or part of the body affected can be recognized and described. We describe the specimen with the presented lesion (tumor or the cyst). Comment should cover the following items
Site: site of the mass or cyst in relation to the organ
Size: (relative size in cm)
Shape: Rounded, oval, kidney-shaped or irregular
Surface: Smooth, granular, nodular or lobular
Color: yellowish, whitish, grayish or grayish white
Capsule: Capsulated or not-capsulated (mainly for tumors)
Cut section: Cystic or solid and other degenerative change)
Consistency: Soft, firm or hard
Presence or absence of hemorrhage and necrosis
The specimens have to be described from outer surface and cut section
Difference of the pathological specimens from normal counterpart
Describe the lesion in simple words, e.g. the specimen is a slice of liver which contains a rounded well capsulated mass of 5 cm in diameter, stating the site, size, shape, color of the lesion……etc
Pathological interpretation of the described changes
From a given description, the diagnosis is obvious in some cases. In others, the diagnosis is not possible from the gross appearance alone, and a differential diagnosis is necessary
Most of the lesions usually fall under one of the following headings
Congenital malformation
Traumatic lesions
Inflammatory (acute) or chronic
Degenerative changes
Circulatory disturbance
Obstructive disease
Nutritional, metabolic, or endocrinal disorders
Haemtopiotic disorders
Tumors
Benign
Malignant (primary or secondary)
By discussing this list, we can reduce the number of possibilities and identify the most appropriate diagnosis. When several possibilities are suspected, microscopic examination can differentiate between them
HOW TO EXAMIN A SLIDE
Examine the glass slide by naked eye
Use the microscope to examine the slide by low power lens
Use the high power lens to study the details of the cells and tissue
ACUTE INFLAMMATORY CELLS
Neutrophiles or PML
Pus cells: Dead and fragmented neutrophils
Macrophages
CHRONIC INFLAMMATORY CELLS
Lymphocytes
Plasma cells
Macrophages
Eosinophiles
Fibroblasts
Giant cells
HOW TO DESCRIBE A PATHOLOGICAL SECTION
Microscopic description of an organ should be systematic to cover all structural components
For liver sections: Comment should include covering peritoneum (normal or thick), lobular architecture (normal or distorted), central vein (normal or dilated), portal tracts (structure and presence of any lesions), hepatocytes (describe size, arrangement, their nuclei and cytoplasmic inclusions) and the sinusoids
For renal sections: Glomeruli, tubules, afferent and efferent arterioles and interstitial tissue should be evaluated and any change should be documented
For pulmonary sections: Comment should cover the alveolar spaces, alveolar capillaries and alveolar walls
Stomach and GIT: Comment on mucosa, mucosal glands, submucosa, musculosa and serosa
For tumors: Three items should be evaluated:Pattern of growth or tumor tissue morphology: tumor cells can grow in tubules, cell nests, solid sheets cords or singly. Cellular criteria: cell size, cell shape, nucleo-cytoplasmic ratio (N/C ratio), nucleus, nucleolus, mitosis and cytoplasmic contents (mucin, fat ….. ect). Stroma: vascularity, desmoplasia (fibrosis), presence of secretion, hemorrhage and necrosis
Overall Aims or Objectives of the Course
By the end of this course the student should be able to
Gain the basic knowledge and understanding of general and systemic pathology
This includes diseases etiology, participating factors, pathogenesis, pathological features (gross & microscopic), fate, complications & prognosis
Understanding the disease process to be able to correlate the clinical manifestation with the pathological changes
To predict the course & outcome of the disease
To realize the role of histopathology & cytology in the diagnosis of diseases