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