Pathology 🩺 Flashcards
What is the definition of pathology?
Is the science which deals with the study of diseases.
What does the study of pathology include?
ENCF PPPP
1) Etiology.
2) Nature of the disease.
3) Pathogenesis.
4) Pathological examination of lesions.
5) Prognosis.
6) Complications.
7) Fate.
8) Pathological investigations.
What is etiology?
This means the cause of the disease.
What does etiology include?
-Predisposing factors
-Exciting factors
Predisposing factors
-Factors that help the development of the disease.
-This occurs in one of two ways:
1) Decreased body defense (favors infection).
2) Increased susceptibility (suggested to be hereditary) as Bronchial asthma.
Exciting factors
-Is the direct cause of the disease (i.e. cause lesion).
-It includes:
1) Defective fetal development in the uterus:
Congenital.
Hereditary (genetic). “Like Trisomy 21”
2) Acquired factors (after birth):
Exogenous (environmental) factors as microbes, nutritional deficiency (protein, vitamins, etc.)
Endogenous (internal factors) as endocrine disturbance, hypertension, peptic ulcer.
What can the nature of the disease be?
-Congenital & Hereditary diseases.
-Acquired diseases:
Inflammation.
Degeneration. “Diseased but not dead”
Circulatory disturbance. “Disturbance in CVS”
Tumors.
What is pathogenesis?
The mechanisms by which the causative agent produces the pathological changes in the tissues (i.e. mechanism of formation of the lesion.).
Pathological examination of the lesions
Structural changes in the diseased tissues include:
Gross picture (macroscopic picture): A naked eye description of the pathological changes.
Microscopic picture (histological): These are the changes in the tissues of organs detected on microscopic examination by Light microscope, Electron microscope, and Immunohistological techniques
What is an example of an immunohistological technique?
as immunofluorescence technique by the use of antibodies to various constituents of human cells and their products.
What is the prognosis?
Is the forecast of the course & termination of a disease.
What are “complications”?
-Are additional pathological changes which may occur during or after the termination of the usual course of the disease.
-They affect or modify the prognosis of the disease.
What is the definition of “fate”?
It includes prognosis & complications of the disease.
What do the pathological investigations include?
-Biopsy: This is the study of a specimen from the lesion during life.
-Autopsy: This is a post-mortem examination of the cadaver.
What is the difference between congenital and hereditary diseases?
-Congenital disease: normally fertilized ovum is affected in the uterus by microbes, drugs, X-rays, etc.
-Hereditary (genetic disease): inherited from parents.
What are lesions?
The structural changes occurring in the tissue as the result of the disease are called lesions.
How are the material obtained for pathological investigation preserved?
The materials obtained are put immediately in a fixative fluid to prevent autolysis, mainly 10% formalin.
What does surgical pathology involve?
Surgical pathology involves gross and microscopic examination of surgical specimens, as well as biopsies submitted by clinicians.
What does the practice of surgical pathology allow us for?
definitive diagnosis of disease in removed tissue.
How is surgical pathology performed?
This is usually performed by a combination of:
Gross (Macroscopic) examination of the tissue.
Histopathologic (Microscopic) examination.
Molecular studies (immunohistochemistry).
What are the types of spicemens?
-Excision biopsy
-Incision biopsy
-True-cut Biopsy
-Fine Needle Biopsy
-Aspiration of body fluids
Excision Biopsy
Therapeutic surgical resection (TSR) of the entire lesion
Incision biopsy
Surgical resection of part of the lesion for diagnosis.
TRUE-CUT BIOPSY
The core of tissue is obtained by the use of large-bore needles, sometimes under the guidance of radiological techniques.
FINE NEEDLE ASPIRATION
Fluid aspiration from the lesion tissue by a fine needle for cytologic smear preparation and examination of aspirated cells.
Aspiration of body fluids
For cytologic smear preparation & examination (as urine, ascites…)
Fixation
-Immediate specimen fixation is mandatory.
-The widely used fixative is 10% formaldehyde (Formalin) buffered to a neutral ph.
What is the importance of fixation?
1) Fixation will preserve the morphology.
2) Prevent decomposition and autolysis.
3) Minimize microbial/fungal growth.
4) Minimize the loss of molecular components.
Gross examination
LG COLR
1) Recognition of the anatomic landmarks for proper anatomic orientation and measuring specimen.
2) Localization of the lesion.
3) Opening and examination of the whole Specimen.
4) Cutting proper Sections needed for diagnosis (sampling).
5) Labeling sections.
6) Gross description which represents a permanent record of the specimen’s macroscopic features and enables the pathologist to correlate each slide to a precise location on the specimen.
Microscopic examinations
-All samples cut grossly from the specimen should be processed and sectioned on glass slides.
-Sections should be stained by Hematoxylin and Eosin (H&E) for microscopic examination.
-Other special stains could be used.
Immunohistochemistry
-Specific monoclonal antibodies help to identify cell products or surface markers
-Determination of the origin of the cell population.
-Detection of prognostic and therapeutic markers
Intraoperative Consultation
-Rapid microscopic examination of fresh tissue is done for intraoperative consultation which is needed for important decisions during operation.
What are the methods of intraoperative consultation?
Methods:
Preparation of histologic slides using the frozen section technique.
Preparation of cytologic slides.
Developmental abnormalities of cell growth
Occurs due to defective fetal development in uterus.
They manifest at birth or shortly after.
Either hereditary or congenital.
What are the causes of developmental abdnormalities of cell growth?
Hereditary abnormalities:• Inherited from the parents. e.g. Genetic disease
Congenital abnormalities:• Due to affection of the normal fertilized ovum by adverse factors as infection, chemicals, irradiation or an increased maternal age.
What are the congenital disorders of cell growth?
Agenesis
Aplasia
Hypoplasia
Atresia
Heterotobia(choristoma)
Hamartoma
What is agenesis?
Congenital absence of an organ e.g. solitary kidney.
What is aplasia?
The organ is represented by a rudimentary structure
What is hypoplasia?
The organ is a normal structure but fails to reach adult size e.g. kidney.
What is atresia?
• Absence of a normal opening
• Failure of canalization of hollow organ e.g. intestine
What is Heterotobia(choristoma)?
• Presence of normal tissue in abnormal sites
• e.g pancreatic tissue in stomach or thyroid tissue in
the base of the tongue.
What is hamartoma?
• Formation of a mass of mature tissue of the locality, but in abnormal arrangement or quantity as pigmented nevi.
What are the cellular adaptations to stress?
Reversible changes in the number, size, phenotype, metabolic activity, or functions of cells.
What are the types of cellular adaptations to stress?
Physiologic adaptations:-
In response to normal stimulation e.g. by hormones
Pathologic adaptations:-
In responses to stress
What are acquired disorders of growth?
1- Atrophy
2- Hypertrophy
3- Hyperplasia
4- Metaplasia
5- Dysplasia
What is the definition of atrophy?
Decrease in organ size by decrease in size and/or the number of its cells.
What is the classification of atrophy?
Physiological and pathological
What are the types of physiological atrophy?
-General (Senile): It is an aging process.
-Local: Involution of an organ due to loss of its physiologic function. and its causes are (After labor: ↓ uterus, After child weaning: ↓ breast size)
What are the types and causes of pathological atrophy?
-General (Senile)
-Causes
Starvation.
Toxic.
Hormonal.
Local
-Causes
Disuse Atrophy.
Neurogenic atrophy.
Ischemic atrophy.
Pressure atrophy.
Thermal.
What is the gross morphology of atrophy?
General Atrophy
All organs are affected to a variable extent:
1. Skin is wrinkled
2. Loss of fat of adipose tissue
3. Wasting especially of liver, muscles
4. Brown atrophy of heart.
Local Atrophy
The organ is decreased in size and weight.
What is the microscopic morphology of atrophy?
1- Reduction of cytoplasmic mass.
2- The nucleus is apparently normal.
3- Spaces created by atrophied cells are occupied by fibrous tissue or fat.
What is hypertrophy?
Increase in organ size due to increase in the size of its constituent cells.
What is the classification of hypertrophy?
Pathological and physiological
What are examples of physiological hypertrophy?
➢ In response to hormones: Smooth muscles of the pregnant uterus.
➢ Excess functional demand: skeletal muscles in manual workers and
athletes.
What are examples of pathological hypertrophy?
Hormonal:
- Occurs with an excess growth hormone of the anterior pituitary, leading to gigantism and acromegaly.
Excess functional demand:
1- To overcome distal resistance: in hollow organs
2- Compensatory hypertrophy: in paired organs.
What is the term “neoplasia”?
The term “Neoplasia”:-
Neo = new
plasia = creation (growth)
What is the term “Tumor”?
tumor = swelling
What is the definition of neoplasia?
An abnormal mass of tissue which:
1- Grows more rapidly than the normal tissue.
2- Its growth is uncontrolled by the normal growth control mechanisms (autonomous).
3- Competes with the normal tissue for metabolic needs.
What is any tumor composed of?
Cells:
**Which is neoplastic
**May be benign or malignant
**Tumor is named according to it.
Supporting stroma: which is non-neoplastic
What are tumors classified according to?
Tumors can be classified according to:
The cell of origin into:
1- of epithelial origin
2- of mesenchymal origin
Behavior into:
1-benign
2-malignant
3-locally malignant
What are tumors of epithelial origin?
Benign tumors
Papilloma:
From surface epithelium e.g. squamous cell papilloma
And transitional cell papilloma
Adenoma:
From secretory epithelium e.g. tubular adenoma and liver cell adenoma
Malignant tumors
The name of epithelium + carcinoma e.g. squamous cell carcinoma and transitional cell carcinoma and hepatocellular carcinoma
What is papilloma?
Papilloma = benign tumor of surface epithelium.
What is adenoma?
Adenoma = benign tumor of secretory epithelium.
What is carcinoma?
Carcinoma = malignant tumor of epithelium.
What are tumors of mesenchymal origin?
Benign tumors
-The name of mesenchymal tissue + oma
*from fibrous tissue — fibroma
*from cartilage ——— chondroma
*from bone ————- osteoma
*from fat —————- lipoma
Malignant tumors
-The name of mesenchymal tissue + sarcoma
*from fibrous tissue — fibrosarcoma
*from cartilage ——– chondrosarcoma
*from bone ————- osteosarcoma
*from fat —————- liposarcoma
What is fibroma?
benign tumor of fibrous tissue.
What is fibrosarcoma?
malignant tumor of fibrous tissue.
What Is liposarcoma?
malignant tumor of fat cells.
Compare between benign and malignant tumors
Origin
Growth
N/E
M/E
Prognosis
1- Arise from normal cells.
1- Arise from either normal cells or premalignant lesions.
2- Grow slowly by expansion (i.e. push the surrounding normal tissue without tissue damage).
2- Grow rapidly by both expansion & infiltration (i.e. infiltrate & damage the surrounding normal tissue).
3- N/E:- *single.
*small.
*capsulated.
*no hemorrhage or necrosis.
3- N/E:-
*begin single then spread.
*reach a large size in a short time.
*non-capsulated
*hemorrhage or necrosis
4- M/E:-
**cells: similar to cell of origin, no criteria of malignancy.
**Pattern of arrangement: similar to tissue of origin.
**stroma:
few blood vessels,
no hemorrhage or necrosis.
4- M/E:-
**cells: show criteria of malignancy.
**Pattern of arrangement: depends on tumor grade.
**stroma:
prominent bl. Vs.,
with hemorrhage & necrosis.
5- Prognosis:- **No spread
**No recurrence
**Not harmful except if: *In vital organ
*Obstruct hollow organ *Produce hormone *Turn malignant
5- Prognosis:-
- spread occurs either:
*direct (in surrounding tissue)
*distant metastasis [by blood, lymphatic vessels or through serous sacs (transcoelomic)]
- recurrence occurs (due to infiltrating borders with the absence of capsule)
-harmful due to:
*Organ destruction (infiltration) *Obstruction of hollow organ *Clinical syndromes related to tumor
What is the origin of benign tumors?
Arise from normal cells.
What is the origin of malignant tumors?
1- Arise from either normal cells or premalignant lesions.
How do begin tumors grow?
Grow slowly by expansion (i.e. push the surrounding normal tissue without tissue damage).
How do malignant tumors grow?
Grow rapidly by both expansion & infiltration (i.e. infiltrate & damage the surrounding normal tissue).
What is the N/E of benign tumors?
*single.
*small.
*capsulated.
*no hemorrhage or necrosis.
What is the N/E of Malignant tumors?
*begin single then spread.
*reach a large size in a short time.
*non-capsulated
*hemorrhage or necrosis
What is the M/E of the benign
tumors?
cells: similar to cell of origin, no criteria of malignancy.
**Pattern of arrangement: similar to tissue of origin.
**stroma:
few blood vessels,
no hemorrhage or necrosis.
What is the M/E of malignant tumors?
**cells: show criteria of malignancy.
**Pattern of arrangement: depends on tumor grade.
**stroma:
prominent bl. Vs.,
with hemorrhage & necrosis.
What is the prognosis of benign tumors?
5- Prognosis:-
**No spread
**No recurrence
**Not harmful except if:
*In vital organ
*Obstruct hollow organ
*Produce hormone
*Turn malignant
What is the prognosis of malignant tumors?
- spread occurs either:
*direct (in surrounding tissue)
*distant metastasis[by blood, lymphatic vessels or through serous sacs(transcoelomic)] - recurrence occurs (due to infiltrating borders with the absence of capsule)
-harmful due to:
*Organ destruction (infiltration)
*Obstruction of a hollow organ
*Clinical syndromes related to tumor
What are the Microscopic Criteria of malignancy (not present in benign tumors)?
1- Pleomorphism (variability in size & shape of cells & nuclei).
2- Hyperchromatism (dense chromatin inside the nuclei).
3- increased N/C ratio to 1:2 (instead of 1:4 in normal cells).
4- Tumor giant cells.
5- Atypical (abnormal) mitoses.
6- Prominent nucleoli.
What is a Tumor grade?
It means the degree of similarity of tumor tissue to the tissue of origin regarding morphology & function (i.e. how much the tumor resembles the normal tissue).
What are the grades for any tumor?
1- Grade I (well-differentiated tumors).
2- Grade II (moderately differentiated tumors).
3- Grade III (poorly differentiated tumors).
4- Grade IV (undifferentiated tumors = anaplastic tumors)
What is the definition of locally malignant tumors?
These are tumors characterized by:
1- Grow by local infiltration.
2- No blood or lymphatic spread.
3- Microscopically show criteria of malignancy.
4- Recur after incomplete removal
5- May turn malignant.
What are the examples of Locally malignant tumors?
1- Adamantinoma of mandible.
2- Basal cell carcinoma of the skin.
3- Craniopharyngioma of the pituitary gland.
4- Carcinoid tumor.
5- Giant cell tumor of bone.
What does the tumor grade estimate?
It estimates the tumor aggressiveness.
What is the tumor stage?
It is based on 3 items: [TNM staging system]
1- the size of the primary tumor.
2- presence or absence of lymph node spread.
3- presence or absence of metastasis (distant spread).
What is the definition of hyalinosis (hyaline degeneration)?
Glassy Refractile Homogenous Structurless Transparent material with unknown nature that stains Red with Eosin.
What are the types of hyalinosis?
Intracellular hyalinosis
1. Corpora Amylacia: Prostate
2. Russell bodies: Plasma cells in Rhinoscleroma
3. Old thrombi
4. Mallory body “Apoptotic bodies”: in Alcoholic
hepatitis
5. Councilman body: in Viral hepatitis (Yellow fever)
Extracellular hyalinosis
A. Vascular:-
1. Artery: Atherosclerosis
2. Arteriole: Spleen in Old age, Hypertension
B. Extra-vascular:-
1. Old scar
2. Spleen capsule & trabeculae
What are the sites, examples, and M/E of mucinous & myxomatus degeneration?
Sites:-
-Epithelial “Mucinous - Mucoid”
-Connective tissue “Myxomatous”
Examples
-Catarrhal inflammation, Mucoid adenocarcinoma
-Myxoma “CT tumor”, Myxedema
M/E
-none
-Star-shaped cells separated by pale blue mucin
What is the definition of amyloidosis?
Abnormal deposition of protein substance in between cells and in blood vessels in different tissues and organs.
What is the morphology of amyloidosis?
N/E: Waxy Translucent
M/E: Homogenous Structurless Red material (Like Hyalinosis & Fibrinoid necrosis)
What are the stains of amyloidosis?
Gross stains
1) lodine: Brown
2) lodine with sulphoric acid: Blue
Microscopic stains
1) Congo red: When viewed under polarized light it gives Apple Green birefringence
What are the types of systemic amyloidosis?
1) Immunocyte dyscrasias with amyloidosis “Primary amyloidosis
2) Reactive systemic amyloidosis “Secondary amyloidosis”
3) Heredofamilial amyloidosis
Where is Immunocyte dyscrasias with amyloidosis “Primary amyloidosis” seen in and what is its site, and cause of diseases?
-Seen in:
Multiple Myeloma (Plasma cell tumor).
-Site:
a) Early in Muscle - Heart - GIT “Alimentary tract”.
b) Late in: Solid organs.
-Cause of Death:
Heart failure - Renal failure
Where is Reactive systemic amyloidosis “Secondary amyloidosis” seen in and what is its site, and cause of diseases?
-Seen in Chronic inflammatory lesions with continuous breakdown (TB - Rheumatoid arthritis).
-Site: Early in Solid organs.
- Cause of Death: Renal failure.
Describe Heredofamilial amyloidosis
Familial Mediterranean Fever “FMF” characterized
by recurrent inflammations of Joints & Serous sacs.
What are examples of localized amyloidosis?
1) Senile Cardiac Amyloidosis
2) Senile Cerebral Amyloidosis “Alzheimer disease”
3) Medullary Thyroid Carcinoma MTC
4) Nodules in Skin - Tongue - Larynx - Lung - Urinary bladder
What is the N/E of any organ with amyloidosis?
V Size: Enlarged
V Shape: Preserved
V Surface: Smooth
V Consistency: Firm
V Color: Pale Greyish-brown
V Edges: Sharp edges
What is Gout “Hyperuricemia”?
Disturbance of Purines in nucleoprotein metabolism.
What is the pathology of Gout “Hyperuricemia”?
In joints:-
1. Recurrent attacks of acute arthritis.
2. Chronic gouty Tophi: Joints - Eyelid - Cartilage of ear.
In kidney:-
1. Urate stones
2. Chronic renal failure
What is pathological calcification?
Deposition of Ca salts in tissues other than bone & teeth.
What is the N/E of pathological calcification?
Dull opaque - White - Hard - Finely granular surface.
What is the M/E of pathological calcification?
Dark blue with Hematoxylin.
What is the classification of calcification?
- Dystrophic calcification
- Metastatic calcification
- Stone formation (Urinary tract - Biliary tract - Duct of the salivary gland - Appendix).
Dystrophic calcification
Ca level:
Type of tissues:
Sites:
-Ca level: Blood Ca is normal
-Damaged tissues are more liable to Ca deposition (Hyalinosis & Necrosis).
-Sites:- Degenerated tissue: Old scar - Wall of chronic abscess and necrotic tissues
Metastatic Calcification
Ca level:
Type of tissues:
Pathogenesis (causes of hypercalcemia)
- Blood Ca is elevated
- Deposition in normal tissues
-1. Excess mobilization of Ca from bone:-
a) Bone destruction (Multiple myeloma - Secondary Bone tumors)
b) Hyperparathyroidism
c) Prolonged immobilization
- Excess absorption of Ca from intestine:-
a) Hypervitaminosis D
b) Increased Milk intake - Sarcoidosis
What is hemosiderosis?
Pathological accumulation of Hemosiderin (Localized - Generalized)
How does hemosiderosis take place?
Fe is absorbed from duodenum - Carried in plasma trans-ferritin, Stored as Fe or Apo-ferritin in macrophages in Liver - Spleen - BM.
What is the definition of localized hemosiderosis?
Local accumulation of hemosiderin.
What are the causes of localized hemosiderosis?
Occurs around areas of hemorrhage as in:-
a) Interstitial hemorrhage.
b) Chronic venous congestion of the lung.
What is the def of generalized hemosiderosis (hemochromatosis)?
Generalized increase of hemosiderin.
What are the causes of generalized hemosiderosis (hemochromatosis)?
Iron overload due to:-
1) Over-dose of iron intake.
2) Prolonged iron therapy.
3) Increased iron absorption.
4) Repeated blood transfusions.
5) Hemolytic anemias
What is the pathology of Generalized Hemosiderosis(Hemochromatosis)?
The pigment is deposited in Liver cells - Pancreas - Skin - Heart - Other organs:-
1) Skin: Bronzed color.
2) Pancreas: Diabetes mellitus.
3) Liver: Develops Pigmentary cirrhosis.
4) Heart: Fibrosis - Arrhythmia - Cardiomyópathy - Heart failure.
What is the N/E of Generalized Hemosiderosis(Hemochromatosis)?
The affected organs are Enlarged - Brown - Hard.
What are the types of pigments?
Types of pigments:-
1. Exogenous:-
a) Inhalation: Pneumoconiosis due to Silica.
b) Ingestion: Melanosis coli - Chronic lead poisoning.
c) Inoculation: Tattooing
- Endogenous:-
a) Melanin
b) Hemoglobin derived pigments
What are increased melanin pigments?
- Prolonged exposure to the sun: Stimulation of MSH (Melanocyte Stimulating Hormone)
- Addison’s disease.
- Chloasma of pregnancy: Pigmentation around Nipple - Face - Vulva during pregnancy.
- Tumors; Melanoma.
- Chronic irritation
What are decreased melanin pigments?
- Albinism: Partial or Complete absence of tyrosinase.
- Leukoderma (Congenital).
- Vitiligo (Acquired).
What is the definition of inflammation?
-Inflammation is a complex reaction of a tissue and its microcirculation to a pathogenic insult.
-It is characterized by the generation of inflammatory mediators and movement of fluid & leukocytes from the blood into extravascular tissues.