General pathology Lab 1

Inflammation

Signs of acute inflammation

1. Heat (Calor)

2. Redness (Rubor)

3. Swelling (Tumor)

4. Pain (Dolor)

5. Loss of function

(Functio laesa)

Microscopic view showing vascular dilation, edema and leukocytic infiltrate

Acute inflammation shows (1) the submucosa contains dilated &congested capillaries (thick arrow).(2)The interstitial connective tissue is pale &edematous due to the presence of inflammatory exudate(3)Polymorphs(double arrow) arevisible within capillaries(margination) , as well as in thesubmucosa & within the surfacestratified squamous epithelium (migration).

Acute inflammation of the conjunctiva showing swelling and

redness of both eyelids

Microscopic view showing showing

congested blood vessels with interstitial

edema and acute inflammatory cells

infiltration. مهمه كثيير

Microscopic view showing severe acute inflammation (neutrophilic exudate)

leukocytic cells margination in a dilated congested blood vessel

مهم عنها وحكت عليها الدكتورة ركزت Macrophage

Phagocytosis of cells shows numerous very large phagocytic cells (thin arrow ), the nuclei of which are very large, pale (thick A) &

in their abundant cytoplasm are many ingested pyknotic, necrotic cells &lymphocytes (Double arrow ).

Acute lymphadenitis

Acute lymphangitis

Photographic view showingacute lymphadenitisi.e. inflammed draininglymph vessels كثيير مهمة

الصورة هاي

Acute lymphadenitis.Inflammation of the draininglymph nodes to site of injury.

Serous inflammation

Skin blister

Serous inflammation: Sub epidermal bullous. Theepidermis is separated from the dermis by a focal collection of serous effusion.

Skin blisters following burnGross view of bilateral pleural clear serous fluid , example of serous inflammation

Fibrinous inflammation

Fibrinous pericarditis.

Deposits of fibrin on

the pericardium.

Pink meshwork of fibrin

exudate (F), overlies

pericardial surface(P).

Uraemic pericarditis: heart.

Fibrinouspericarditis.

The epicardial surface is

covered with grey-white strands

of fibrin some of which appear

contracted& white as a result of

organization (so-called, bread &

butter appearance).

Gross view of chronic fibrinouspericarditis, showing bread & butter appearance .

Suppurative inflammation

Purulent meningitis. The under surface of the brain is shown . A thick green purulent exudate

(Pus) fills thesubarachnoid space over the brain-stem & cerebellum. The patient had acute

meningitis caused by staphylococcusaureus.

Purulent exudate

Acute suppurative tonsilitis , the tonsils

being covered by whitish yellowish

material (pus)Skin pustule (abscess) composed mainly of neutrophils

Microscopic view of Purulent inflammation.A.Multiple bacterial abscesses in the lung(arrows) in a case of bronchopneumonia.B, The abscess contains neutrophils + cellular debris=Pus, is surrounded by congested blood vessels.

Membranous or Pseudo-membranousinflammation

Membranous

inflammation seen in

Diphtheria

Pseudo-membranous colitis

Microscopic view of pseudo-membranous colitis: mushroom-like membrane

Lymphocyte

Neutrophil

Macrophage

Eosinophil

A,

Chronic lung inflammation, showing collection

of chronic inflammatory cells (asterisk) +

destruction of parenchyma (normal alveoli are

replaced by spaces lined by cubical

epithelium, arrowheads), + fibrosis

B,

Acute bronchopneumonia .

Showing neutrophils filling the alveolar spaces

with congested blood vessels

Chronic colitis showing dense lympho-plasmacytic infiltrate

Lymphocytes ( Red & blue arrows). Histiocyte(macrophage) (Green arrow)

Macrophages:The section shows mainly very large activated macrophages, each with a single vesicular nucleus & abundant granular & vacuolated cytoplasm. Some macrophages contain ingested RBC, polymorphs & cell fragments (Thick arrow). Neutrophils seen ( thin arrow) .

Plasma cells

Eosinophil

Granulomatous inflammation

pattern of chronic inflammation.

Composed of multinucleated giant cells surrounded by epithelioid histiocytes and lymphocytes.

Multinucleated giant cells

Foreign body type giant cell granuloma around sutures

Caseating tuberculous granuloma showing central caseous necrosis (pink) with peripheral epithelioid cells & Langhans giant cells (arrows), with lymphocytes & fibrosisمهمة وايد وايد وايد

Chronic brain abscess ,its inner wall of is covered with grayish-green pus .The abscess is enclosed by a fibrous capsule , the brownish rim is a granulation tissue (arrows).

Ulcer

It is a localized loss of epithelial surface (skin or GI lining).

Ex: Aphthus ulcer.

Gummatous ulcer (syphilis) : A large ,deep ulcer of the abdominal

wall skin. The ulcer base is covered by a necrotic slough.

Morphology of an ulcer .A, gross appearance of

chronic duodenal ulcer.

B, Low power viewOf the ulcer crater (pit) with an acute inflammatory exudatein the base.

Chronic gastric ulcer هاي الصورة كثيير مهمة

TB ulcer: ileum A circumferential ulcer . Contraction of the ulcer scar tissue may produce a localized stricture, with intestinal obstruction, and dilatation of the proximal segment (right of the figure). هاي الصورة مهمة كمان

Bronchial mucosa showing basement membrane(arrows)

Renal glomerulus showing basement membrane (pink colored)

Tissue repair

From residual uninjured cells or stem cells

Liver cirrhosis: Liver section stained by reticulinstain. There are three regenerative

liver nodules (double arrow), separated by broad bands of reticulin fibers (thick

arrow).An exampleof healingby combineregeneration& fibrosiswhich follows injury

to the livercells& stroma.

Primary intention(union)

Primaryintention

Secondary intention: excessive granulation tissue

Hemostasis Inflammation

Granulation tissue formation

Scarformation

Granulation tissue: proliferative fibroblasts, delicate vascular channels and mixed

inflammatory cells.

The healed wound is visible as a ‘gap’ in the stroma, filled with a connective tissue & many fibrocytes (double A), the epithelium covering the gap in it (thin A) is much thinner than the normal epithelium on each side of the wound.

A:Granulation tissue showing

numerous bloodvessels, edema,

& a loose ECM;

minimal mature collagen .

B:Trichromestain of maturescar,showing densecollagen(blue) with only scattered vascular channels.

هذول الصورة مهمات ركزوا

عليهم

2ry healing by excessive tissuenecrosis

Healing of skin wound by secondary intention

Healing by secondaryintention :showing a largeirregular permanent scar.

Hypertrophicscar

Keloid

Keloid: excess collagen deposition

A, Excess collagen deposition in the skin

forming a raised scar known as a keloid

B, Thick collagen deposition in the

dermis ( pink color).

مهمات

جدا جدا

جدا

Excess collagendeposition

Exuberant granulation tissue followingburn

Foreign-body granuloma :

healed wound of skin ,

showing granulation tissue,

consisting of (1) large

&greatly dilated capillaries,

(2) lymphocytes & plasma

cells, (3) fibroblasts (thin

arrow), (4) very large giant

cells enclosing nylon suture

material, (thick arrow ) from

the original surgical incision

Kidney scarring following infarction.

Healing of diabetic skin ulcer