Revision Practical Final 2 PDF

Revision Macrophages  Neutrophils Eosinophils NB. Neutrophil is the characteristic cell of acute inflammation. Eosinophil is the characteristic cell of allergy and parasitic infestation.  Abscess  Type of inflammation: Acute localized s...

Revision Macrophages  Neutrophils Eosinophils NB. Neutrophil is the characteristic cell of acute inflammation. Eosinophil is the characteristic cell of allergy and parasitic infestation.  Abscess  Type of inflammation: Acute localized suppurative inflammation.  Causative agent: staph.aeurus bacteria that secretes coagulase enzyme  Furuncle  Type of inflammation: Acute localized suppurative inflammation.  A small abscess related to hair follicles  Carbuncle  Type of inflammation: Acute localized suppurative inflammation.  Abscess cavity draining pus through several openings.  Site: Back of neck and buttocks.  Risk factor : D.M  Cellulitis  Type of inflammation: Acute diffuse suppurative inflammation.  Causative agent: Strep. Hemolyticus bacteria that secretes fibrinolysin and hyaluronidase enzyme  More common in diabetic patients  Pseudomembranous Catarrhal inflammation inflammation  Type of inflammation: Acute non - suppurative inflammation.  Serous inflammation Fibrinous inflammation  Type of inflammation: Acute non - suppurative inflammation.  Type of inflammation: Acute non - suppurative inflammation.  Granuloma Def.: Granulomatous inflammation is a form of chronic inflammation characterized by collections of activated macrophages, often with T lymphocytes, and sometimes associated with central necrosis.  The activated macrophages may develop abundant cytoplasm and begin to resemble epithelial cells, and are called epithelioid cells. Some activated macrophages may fuse, forming multinucleate giant cells.  Tuberculosis Caseating granuloma Friable yellowish cheese like caseous material  Caseation Epithelioid cells Langhans giant cell Langhans giant cell  Caseation Langhans giant cell Microscopic picture of tuberculoid granuloma: Tubercle (caseating granuloma) Epithelioid Langhans giant , central caseation necrosis, cells cells surrounded by epithelioid histiocytes , Langhans giant cells, rim of lymphocytes and fibroblasts.  Granulation tissue It is the tissue initially seen at the site of healing. Gross picture: Soft, pink, granular tissue that seen under the scap. It easily bleeds on touch. Microscopic Picture: -proliferating fibroblasts -loose edematous connective tissue stroma -New blood vessels -Scattered chronic inflammatory cells  Fibroblasts Inflammatory cells Newly formed vessels Newly formed blood vessels  Hypertrophic scar &keloid  Gross picture:  Hypertrophic scar: Not extend beyond site of wound.  Keloid which extend beyond the boundary of original wound.  Both hypertrophic scar and keloid are examples of excessive healing with excessive collagen deposition. Hypertrophic scar Keloid  Metaplasia Squamous Metaplasia:  Occurs in in the respiratory epithelium of habitual cigarette smokers, in whom the normal respiratory of the trachea and bronchi often are replaced by stratified squamous epithelial cells.  Also occur in urinary tract in settings of chronic irritation as stones or bilharziasis. Transitional epithelium of urinary bladder change into stratified squamous epithelium.  It occurs in the endocervix in case of chronic cervicitis with change of endocervical epithelium into squamous epithelium.  Squamous epithelium Transitional epithelium Squamous metaplasia in urinary bladder Squamous metaplasia of endocervix in a setting of chronic cervicitis with sq. epithelium overrides endocervical glands Columnar/Intestinal Metaplasia: Barrett esophagus: Intestinal metaplasia  sq. epithelium change into columnar or intestinal epithelium).  Secondary to prolonged gastroesophageal reflux (GERD).  Reversible cell injury Cloudy swelling  Reversible cell injury characterized morphologically by swelling of the cells (due to water accumulation) and granularity of the cytoplasm usualy caused by hypoxia. Microscopic picture: Swollen cells with eosinophilic granular cytoplasm. Cloudy swelling, the tubular epithelial cells showed swelling, granular eosinophilic cytoplasm Fatty change Fatty liver, enlarged, soft yellowish, rounded borders and tense capsule Fatty change, Hepatocytes with signet ring morphology due to intracellular accumulation of fat globules  Necrosis Coagulative necrosis: Cause: Ischemia and infarction of all organs except the brain Area of coagulative necrosis appears triangular with the base towards periphery Coagulative necrosis of renal tissue showed preserved architecture Fat necrosis: Cause: -Enzymatic fat necrosis as in acute pancreatitis -Traumatic fat necrosis Chalky white appearance of fat necrosis in pancreatitis 5-Fibrinoid necrosis: Cause: special form of necrosis seen in immune reactions in which complexes of antigens and antibodies are deposited in the walls of blood vessels (occurs in vasculitis). Gross Picture: Not evident at gross level Microscopic picture: Bright pink, amorphous appearance on H&E preparations called fibrinoid. Fibrinoid necrosis: Cause: special form of necrosis seen in immune mediated vasculitis. Bright pink deposits in wall of blood vessels with fibrinoid necrosis  Hyaline change Hyaline casts in renal tubules Russel bodies: Hyaline change in plasma cells  Neoplasia Hamartoma  It is a mass of disorganized tissue in a particular site (normally present at this site) , such as the lung or the liver.  Lung Hamartoma Lung mass formed of disorganized growth of cartilage, blood vessels, respiratory epithelium and finbroblasts  Choriostoma  It is a congenital anomaly consisting of a heterotopic nest of cells (not normally present at this site). Lingual Choriostoma showing heterotopic gastric tissue  Gross Picture Benign Malignant 1-Solid organ: A well circumscribed 1-Solid organ: Ill-defined infiltrating mass, capsulated or pseudo-capsulated mass with non-capsulated with hemorrhage and homogenous cut section. necrosis on cut section 2- Hollow organ: Sessile or pedunculated 2- Hollow organ: polyp Fungating cauliflower mass Mass infiltrating the wall Malignant ulcer with irregular outlines, raised everted edges, necrotic floor and indurated base Malignant breast mass: Ill-defined infiltrating mass Excision of the mass+ safety margin Malignant intestinal mass: Fungating cauliflower mass Malignant mass infiltrating colonic wall cause thickening of the wall and narrowing of lumen Malignant gastric ulcer with raised everted edges and necrotic floor Malignant ulcer with raised everted edges  Squamous cell Papilloma Squamous cell papilloma of hard palate: Exophytic soft cauliflower mass with bosselated surface Multiple squamous cell papillomas: Exophytic soft cauliflower masses with bosselated surface Squamous cell papilloma of upper eyelid: Exophytic soft cauliflower mass with bosselated surface  Hyperplastic stratified squamous epithelium Branched fibrovascular core Squamous cell papilloma formed of branched papillary fibrovascular core covered by hyperplastic squamous epithelium Koilocytopathic changes in squamous papilloma denoting viral etiology (HPV) Koilocytopathic changes in squamous cell papilloma caused by HPV in the form of clear cytoplasm and resin nucleus  Intestinal Adenoma It is a benign premalignant neoplasm of intestinal epithelium.  Gross picture: -Appears as polyp either sessile or pedunculated.  Microscopic picture:  Proliferated glands exhibiting cytologic dysplasia Sessile polyp Pedunculated polyp Tubular adenoma with low grade Villous adenoma with moderate dysplasia dysplasia  Lipoma Lipoma: A capsulated lobulated mass with homogenous yellow cut-section  Mature fat cells Fibrovascular septa Lipoma formed of lobules of mature fat cells separated by fibrovascular septa  Intramural Subserous Submucous Leiomyoma Submucous leiomyoma projecting into Intramural leiomyoma with charaacteristic uterine cavity whorly cut section Smooth muscle cells with blunt ended nuclei Leiomyoma formed of Intersecting bundles of smooth muscles  Chondroma Chondroma: Multiple nodules of benign looking cartilage Chondroma: Benign looking chondrocytes arranged in their lacunae  Squamous cell Carcinoma  Precursor lesion: Squamous cell carcinoma in situ By definition require full thickness high grade epithelial dysplasia without invasion of basement membrane. Insitu SCC showing full thickness epidermal dysplasia Well differentiated squamous cell carcinoma with abundant keratin pearls  Keratin Cell nest pearl Well differentiated SCC with abundant keratin pearls  Conventional adenocarcinoma (colon) Well differentiated intestinal adenocarcinoma showing malignant glands Well differentiated intestinal adenocarcinoma showing malignant glands with necrotic debris in the lumens  Mucinous adenocarcinoma  Def.: These are malignant tumors of glandular epithelium characterized by abundant mucin production. There are two types of mucinous carcinoma: 1.Carcinoma (mucoid or colloid Carcinoma): This is an adenocarcinoma with abundant extracellular mucin secretion, 2. Signet Ring Cell Carcinoma: The malignant cells show intracytoplasmic mucin that pushes the nuclei eccentrically.   Microscopic picture: There are two types of mucinous carcinoma: 1.Carcinoma (mucoid or colloid Carcinoma): This is an adenocarcinoma with abundant extracellular mucin secretion, which appears as pale mucinous pools with floating malignant glands embedded into it. 2. Signet Ring Cell Carcinoma: The malignant cells show intracytoplasmic mucin that pushes the nuclei eccentrically. No acinar differentiation. The prognosis of this neoplasm is poor. Mucoid carcinoma showing malignant acini floating in mucin lakes  Signet ring cells Signet ring carcinoma showing signet ring cells with intracellular mucin Fibrosarcoma Fibrosarcoma showing characteristic herring bone pattern Fibrosarcoma showing characteristic herring bone pattern  Basal cell carcinoma  Locally aggressive tumor Rodent ulcer with beaded rolled in edges  Epidermal connection Nest of basaloid cell with peripheral palisading Nests of basaloid cells with peripheral palisading and retraction artifact