OSPE Pathology PDF

OLOGY TEA TH M PA OSPE Pathology Special thanks to Abdulaziz Nasser, Abdulaziz Alobathani Color Index: and Khaled AlTameem from med 44 Main text...

OLOGY TEA TH M PA OSPE Pathology Special thanks to Abdulaziz Nasser, Abdulaziz Alobathani Color Index: and Khaled AlTameem from med 44 Main text Dr Question and cases ( very important) Doctor’s Notes Extra info  Case 1 Fibrinoid necrosis R starts 15:03 - 17:00 Pink fibrinous material (Fibrinoid necrosis) Endothelial and inflammatory cells Fibrinoid necrosis in an artery. The wall of the artery shows a circumferential bright pink area of Fibrinoid necrosis with inflammation/ vasculitis (neutrophils with dark nuclei). Fibrinoid necrosis The causes of Fibrinoid necrosis : It usually occurs in immune reactions in which complexes of antigens and antibodies are deposited in the walls of blood vessels, but it also may occur in severe hypertension.  Case 2 R starts in 21:37 - 24:28 Endocervical Squamous Metaplasia Normal Uterine Cervix Gross Appearance: Normal cervix with a smooth, glistening mucosal surface. There is a small rim of vaginal cuff from this hysterectomy specimen. The cervical os is small and round, typical for nulliparous woman. The os will have a fish- mouth shape after one or more pregnancies. Gross Description: 1-From the OS to the outside (Vaginal wall) is composed of Non-keratinized Squamous Epithelium (White arrow). 2-From the hole (OS) to the inside of Uterine Cavity is composed of Columnar Epithelium (Red arrow) Diagnosis Endocervical Squamous Microscopic/ Metaplasia Histological Features The picture (Histology) shows normal endocervical epithelium on the left at (1). And metaplastic squamous epithelium on the right at (2). If there is irritation, Squamous metaplasia will take place  Case 2 cont. R starts in 21:37 - 24:28 Endocervical Squamous Metaplasia (1) Diagnosis (2) (3) Typical Endocervical Squamous Metaplasia (1): Columnar Epithelium (2): Squamous Metaplasia (3): Columnar Epithelium Hypothetical Microscopic Complication If the whole metaplastic A section of endocervix cells (Squamous shows the normal metaplasia) is developed columnar epithelium at into dysplasia that Both margins and a focus involved the entire (full) of squamous metaplasia in thickness, This term is the center called Carcinoma in-situ Note: Cells are Typical not Atypical, because it is only Metaplasia not Dysplasia.  Case 3 Acute cholecystitis R starts in 28:41 - 30:03 It is an acute inflammation of the gallbladder Gross features: 1- Congestion 2- Redness 3- Thickness of the wall 4- Mucocele 5-Stone obstructed the neck 6- distended Aspiration done and removed by laparoscopic cholecystectomy. Histological features 1- Vascular congestion 2- Infiltration of the mucosa and submucosa of gallbladder by many neutrophils. Clinical presentation A Patient with acute cholecystitis presented with right upper quadrant Vascular abdominal pain with tenderness Neutrophils on palpation. Congestion  Extrs info: tuberculous lymphadenitis is a Case 4 type of -IMMUNE MEDIATED GRANULOMAS R starts 39:10 - 40:15 Tuberculous Lymphadenitis Tuberculous Lymphadenitis - Gross Tuberculous Lymphadenitis - Histologic Non caseated inflammation langhan’s giant cells (large cell with multiple peripheral nuclei) Section of a lymph node with connective tissue capsule and lymphoid tissue Mycobacteria with Acid fast bacilli stain CHEESY material Mycobacterium Tuberculosis (Red rods) Many round and oval tubercles/ granulomas with or without central caseation that appears structureless, epithelioid cells homogenous and pink in colour. peripheral rim of lymphocytes Histological features: if there is the type of necrosis what inflammation: A- Epithelioid cells would it be? Chronic granulomatous B- Langhans giant Caseous inflammation cells necrosis C- Peripheral rim of lymphocyte organism causing Stain used to this disease: identify this Gross features: Mycobactirium disease: A-enlarged neck tuberculosis Acid fast bacilli lymph node stain (AFB) B-scarring C-Red streaks  Case 5 start in 42:38 - 44:33 INTRADERMAL NEVUS Macroscopic Appearance (gross) Identify the pictures The lesion is small, slightly raised ,symmetrical (Circumscribed) and uniformly has different colors (Pink – Tan – Brown etc) Microscopic Appearance Melanophages The cells arrange in: Nests and clusters of small round or spindle shaped nevus cells with few melanophages in the upper dermis. the malignant tumor: Melanoma Melanocytes the diagnosis: Intradermal Nevus (Benign) The melanocytes cells contain varying amount of brown melanin pigment. No junctional activity  Questions on Case #1 2 1 What is the affected tissue? Artery. What is the diagnosis ? Fibrinoid necrosis in an artery. Identify the labelled structure: 1- Endothelial and inflammatory cells 2- Pink fibrinous material/ The wall of the artery shows a circumferential bright pink area of necrosis with inflammation. Mention two main causes that lead to this condition? 1-Autoimmune diseases 2- Malignant hypertension Mention two microscopic features: 1-Circumferential bright pink area of fibrinoid necrosis 2- marked/severe inflammation or vasculitis (neutrophils with dark nuclei)  Questions on Case #2 Identify the labelled structures: - Lymphocytes - Blood vessels - Normal cells (normal columnar epithelium) – Squamous Metaplasia Describe what is seen in picture? In the center, focus of squamous metaplasia of endocervix but at the both margin shows the normal columnar epithelium Is it Atypical or not? It’s Typical, just one type of cells replaced by another type (metaplasia not dysplasia) what is the diagnosis? The diagnosis is Typical squamous metaplasia of endocervix When it’s all dysplastic and the dysplasia is involved in the full thickness from basal layer to superficial, the name is : (the form where the biopsy shows atypical squamous cells throughout the entire thickness of the epithelium is called?) Squamous carcinoma in-situ and when invading the basal layer is called malignant tumor What is the cause of this condition? The columnar cells are replaced by squamous cells Mention the microscopical features seen in picture? - normal columnar epithelium at both margins - central focus of squamous metaplasia - lymphocytic infiltration  Questions on Case #3 A 28 year old woman came to the ER with sever pain in the upper right region of the abdomen. The doctor admitted her for immediate excision by surgery. What is the excised organ that shown in the gross picture? Gallbladder Write one gross feature Congestion, redness, thickness of the wall Give two histopathological features in the Histological picture infiltration of many neutrophils in the mucosa of the gallbladder, vascular congestion What is the diagnosis? Acute cholecystitis What is the probable etiology? Stone obstructed the neck Identify the structures pointed in figure 1 Red arrow: vascular congestion Blue arrow: neutrophils  Questions on Case #4 Histological picture Gross picture What is the type of the inflammation here? Chronic granulomatous inflammation Identify the cells in the histological picture epithelioid cells Langhans giant cell Describe what you see in the gross picture: Swelling and scarring. What is the diagnosis? Tuberculous lymphedenitis What is the type of necrosis if present? Caseous necrosis Is the disease caused by a microorganism? If yes What is the causative microorganism? Similar question: what is the etiology of the disease. Yes, Mycobactirium tuberculosis What is the stain used? And color (appearance) Name: Acid fast bacilli (AFB) stain or ziehl neelsen stain Color (appearance) : Red or pink color and rods shape  Questions on Case #5 figure 2 figure 1 Identify the labelled structures in figure 1 Melanocytes (nevus cell) Melanophages What is the diagnosis ? Intradermal Nevus (Benign) What is the malignant tumor? Melanoma What is the characteristic appearance (features) of the cells in figure 2? 1-The cells are small, round, or spindle-shaped, typically arranged in nests and clusters 2-symmetrical (Circumscribed) 3-has different colors (Pink – Tan – Brown etc) Give two histopathologic features: 1-Proliferating benign intradermal melanocytes 2-nevus cells containing melanin pigment.  OLOGY TEA TH M PA OSPE Pathology team Mohammed Fahad Alruwaily Alnoshan Battal Aljohani Ruba aldibas Abdulaziz Noor Mohammed Alshareef Jood Alqosi