TLDR;
Alright guys, so this pathology LRR is gonna be super high-yielding, covering systemic pathology like cardiovascular, respiratory, GIT, liver, renal, and brain. The session also touches upon genital, breast tumors, thyroid, and adrenal glands. Remember, LRR alone ain't enough; gotta club it with RR or main videos for best results. It's for everyone, FMG, NEET PG, INI-CET. Plus, there's a champions exam on the PrepLadder app with audio explanations. PDF with handwritten notes will be shared on Telegram after the session.
- TPTC stains LDH1 in myocardial infarction diagnosis.
- NBTE is associated with mucin-releasing cancers like lung and pancreatic adenocarcinoma.
- Knack syndrome involves fat deposition in the right ventricle, woolly hair, and hypercaratosis.
Cardiac Pathology: Myocardial Infarction and More [6:20]
The session starts with myocardial infarction, diagnosed using TPTC within 4 hours. The first electron microscopic change is mitochondrial swelling, while gross findings like modeling appear after 4 hours. Neutral buffered formalin is the fixative for light microscopy, while 95% ethanol is used for papsmears.
Endocarditis Types and Rheumatic Heart Disease [9:33]
Next up is stroke in a patient with pancreatic adenocarcinoma, likely due to NBTE (Nonbacterial Thrombotic Endocarditis). Rheumatic heart disease features small, warty vegetations caused by Group A beta-hemolytic streptococcus. Infective endocarditis has large, bulky vegetations from various staph and strep species. NBTE is linked to mucin-producing cancers and AML M3, causing embolism. Libman-Sacks endocarditis (LSE) in SLE shows vegetations more commonly on the lower surface of the heart valves. Ashoff bodies, with fibronoid necrosis and Anitschkow cells (caterpillar or owl appearance), are characteristic lesions of rheumatic heart disease.
Cardiomyopathies: Hypertrophic, Dilated, and Restrictive [16:07]
A 22-year-old with exertional chest pain and a family history of sudden cardiac death likely has hypertrophic cardiomyopathy, caused by beta-myosin heavy chain mutation. A basketball player collapsing on the court suggests HOCM (Hypertrophic Obstructive Cardiomyopathy) with interventricular septum hypertrophy and a banana-shaped heart. Titan gene mutation causes dilated cardiomyopathy (DCM), showing ninja star appearance. Takotsubo cardiomyopathy involves left ventricle dilation due to stress and increased catecholamines, also known as broken heart syndrome. Restrictive cardiomyopathy is marked by diastolic dysfunction, often due to amyloidosis, which is Congo red positive with apple-green birefringence. Arrhythmogenic right ventricular cardiomyopathy (ARVC) features fat deposition in the right ventricle and is associated with Naxos syndrome (plaoglobin defect, autosomal dominant), woolly hair, and hyperkeratosis.
Cardiac Tumors: Myxomas and Rhabdomyomas [28:32]
A 50-year-old woman with fatigue, dyspnea, left atrial enlargement, and mitral valve calcification likely has a myxoma. Metastasis is the most common cardiac malignancy. Myxomas (adults, left atria) show lepidic cells and are linked to Carney complex (PRKAR1A mutation). Rhabdomyomas (children, left ventricle) show spider cells and are associated with tuberous sclerosis (TSC1/TSC2 mutations). Name and Lamb syndromes involve skin problems and atrial myxomas.
Vascular Tumors: Glomus Tumors and Angiosarcomas [34:22]
A glomus tumor, arising from a glomus body, is an exquisitely painful subungual tumor. Cystic hygroma, a lymphatic channel tumor (lymphangioma), occurs in the neck and is associated with Turner syndrome (45XO). Angiosarcoma development is linked to VAT chemicals (vinyl chloride, arsenic, thorotrast). Benzene causes AML and bladder cancer, while tobacco is a risk factor for renal cell carcinoma. Kaposi sarcoma, a reddish-purple skin tumor common on the lower legs in HIV patients, is associated with HHV8 and can occur at any CD4 count below 500, typically below 200.
Vasculitis: Takayasu Arteritis and Polyarteritis Nodosa [43:27]
Takayasu arteritis, or pulseless disease, affects individuals under 50, involving the subclavian artery and causing upper limb pulse absence. Giant cell arteritis, affecting those over 50, is a granulomatous temporal arteritis with throbbing headaches and jaw claudication, treated with steroids ASAP to prevent blindness. Polyarteritis nodosa (PAN), a medium vessel vasculitis, spares pulmonary vessels and is associated with hepatitis B (Australia antigen). PAN causes fibronoid necrosis and flea-bitten kidney. Kawasaki disease (kids) features fever, non-purulent conjunctivitis, rash, edema, adenopathy (unilateral cervical), and strawberry tongue; anti-endothelial cell antibodies are involved. Buerger's disease (thromboangiitis obliterans) is linked to smoking and HLA polymorphisms (B5, A9), affecting arteries and veins, causing intermittent pain.
Vasculitis: Henoch-Schönlein Purpura and Wegener's Granulomatosis [59:36]
Henoch-Schönlein purpura (HSP) in kids involves IgA deposition, palpable purpura below the buttocks, abdominal pain, arthralgia, and renal involvement (hematuria). Palpable purpura is seen in HSP, non-palpable purpura in ITP (low platelet count), and pinch purpura in amyloidosis. Wegener's granulomatosis (granulomatosis with polyangiitis) affects lungs and kidneys, showing granulomas and C-ANCA (PR3-ANCA), also involves ears, nose, and throat (ENT triad).
Respiratory Pathology: Asthma and Asbestosis [1:10:23]
Asthma features Charcot-Leyden crystals (galectin-10 from eosinophils), Curschmann spirals (mucin), and Creola bodies in sputum. Asbestosis, linked to shipyard and cement industries, causes pleural plaques, nodules, and tumors (mesothelioma, adenocarcinoma). Asbestos bodies (ferruginous bodies) are dumbbell-shaped fibers covered with iron, stained with Prussian blue.
Lung Tumors: Hamartomas and Carcinomas [1:20:29]
Pulmonary hamartomas show coin lesions and popcorn calcification, composed of native tissue (cartilage). Small cell carcinoma (oat cell cancer) is associated with smoking, synaptophysin marker, and azzopardi effect (blue blood vessels due to tumor cell DNA, confirmed by Fuelgen stain). Small cell lung cancer is aggressive and shows paraneoplastic syndromes like SIADH. Squamous cell carcinoma shows keratin pearls and P40 marker, while adenocarcinoma shows empty glands and napsin A, TTF1, and MUC1 markers.
Lung Cancer and Alpha-1 Antitrypsin Deficiency [1:36:10]
The most common lung malignancy is metastasis. Small cell carcinoma is the most aggressive. Squamous cell carcinoma is associated with hypercalcemia, adenocarcinoma with migratory thrombophlebitis (Trousseau's phenomena), and large cell carcinoma with gynecomastia. Alpha-1 antitrypsin deficiency, linked to the SERPINA gene on chromosome 14, causes panacinar emphysema and cirrhosis, with PAS-positive globules in the liver.
Gastrointestinal Pathology: Glomus Tumors and Angiosarcomas [1:47:17]
A glomus tumor, arising from a glomus body, is an exquisitely painful subungual tumor. Cystic hygroma, a lymphatic channel tumor (lymphangioma), occurs in the neck and is associated with Turner syndrome (45XO). Angiosarcoma development is linked to VAT chemicals (vinyl chloride, arsenic, thorotrast). Benzene causes AML and bladder cancer, while tobacco is a risk factor for renal cell carcinoma. Kaposi sarcoma, a reddish-purple skin tumor common on the lower legs in HIV patients, is associated with HHV8 and can occur at any CD4 count below 500, typically below 200.
Stomach Pathology: Ménétrier's Disease and Gastric Cancer [1:55:18]
Ménétrier's disease features cerebriform rugae, protein loss, and foveolar cell hyperplasia, caused by increased TGF-alpha. Linitis plastica (leather bottle stomach) is diffuse gastric cancer with decreased E-cadherin (CDH1 gene). Signet ring cells (nucleus pushed to the periphery due to mucin) are seen in diffuse gastric cancer and Krukenberg tumors of the ovary.
Intestinal Pathology: Whipple's Disease and Celiac Disease [2:01:14]
Whipple's disease features foamy macrophages filled with PAS-positive granules in the lamina propria, caused by Tropheryma whipplei (Gram-positive bacteria). Celiac disease (gluten sensitivity) involves villous atrophy, crypt hyperplasia, and inflammatory cell infiltrate (CD8+ T lymphocytes), with IgA anti-tTG and anti-endomysial antibodies. Celiac disease is associated with HLA DQ2/DQ8 polymorphisms. Dermatitis herpetiformis (skin manifestation of celiac disease) is treated with dapsone. Untreated celiac disease increases the risk of enteropathy-associated T-cell lymphoma (EATL).
Polyposis Syndromes: Juvenile Polyposis and Peutz-Jeghers Syndrome [2:09:29]
Juvenile polyposis features hamartomatous colon polyps in children, with SMAD4/BMPR1A mutations. Peutz-Jeghers syndrome involves mucosal pigmentation and hamartomatous polyps (Christmas tree appearance) in the jejunum, with STK11/LKB1 mutations. Cowden syndrome features polyps, thyroid cancer (follicular carcinoma), endometrial cancer, breast cancer, and skin tumors (trichilemmoma), with PTEN mutation. Cronkhite-Canada syndrome is non-hereditary, affecting individuals over 50, with hair loss, skin pigmentation, and nail atrophy.
Neuropathology: Huntington's Disease and Alzheimer's Disease [2:16:30]
Huntington's disease features ubiquitin deposition in the caudate nucleus, CAG repeats, and chorea. Alzheimer's disease, the most common cause of dementia, shows neurofibrillary tangles (tau protein) and Hirano bodies (actin). Parkinson's disease involves decreased dopaminergic neurons and Lewy bodies (alpha-synuclein).
Brain Tumors: Schwannomas and Gliomas [2:26:10]
NF2 (neurofibromatosis type 2) features bilateral acoustic schwannomas (cranial nerve VIII), showing ice cream cone appearance, Antoni A and B areas, and Verocay bodies. Pilocytic astrocytoma (childhood tumor) features cystic lesions in the cerebellum, Rosenthal fibers, and BRAF mutation. Glioblastoma (adult tumor) shows serpentine necrosis and IDH wild-type mutation. Oligodendroglioma shows fried egg appearance and codeletion 1p19q. Meningiomas (more common in females) are hormone-dependent, showing whorling of tumor cells and psammoma bodies.
Thyroid Tumors: Papillary and Follicular Carcinomas [2:37:52]
Papillary carcinoma of the thyroid features orphan Annie nuclei (formalin artifact), intranuclear inclusions, and psammoma bodies, with BRAF mutation. Follicular carcinoma of the thyroid cannot be diagnosed on FNAC due to the need to assess capsule and vascular invasion, and it shows RAS gene mutation. Medullary carcinoma of the thyroid is associated with the RET gene (chromosome 10) and MEN 2A/2B, with calcitonin as a tumor marker.
Bonus Slides and Final Thoughts [3:16:43]
The session concludes with a reminder to review bonus slides on ovarian, testicular, and breast tumors. The presenter encourages focusing on high-yield topics and prioritizing rapid revision with thorough understanding.