Pathology videos & books

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Correct Answer - D Ans: D. Endothelial injury The three primary abnormalities that lead to thrombus formation (called Virchow's triad) are (1) endothelial injury, (2) stasis or turbulent blood flow, and (3) hypercoagulability of the blood.

Correct Answer - C Ans: C. 30% of people have HbsAg positive Polyarteritis nodosa (PAN) is a necrotizing vasculitis involving small and medium-sized muscular arteries of multiple organs and tissues. The disease occurs more commonly in adult males than females. Most commonly affected organs, in descending order of frequency of involvement, are the kidneys, heart, gastrointestinal tract, kidneys, and muscle. The condition results from immunologic response to an identifiable antigen that may be bacteria (e.g. streptococci, staphylococci, mycobacteria), viruses (e.g. hepatitis B virus, influenza virus, CMV), malarial parasite, certain drugs, and chemicals. There is no association with ANCA, [7] but about 30% of people with PAN have chronic hepatitis B and deposits containing HBsAg- HBsAb complexes in affected blood vessels, indicating an immune complex-mediated cause in that subset. Infection with the Hepatitis C virus and HIV are occasionally discovered in people affected by PAN. Leukocytoclastic vasculitis, characterized by fibrinoid necrosis with neutrophilic infiltrate in the vessel wall. Many of the neutrophils are fragmented. This form is found in vasculitis caused by deposits of immune complexes.

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Correct Answer - A Ans: A. Lead poisoning Findings Microcytic Anemia - Iron Deficiency Hypersegmented Neutrophils - B12 and Folic Acid Deficiency Young & No H/o Of Alcohol Consumption [Patient came with a history of Fatigue and Tiredness] - Chronic Alcoholism can be ruled out Hemolytic Anemia - may demonstrate red blood cell fragments called schistocytes, red blood cells that look like spheres (spherocytes), and/or red blood cells missing small pieces (bite cells). An increased number of newly made red blood cells (reticulocytes) may also be a sign of bone marrow compensation for anemia.

Correct Answer - D Ans: D. Unidirectional locomotion of neutrophils Chemotaxis is defined as a unidirectional movement of leukocytes up to a concentration gradient of chemotactic molecules. All granulocytes, monocytes and to a lesser extent lymphocytes respond to chemotactic stimuli with varying rates of speed. Chemoattractants are exogenous or endogenous. Exogenous agents are bacterial products. Endogenous mediators are: Components of complement pathway C5a Products of lipoxygenase pathway LTB4 Cytokines particularly those of chemokine families.

Correct Answer - A Answer- A- Immunochromatography assays HBV chronic carriers are those in whom HBsAg persists for more than 6 months in the presence of HBeAg or anti-HBe. HBsAg may persist for years after the loss of HBeAg. The most useful detection methods are enzyme-linked Immunosorbent assay for HBV antigens and antibodies and PCR for viral DNA -Jawetz 27/e pg- 504 Serological assays detect the host immune response (antibodies to HCV) or a viral antigen (HBsAg, HCVcAg). They are based on the immunoassay principle and are available in the form of rapid diagnostic tests (RDTs) or laboratory-based enzyme immunoassays (EIAs), chemiluminescence immunoassays (CLIAs) and electrochemiluminescence immunoassays (ECLs).

Correct Answer - D Ans. is 'd' i.e., None The morphologic consequences of embolic occlusion of the pulmonary arteries depend on the size of the embolic mass and the general state of the circulation. Large emboli may impact in the main pulmonary artery or its major branches or lodge at the bifurcation as a saddle embolus. Sudden death often ensues, owing largely to the blockage of blood flow through the lungs. Death may also be caused by acute failure of the right side of the heart (acute cor pulmonale). Smaller emboli can travel out into the more peripheral vessels, where they may cause infarction. In patients with adequate cardiovascular function, the bronchial arterial supply can often sustain the lung parenchyma despite obstruction to the pulmonary arterial system. Under these circumstances, hemorrhages may occur, but there is no infarction of the underlying lung parenchyma. Only about 10% of emboli actually cause infarction. Although the underlying pulmonary architecture may be obscured by the suffusion of blood, hemorrhages are distinguished by the preservation of the pulmonary alveolar architecture; in such cases, resorption of the blood permits reconstitution of the preexisting architecture.

Correct Answer - B Ans. is 'b' i.e., Dermatomyositis Dermatomyositis is a connective-tissue disease related to polymyositis that is characterized by inflammation of the muscles and the skin. It is a systemic disorder that may also affect the joints, the esophagus, the lungs, and, less commonly, the heart. On the muscle biopsy, there are two classic microscopic findings of dermatomyositis. They are : mixed B- & T-cell perivascular inflammatory infiltrate and perifascicular muscle fiber atrophy. It is associated with autoantibodies, especially anti-Jol antibody

Correct Answer - D Ans. is 'd' i.e., Seen in teratoma o Psammoma bodies represent a process of dystrophic calcification. o Single necrotic cells may constitute seed crystals that become encrusted by the mineral deposits. The progressive acquisition of outer layers may create lamellated configurations, called psammoma bodies because of their resemblance to grains of sand. o Psammoma bodies are seen in : papillary cancer of thyroid, meningioma, papillary serous cystadenocarcinoma of ovary.