WBR0275
| Author | [[PageAuthor::Ogheneochuko Ajari, MB.BS, MS [1] (Reviewed by Alison Leibowitz)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pathology |
| Sub Category | SubCategory::Pulmonology, SubCategory::General Principles |
| Prompt | [[Prompt::A 36-year-old male presents to the physician’s office complaining of night sweats, chest pain, weight loss, and a 2-month history of coughing that has not responded to cough expectorants. He recently moved back to the United States from West Africa, where he lived in a densely populated city for about 5 years. A physical examination, chest X ray, and Sputum AFB confirm Mycobacterium tuberculosis. Which of the following types of necrosis would you likely find in this condition?]] |
| Answer A | AnswerA::Caseous necrosis |
| Answer A Explanation | AnswerAExp::See explanation |
| Answer B | AnswerB::Coagulation necrosis |
| Answer B Explanation | [[AnswerBExp::Coagulation necrosis involves the denaturation of enzymes and structural proteins, and microscopically, indistinct outlines of cells that are observed within dead tissues. This type of necrosis occurs mostly in the heart, liver, and kidneys.]] |
| Answer C | AnswerC::Liquefactive necrosis |
| Answer C Explanation | [[AnswerCExp::Liquefactive necrosis is often observed in the brain from the autocatalytic effect of hydrolytic/lysosomal enzymes released by neutrophils or necrotic cells. Liquefactive necrosis occurs in the CNS, most frequently in localized bacterial infections (abscesses).]] |
| Answer D | AnswerD::Fat necrosis |
| Answer D Explanation | [[AnswerDExp::Fat necrosis occurs in fatty tissue, such as the breast tissue, as a result of trauma or adipose tissue, seen in an acutely inflamed pancreas.]] |
| Answer E | AnswerE::Fibrinoid necrosis |
| Answer E Explanation | [[AnswerEExp::Fibrinoid necrosis frequently occurs in blood vessels such as small arteries, arterioles, venules, and glomerular capillaries.]] |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::Caseous necrosis is a form of necrosis in which caseous material is formed by the release of lipid from the cell walls exhibited by Mycobacterium tuberculosis and systemic fungi such as Histoplasma capsulatum, Coccidioides immitis and Blastomyces dermatitidis. It is associated with acellular, cheese-like material in the center of a granuloma which contains activated macrophages, CD4 helper T cells and multinucleated giant cells. Educational Objective: Caseous necrosis is a type of necrosis formed by the release of lipid from the cell walls of Mycobacterium tuberculosis and systemic fungi with an associated acellular cheese-like material in the center of a granuloma containing macrophages, CD4 helper T cells, and multinucleated giant cells. |
| Approved | Approved::Yes |
| Keyword | |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |