WBR0734
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Immunology |
| Sub Category | SubCategory::Endocrine |
| Prompt | [[Prompt::An 18 year old female patient presents to the physician's office for fatigue. She explains that she has recently been unable to continue daily chores and feels unmotivated all the time. She has also recently gained weight despite normal appetite and complains of recent hair loss. On physical examination, the physician notes a thyroid mass. Following appropriate work-up, the diagnosis of hypothyroidism is made. The patient's thyroid condition is best characterized on histopathological analysis by the presence of lymphocytic infiltrates with germinal centers and presence of large well-defined epithelial cells with eosinophilic granular cytoplasm. Which other disease is associated with the same HLA subtype as that responsible for the patient's condition?]] |
| Answer A | AnswerA::Pernicious anemia |
| Answer A Explanation | AnswerAExp::Similar to Hashimoto's thyroiditis, pernicious anemia, an autoimmune disease that causes vitamin B12 deficiency, is also associated with DR5 HLA subtype. |
| Answer B | AnswerB::Hay fever |
| Answer B Explanation | AnswerBExp::Hay fever is associated with HLA DR2 subtype, along with multiple sclerosis, systemic lupus erythematosus, and Goodpasture's syndrome. |
| Answer C | AnswerC::Rheumatoid arthritis |
| Answer C Explanation | AnswerCExp::Rheumatoid arthritis is associated with HLA DR4 subtype, along with diabetes mellitus type 1. |
| Answer D | AnswerD::Graves' disease |
| Answer D Explanation | AnswerDExp::Graves' disease is associated with HLA DR3 subtype, along with diabetes mellitus type 1. |
| Answer E | AnswerE::Celiac disease |
| Answer E Explanation | AnswerEExp::Celiac disease is associated with HLA DQ2/DQ8 subtypes. |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::The patient has Hashimoto's thyroiditis, an autoimmune thyroid disease that causes hypothyroidism. It is characterized on histopathological analysis by the finding of lymphocytic infiltrates with germinal centers and presence of Hurthle cells. The latter is described as large well-defined epithelial cells with eosinophilic granular cytoplasm.
The patient has typical features of hypothyroidism, including fatigue, weight gain, and hair loss. Hashimoto's thyroiditis is associated with HLA DR5 subtype, similar to pernicious anemia, another autoimmune disease that causes vitamin B12 deficiency due to the presence of auto-antibodies against gastric parietal cells. Educational Objective:
Hashimoto's thyroiditis and pernicious anemia are both associated with HLA DR5 subtype. |
| Approved | Approved::No |
| Keyword | WBRKeyword::pernicious, WBRKeyword::anemia, WBRKeyword::vitamin, WBRKeyword::b12, WBRKeyword::hashimoto, WBRKeyword::hashimoto's, WBRKeyword::Hashimoto, WBRKeyword::Hashimoto's, WBRKeyword::thyroiditis, WBRKeyword::hypothyroidism, WBRKeyword::hair, WBRKeyword::loss, WBRKeyword::weight, WBRKeyword::gain, WBRKeyword::fatigue, WBRKeyword::autoimmune, WBRKeyword::HLA, WBRKeyword::subtype, WBRKeyword::DR5 |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |