WBR0835
| Author | PageAuthor::Neeraja Danda M.B.B.S |
|---|---|
| Exam Type | ExamType::USMLE Step 2 CK |
| Main Category | MainCategory::Internal medicine |
| Sub Category | SubCategory::Cardiovascular, SubCategory::Musculoskeletal/Rheumatology |
| Prompt | [[Prompt::A 38-year-old female presents to the office with complaints of intermittent chest pain for the last 3 months. The pain is severe while lying down and subsides upon sitting. She also complains of on and off knee pain. Vitals signs include blood pressure 120/70, respiratory rate 20/minute and pulse rate 78 bpm. On physical examination there is a purplish rash on face. Electrocardiogram shows diffuse ST segment elevation. What is the most specific test to diagnose the underlying cause of this chest pain?]] |
| Answer A | AnswerA::Anti nuclear antibodies(ANA) |
| Answer A Explanation | AnswerAExp::'''Incorrect''' ANA is the most sensitive test for Systemic lupus erythematosus, but not the most specific. |
| Answer B | AnswerB::Anti SSA, Anti SSB antibodies |
| Answer B Explanation | AnswerBExp::'''Incorrect'''Anti SSA and Anti SSB are seen in Systemic lupus erythematosus but they are also present in Sjogrens syndrome. |
| Answer C | AnswerC::Complement levels |
| Answer C Explanation | AnswerCExp::'''Incorrect''' Decreased compliment levels indicate a disease flare-up in Systemic lupus erythematosus, increased compliment levels are not informative for SLE. |
| Answer D | AnswerD::Anti ds-DNA antibodies |
| Answer D Explanation | AnswerDExp::The most specific test to diagnose Systemic lupus erythematosus is Anti ds-DNA antibodies. |
| Answer E | AnswerE::Cardiac Enzyme levels |
| Answer E Explanation | AnswerEExp::'''Incorrect''' Electrocardiogram findings and chest pain changing with position suggests Pericarditis more than myocardial Infarction. |
| Right Answer | RightAnswer::D |
| Explanation | [[Explanation::A 38-year-old female with a facial rash, joint pain and chest pain that changes with position suggests connective tissue disease induced pericarditis. The most common connective tissue disease causing pericarditis is Systemic lupus erythematosus (SLE). Electrocardiogram findings of diffuse ST segment elevation also points towards pericarditis. The most specific test to diagnose Systemic lupus erythematosus is Anti ds-DNA antibodies.
Educational Objective: Anti ds-DNA is the most specific test for Systemic lupus erythematosus. Systemic lupus erythematosus is the most common connective tissue disease cause of Pericarditis. References: Page 183 Master the boards Step 2 CK second edition |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Systemic Lupus Erythematosus, WBRKeyword::Anti ds DNA |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |