WBR0479
| Author | [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Yazan Daaboul, M.D.)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Immunology, MainCategory::Pathology |
| Sub Category | SubCategory::Head and Neck |
| Prompt | [[Prompt::A 6-month-old boy is brought to the physician's office for recurrent infections. Following appropriate work-up, the patient is diagnosed with an inherited X-linked disease that causes a defective interleukin (IL)-2 receptor and is a candidate for bone marrow transplantation (BMT). Which of the following findings on physical examination is most likely associated with the patient's condition?]] |
| Answer A | AnswerA::Absent pus formation |
| Answer A Explanation | [[AnswerAExp::Absent pus formation is observed among patients with leukocyte adhesion deficiency (LAD).]] |
| Answer B | AnswerB::Partial albinism |
| Answer B Explanation | [[AnswerBExp::Partial albinism is observed among patients with Chediak-Higashi syndrome.]] |
| Answer C | AnswerC::Retained primary teeth |
| Answer C Explanation | [[AnswerCExp::Retained primary teeth is observed among patients with Job's syndrome (Hyper IgE syndrome).]] |
| Answer D | AnswerD::Absent palatine tonsils |
| Answer D Explanation | [[AnswerDExp::Absent palatine tonsils is observed among patients with Bruton's agammaglobulinemia]] |
| Answer E | AnswerE::Absent thymic shadow on chest xray |
| Answer E Explanation | [[AnswerEExp::Absent thymic shadow is a finding due to thymic hypoplasia, is seen in patients with SCID.]] |
| Right Answer | RightAnswer::E |
| Explanation | [[Explanation::Severe combined immunodeficiency (SCID) is an immunological disease that is commonly inherited by an X-linked pattern. It is characterized by recurrent infections due to deficiency of both B-cells and T-cells. There are several causes of SCID; commonly IL-2 receptor defect and adenosine deaminase deficiency are the culprit.
Because of T-cell deficiency in SCID, patients will have thymic hypoplasia that is manifested as an absent thymic shadow on chest xray. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::thymic, WBRKeyword::hypoplasia, WBRKeyword::thymus, WBRKeyword::SCID, WBRKeyword::severe, WBRKeyword::combined, WBRKeyword::immunodeficiency, WBRKeyword::severe combined immunodeficiency, WBRKeyword::interleukin, WBRKeyword::receptor, WBRKeyword::2, WBRKeyword::adenosine, WBRKeyword::deaminase, WBRKeyword::deficiency, WBRKeyword::absent, WBRKeyword::thymic, WBRKeyword::shadow, WBRKeyword::xray |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |