WBR0422
| Author | [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Alison Leibowitz)]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Biochemistry |
| Sub Category | SubCategory::Hematology |
| Prompt | [[Prompt::A mother brings her 6-month-old male to the pediatrician's office for evaluation, concerned by an abdominal mass she palpated while showering her child. Upon physical examination, you note hepatosplenomegaly. A bone marrow biopsy reveals the finding illustrated in the image below. Lab work-up will most likely reveal an elevated level of which of the following compounds?
|
| Answer A | AnswerA::Ceramide trihexoside |
| Answer A Explanation | [[AnswerAExp::Ceramide trihexoside accumulation is characteristic of Fabry’s disease. Fabry’s disease and Hunter’s syndrome are X-linked recessive, while other lyososomal storage disease are frequently autosomal recessive. (Mnemonic: FABulous HUNTER is X-Rated)]] |
| Answer B | AnswerB::Glucocerebroside |
| Answer B Explanation | [[AnswerBExp::Glucocerebroside accumulation is characteristic of Gaucher disease.]] |
| Answer C | AnswerC::Sphingomyelin |
| Answer C Explanation | [[AnswerCExp::Sphingomyelin accumulation is characteristic of Niemann-Pick disease.]] |
| Answer D | AnswerD::Galactocerebroside |
| Answer D Explanation | [[AnswerDExp::Galactocerebroside accumulation is characteristic of Krabbe’s disease.]] |
| Answer E | AnswerE::GM2 ganglioside |
| Answer E Explanation | [[AnswerEExp::GM2-ganglioside accumulation is characteristic of Tay-Sachs disease.]] |
| Right Answer | RightAnswer::B |
| Explanation | [[Explanation::Gaucher disease, an autosomal recessive lyososomal storage disease, is characterized by a deficiency of glucocerebrosidase and accumulation of glucocerebrosides. Patients with Gaucher disease frequently display neurological symptoms, hepatosplenomegaly, and aseptic necrosis of the femur. Patients often complain of bone and joint pain crises, especially in the hips and knees.
Gaucher disease is diagnosed upon bone marrow biopsy, which reveals characteristic Gaucher cells, macrophages that resembling crumpled tissue paper under light microscopy. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Gaucher disease, WBRKeyword::lyosomal storage disease, WBRKeyword::glucocerebroside, WBRKeyword::hepatosplenomegaly, WBRKeyword::genetics, WBRKeyword::inheritance, WBRKeyword::autosomal recessive, WBRKeyword::accumulation |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |
