WBR0422
Jump to navigation
Jump to search
| Author | [[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Yazan Daaboul, M.D. and Alison Leibowitz [1])]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Biochemistry |
| Sub Category | SubCategory::Hematology |
| Prompt | [[Prompt::A 6-month-old boy is brought by his mother to the pediatrician's office for evaluation. The mother explains that she recently palpated an abdominal mass while showering her child and has been concerned about his health. In the clinic, physical examination is remarkable for hepatosplenomegaly. The patient then undergoes further work-up, and bone marrow biopsy demonstrates lipid-engorged macrophages under light microscopy upon staining with periodic acid-Schiff (PAS) reagent. Lab work-up in this patient is remarkable for elevated concentration of which of the following compounds?]] |
| Answer A | AnswerA::Ceramide trihexoside |
| Answer A Explanation | [[AnswerAExp::Ceramide trihexoside accumulation is characteristic of Fabry’s disease.]] |
| 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 is an autosomal recessive lyososomal storage disease caused by mutations in the GBA gene. It is characterized by the deficiency of glucocerebrosidase (glucosylceramidase) enzyme activity in peripheral leukocytes and accumulation of glucocerebrosides. The clinical manifestations of Gaucher disease range from an asymptomatic clinical course to fatal outcomes. Gaucher disease typically manifests with bone disease (type 1), neurological symptoms (types 2 and 3), hematological disorders (hepatosplenomegaly, thrombocytopenia, and anemia), and aseptic necrosis of the femur. Patients may also complain of bone and joint pain crises, especially in the hips and knees. On bone marrow biopsy, Gaucher disease shows characteristic Gaucher cells, which are lipid-engorged macrophages that resemble crumpled tissue paper under light microscopy upon staining with periodic acid-Schiff (PAS) reagent. Optimal management of Gaucher disease includes enzyme replacement therapy or substrate reduction therapy. Symptomatic management includes splenectomy, blood transfusions, and analgesia for chronic bone pains. Educational Objective: Gaucher disease is an autosomal recessive lyososomal storage disease characterized by deficiency of glucocerebrosidase and accumulation of glucocerebrosides. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Gaucher disease, WBRKeyword::Lyosomal storage disease, WBRKeyword::Glucocerebroside, WBRKeyword::Hepatosplenomegaly, WBRKeyword::Inheritance, WBRKeyword::Autosomal recessive, WBRKeyword::Accumulation, WBRKeyword::Crumpled tissue paper, WBRKeyword::Macrophages |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |