WBR0471

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Author [[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Alison Leibowitz)]]
Exam Type ExamType::USMLE Step 1
Main Category MainCategory::Pathology
Sub Category SubCategory::Hematology
Prompt [[Prompt::A 12-year-old African male, with a history of beta-thalassemia major, is brought to the physician's office for a routine bone marrow transplantation (BMT) work-up. Prior to BMT, liver biopsy is performed to calculate Pesaro class risk for the patient. Which of the following findings is most likely observed upon liver biopsy?]]
Answer A AnswerA::Hepatocyte accumulation of copper
Answer A Explanation [[AnswerAExp::The accumulation of cupper frequently occurs in Wilson's disease.]]
Answer B AnswerB::Hepatocyte accumulation of iron
Answer B Explanation AnswerBExp::The accumulation of iron frequently occurs following recurrent transfusions, administered to patients with thalassemia major or hemochromatosis.
Answer C AnswerC::Hepatocyte accumulation of lead
Answer C Explanation AnswerCExp::Lead does not frequently accumulate in the livers of individuals with thalassemia major.
Answer D AnswerD::Hepatocyte accumulation of calcium
Answer D Explanation AnswerDExp::Thalassemia major is not associated with calcium accumulation.
Answer E AnswerE::Hepatocyte accumulation of lipids
Answer E Explanation [[AnswerEExp::Hepatic steatosis, or accumulation of lipids in the liver, is associated with chronic alcoholism.]]
Right Answer RightAnswer::B
Explanation [[Explanation::Beta-thalassemia major, an inherited hematological disorder, is characterized by the reduced (or absent) production of a beta-globin chain of hemoglobin proteins, resulting from a point mutation in splice sites or promoter sequences. It manifests as severe anemia, and subsequent ineffective erythropoiesis, which eventually cause bone marrow expansion.

Cases of Beta-thalassemia major are often reported in the Mediterranean region, Africa, and Southeast Asia.

In individuals with beta-thalassemia major, chronic red cell transfusions are considered the optimal therapy for relieving symptoms. Repeated transfusions are associated with iron overload, requiring the administration of iron-chelating therapy, frequently with deferoxamine.

Bone marrow transplant is considered the only cure for patients with beta-thalassemia major. Pesaro classification, a detailed pre-BMT evaluation often used to predict outcomes following transplant, evaluates three independent risk factors: Hepatomegaly on physical examination, portal fibrosis on liver biopsy, and adequacy of iron chelation.
Educational Objective: Beta-thalassemia major, a hematological inherited disorder, is characterized by the absent or reduced production of beta-chains of hemoglobin proteins. Recurrent red cell transfusions, a symptomatic treatment, are associated with iron accumulation, which necessitates the administration of iron-chelation therapy.
References: Lucarelli G, Galimberti M, Polchi P, et al. Marrow transplantation in patients with thalassemia responsive to iron chelation therapy. N Eng J Med. 1993;329:840-4.]]

Approved Approved::Yes
Keyword WBRKeyword::Beta-thalassemia, WBRKeyword::Mediterranean, WBRKeyword::inherited, WBRKeyword::Liver, WBRKeyword::Hepatocyte, WBRKeyword::Iron accumulation, WBRKeyword::Deferoxamine, WBRKeyword::Bone marrow transplant, WBRKeyword::Pesaro, WBRKeyword::Transfusions, WBRKeyword::BMT
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