WBR0437

Author	[[PageAuthor::Yazan Daaboul, M.D. (Reviewed by Alison Leibowitz) (Reviewed by Serge Korjian)]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Genetics
Sub Category	SubCategory::Neurology
Prompt	[[Prompt::A 2-year-old boy is brought by his mother to the physician’s office for seizures. The mother describes that the her son has been developing "unusually" when compared to his siblings. Work-up reveals cortical and retinal hamartomas, renal angiomyolipoma, astrocytoma, and cardiac rhabdomyoma. Which of the following additional findings will most likely be present in this patient?]]
Answer A	AnswerA::Fitzpatrick patches (Ash-leaf spots)
Answer A Explanation	AnswerAExp::See explanation.
Answer B	AnswerB::Oral ganglioneuromas
Answer B Explanation	AnswerBExp::Oral neurogangliomas are frequently observed in MEN2B syndrome, which results from a mutation of the ret oncogene.
Answer C	AnswerC::Retinal hemangioblastoma
Answer C Explanation	[[AnswerCExp::Renal hemangioblastoma is frequently observed in von Hippel-Lindau disease, which results from a deletion of the VHL gene on chromosome 3.]]
Answer D	AnswerD::Bilateral acoustic schwannomas
Answer D Explanation	[[AnswerDExp::Bilateral acoustic schwannomas are frequently observed in neurofibromatosis type II. The NF2 gene is located on chromosome 22.]]
Answer E	AnswerE::Cystic medial necrosis of the aorta
Answer E Explanation	[[AnswerEExp::Cystic medial necrosis of the aorta is frequently observed in patients with Marfan syndrome, a mutation of the FBN1 gene that encodes fibrillin.]]
Right Answer	RightAnswer::A
Explanation	[[Explanation::Tuberous sclerosis is an autosomal dominant inherited disorder frequently characterized by seizures, mental retardation, facial adenoma sebaceum, ash-leaf spots on skin, cortical and retinal hamartomas, renal cysts, angiomyolipomas, cardiac rhabdomyoma, and astrocytoma. The disease has a variable presentation and incomplete penetrance. Educational Objective: Tuberous sclerosis is an autosomal dominant inherited disorder frequently characterized by seizures, mental retardation, facial adenoma sebaceum, ash-leaf spots on skin, cortical and retinal hamartomas, renal cysts, angiomyolipomas, cardiac rhabdomyoma, and astrocytoma. References: Crino PB, Nathanson KL, Henske EP. The tuberous sclerosis complex. N Engl J Med. 2006;355(13):1345-56.]]
Approved	Approved::Yes
Keyword	WBRKeyword::Tuberous sclerosis, WBRKeyword::Hamartoma, WBRKeyword::Angiomyolipoma, WBRKeyword::Rhabdomyoma, WBRKeyword::Astrocytoma
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::