High Yield Syndromes

Question 1

NF1 (Von Recklinghausen disease)

Answer 1

Cafe au lait, skin neurofibromas, lisch nodules (pigmented hamartomas of the iris), and optic nerve gliomas
NF1 on chr 17

Question 2

NF2

Answer 2

Bilateral acoustic schwannomas, multiple meningiomas

NF2 on chr 22

Question 3

Sturge-Weber syndrome

Answer 3

CNV1 port-wine stain + ipsilateral leptomeningeal angioma (seizures, calcification of underlying gyri = "tram-track" on Xray), episcleral hemangioma (glaucoma), and intellectual disability (affects underlying brain tissue)
GNAQ gene (activating mutation, NOT inherited)

Question 4

Von Hippel-Lindau disease

Answer 4

Hemangiomas in retina/cerebellum, cysts/neoplasms in kidney/liver/pancreas, bilateral renal cell CA
VHL gene on chr 3 (autosomal dominant)

Question 5

Osler-Weber-Rendu syndrome (hereditary hemorrhagic teleangectasia)

Answer 5

Telangectasias (recurrent epistaxis, GI bleeds, hematuria) and anterior-venous malformations

Question 6

Tuberous Sclerosis

Answer 6

Ash-leaf spots, shagreen patches, facial angiofibromas, mental retardation, seizures, astrocytoma, renal angiomyolipoma, and cardiac rhabdomyoma
Classic triad = facial angiofibromas + seizures + intellectual disability
TSC1 (hamartin) and TSC2 (tuberin) - autosomal dominant

Question 7

Friedrich ataxia

Answer 7

Ataxia/nystagmus, weakness, loss of proprioception/vibration, dysarthria, pes cavus, hammer toes, hypertrophic cardiomyopathy
Autosomal recessive GAA trinucleotide repeat on chr 9 that impairs frataxin gene (Fe accumulates in mito which damages neurons)

Question 8

Hartnup disease

Answer 8

Defect in neutral AA/Na transporters of the proximal tubule

= neutral aminoaciduria + pellagra

Question 9

Fanconi syndrome

Answer 9

Impaired reabsorption of all AAs, glucose, bicarb, and PO4

= aminoaciduria (including Pro and Arg not seen in Hartnup) + metabolic acidosis (proximal tubular acidosis)

Question 10

Klinefelter syndrome

Answer 10

Tall, testicular atrophy, female body shape, gynecomastia, and infertility (abnormal testes = high FSH/LH and estrogen)
47XXY

Question 11

Turner syndrome

Answer 11

Short, streak ovaries (high FSH/LH and low estrogen), shield chest, cystic hygroma (lymph defects), horseshoe kidney, preductal aortic coarctation, bicuspid aortic valve
45XO