Collagen and Elastin Disorders Flashcards
what is osteogenesis imperfecta
mutation:
inheritence:
manifestations:
this is brittle bone disorder
mutation: COLA1 and COLA2
inheritance: autosomal dominant; loss of type 1 collagen: issue in the glycosylation step: no triple helix
manifestations: multiple fractures after minimal trauma, blue sclera, tooth abnormalities (opalescent teeth- lack of dentin), conductive hearing loss.
osteogenesis imperfecta can be confused with?
child abuse
mnemonic for osteogenesiss imperfecta: Patients cant BITE
Bones= fractures
I (eye) = blue sclera
Teeth= dental imperfections
Ear= hearing loss
what ehlers danlos syndrome
inheritance:
mutations:
faulty collagen synthesis causing hyperextensible skin, hypermobile joints, and tendency to bleed
inheritance: autosomal dominant or autosomal recessive
mutations: classical- COLA5 vascular type: COLA3
ehlers danlos syndrome may be associated with
berry aneurysms, aortic aneurysms, joint dislocation, organ rupture
what is menkes disease
mutation:
inheritance:
manifestations:
connective tissue disease caused by impaired copper absorption; decreased lysl oxidase and collagen cross-linking
mutation: ATP7A (absent)
inheritance: x-linked
manifestations: kinky hair, growth/developmental delay, cerebral aneurysms, hypotonia
what is elastin?
a stretchy protein in skin, lungs, arteries, ligaments, vocal cord, epiglotis, and ligamentum flava
elastin is rich in?
nonhydorxylated proline, glycine, and lysine
elastin is crosslinked by lysl oxidase and broken down by elastase which is inhibited by?
a1 anti-trypsin
def causes COPD
marfan syndrome
inheritance:
mutation:
manifestations:
connective tissue disorder affecting skeleton, heart, and eyes: defective fibrilin-I that normally sequesters TGFB
mutation: FBN1 (marFan) on chromosome 15
inheritance: autosomal dominant
manifestations: pectus excavatum, tall, long extremities, hypermobile joints, long tapering fingers, cystic medial necrosis of the aorta, aortic aneurysm/rupture/DISSECTION, MVP, spontenous pneumothorax, lens dislocation
Homocystinuria
mutation:
inheritance:
manifestations:
homosystine buildup; similar presentation to marfans syndrome
mutation: cystathionine synthase def
manifestations: scoliosis, decreased intellect, thromosis , nasal lens dislocation, tall, joint hyperlaxity,
inheritance: autosomal recessive
eye dislocation in marfan
fans out: temporal
