Genetic Disorders Flashcards
what demographic is most affected by acute intermittent porphyria?
women in teens or 20s
what are the diagnostic indicators of acute intermittent porphyria?
- unexplained abdominal crisis
- acute PNS or CNS dysfunction
- recurrent psychiatric illness
- profound hyponatremia
- porphobilinogen in urine (gets dark after standing)
how can AIP be treated?
- avoid drugs that trigger attacks
- high carbohydrate diet
- analgesics for acute episodes
- hematin for elecrolyte imbalance (4 mg/kg up to two times daily)
what enzyme deficiency causes alkaptonuria?
homogentisic acid oxidase
what the diagnostic indicators of alkaptonuria?
- arthropathy
- ochronosis (graying of CT)
- radiodense IV discs
- urine turns black on standing
how is alkaptonuria treated?
in the same way as other arthropathies
when is down syndrome diagnoses?
at birth
what are diagnostic indicators of down syndrome?
- craniofacial abnormalities
- hypotonia
- single palmar crease
what are the main problems that are associated with down syndrome?
- duodenal atresia
- congential heart dz (AV canal defect)
- hematologic malignancy
why do they test the genes of down syndrome babies?
evaluate the risk of future down syndrome babies for that parent
how does fragile X mental retardation affect males?
mental retardation
autism
large testes after puberty
large ears
prominent jaw
high-pitched voice
how does fragile X mental retardation affect females?
learning disabilities
mental retardation
premature ovarian failure
what gene is affected in fragile X mental retardation?
FMR1 gene (expanded trinucleotide repeat)
when should you test for fragile X genetic repeat?
any unexplained mental retardation (2nd common cause after Down syndrome)
what is a possible cause of unexplained tremor/ataxia in middle age?
FMR1 repeat (fragile X tremor-ataxia syndrome)
what are the diagnostic indicators of Gaucher disease?
- anemia
- thrombocytopenia
- hypersplenism
- pathologic fractures
- deficiency of beta glucocerebrosidase
what demographic is commonly affected by Gaucher disease?
Jewish or Easter Europeans
what are Gaucher cells?
phagocytic cells that have a lot of sphingolipid
what is the infantile onset form of Gaucher disease?
type II with neurological problems and poor prognosis
what lab findings would indicate Gaucher disease?
- bone aspirates revealing periodic acid Schiff and eccentric nucleus
- elevated serum acid phosphotase
- deficient glucocerebrosidase
what is the treatment for Gaucher disease?
enzyme replacement (expensive)
what is pleiotropic effect?
autosomal dominant traits that affect several organ systems
what is consanguineous?
parents of an offspring are related to one another
