UWorld_2.27 Flashcards Preview

USMLE Step 1 > UWorld_2.27 > Flashcards

Flashcards in UWorld_2.27 Deck (20)
1

Fabry disease: inheritance, deficient enzyme, accumulated metabolite, presentation

  • X-linked
  • alpha-galactosidase
  • ceramide trihexoside
  • sx
    • angiokeratomas
    • cardiac and renal involvement
    • painful neuropathy

2

Gaucher disease: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • B-glucocerebrosidase
  • glucocerebroside
  • sx
    • gaucher cells = "tissue paper" macs 
    • hepatosplenomegaly
    • developmental delay

3

Hurler syndrome: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • a-L-iduronidase
  • dermatan & heparan sulfate
  • Sx
    • gargoylism
    • corneal clouding 
    • hepatosplenomegaly
    • devolpmental delay

4

Hunter syndrome: inheritance, deficient enzyme, accumulated metabolite, presentation

  • X-linked recessive
  • iduronidate sulfatase
  • dermatan & heparan sulfate
  • Sx
    • milder hurler syndrome
    • gargoylism
    • NO corneal clouding 
    • hepatosplenomegaly
    • devolpmental delay

5

Niemann-Pick Disease: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • sphingomyelinase
  • sphingomyelin
  • sx
    • hepatosplenomegaly
    • cherry-red macula spot
    • foam cells (lipid-laden macs)
    • progressive neurodegeneration

6

Tay-Sachs Disease: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • B-hexosaminidase A
  • GM2 ganglioside
  • sx
    • NO hepatosplenomegaly
    • cherry-red macula spot
    • progressive neurodegeneration

7

Krabbe Disease: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • galactocerebrosidase
  • galactosylsphingosine & galactocerebroside
  • Sx
    • progressive neurodegeneration
    • optic atrophy

8

Metachromic leukodystrophy: inheritance, deficient enzyme, accumulated metabolite, presentation

  • AR
  • arylsulfatase A
  • cerebroside sulfate
  • sx
    • muscle wasting
    • dementia
    • ataxia

9

Pathways ==> lysosomal storage disease

10

Characteristics of mucormycosis

  • opportunistic infection caused by Rhizopus, Mucor, and Absidia species
  • ==> paranasl sinus involvement in a diabetic or immunosuppressed patient
    • facial or periorbital pain
    • H/A
    • purulent nasal discharge
    • black eschar (necrotic tissue) may be seen @ palate or nasal turbinates
  • fungi form broad, nonseptate hyphae that branch at right angles

11

Candida albicans presentation

  • ==> variety of sx in immunosuppressed patients
  • ==> R-sided endocarditis, renal abscesses, pneumonia, esophagitis
  • budding yeasts and pseudohyphae

12

Characteristics of aspergillosis

  • can involve paranasal sinuses, lungs, etc.
  • light microscopy ==> septate hyphae that branch @ 45 degree angle

13

Dobutamine impact on pressure-volume loop

  • ==> increased contractility
  • ==> higher pressures during ventricular ejection phase + greater volume expelled
  • ==> widening of P-V loop

14

Gastric secretions

  • epithelial layer ==> mucous for protection
  • upper glandular layer = parietal cells @ body & fundus ==> gastric acid + intrinsic factor
  • deep gastric glands = chief cells ==> pepsinogen

15

Characteristics of MG

  • autoimmune type II, antibody-mediated, hypersensitivy rxn against skeletal myocyte surface acetylcholine receptors
  • improves with edrophonium (tensilon) injection = anti-cholinesterase agent

16

Immune sensitivity types:

  • Hypersensitivity pneumonitis 
  • Goodpasture
  • Sarcoidosis
  • PSGN
  • Contact dermatitis
  • Atopic dermatitis

  • HP = type III
  • Goodpasture = type II
  • Sarcoidosis = type IV
  • PSGN = type III
  • Contact derm = type IV
  • atopic = eczema = can involve type I

17

Conus medullaris syndrome presentation

  • lesions @ L2
  • ==> flaccid paralysis of bladder and rectum
    • impotence
  • ==> saddle (S3-S5 roots) anesthesia
  • ==> mild weakness of leg m. if adjecent cord/nerves spared
  • common causes
    • disk herniation
    • tumors
    • spinal fractures

18

Cauda equina syndrome presentation

  • massive rupture of intervertebral disk ==> compression of 2+/18 nerve root w/in cauda equina
  • sx
    • low back pain radiating to legs
    • saddle anesthesia
    • loss of anocutaneous reflex
    • bowel/bladder dysfxn (S3-S5)
    • loss of ankle-jerk + plantar flexion weakness

19

Emphysema consequences on PFTs

  • destruction of interalveolar walls + decreased elastic recoil ==>
  • FVC = normal to low
  • Forced expiratory = low
  • FEV1/FVC = low
  • Total lung capacity = increased
  • Fxnl residual capacity = increased ++
  • pulm. compliance = increased
  • bronchodilator response = none
  • DLCO = low

20

Chronic bronchitis consequences on PFTs

  • destruction of interalveolar walls + decreased elastic recoil ==>
  • FVC = normal to low
  • Forced expiratory = low
  • FEV1/FVC = low
  • Total lung capacity = normal
  • Fxnl residual capacity = increased +
  • pulm. compliance = normal
  • bronchodilator response = partial response
  • DLCO = normal

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