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Flashcards in UWorld_2.11 Deck (17)
1

Botulism mechanism of infection

  • main kinds: food-borne, wound, infant (honey)
  • food-borne:
    • spores grow intracellularly
    • autolysis ==> release of neurotoxin into food (NOT actively secreted)
      • toxin can be destroyed by heating, but if food is not cooked well, toxin will exert its effects
    • neurotoxin ==> blocking of ACh release from nerve terminals @ NMJ ==> flaccid paralysis

2

Clinical presenation of botulism

  • "three 'Ds'":
  • diplopia
  • dysphagia
  • dysphonia

3

Characteristics of Digeorge Syndrome

  • CATCH-22
  • Cardiac abnormality (especially tetralogy of Fallot)
  • Abnormal facies
  • Thymic aplasia ==> T-cell dysfxn
  • Cleft palate
  • Hypocalcemia/Hypoparathyroidism
  • 22q11.2 deletion

4

Characteristics of tuberous sclerosis

  • AD
  • cutaneous angiofibromas (adenoma sebaceum)
  • seizures
  • mental disability
  • pathology
    • CNS hamartomas and benign neoplasma
    • renal/visceral cysts
    • cardiac rhabdomyomas

5

Characteristisc of Marfan syndrome

  • AD
  • Mutation @ FBN1 gene @ chromosome 15 ==> connective tissue glycoprotein defect
  • associated sx:
    • tall stature
    • cystic medial necrosis ==> aortic dissection
    • lens dislocation
    • narrow face

6

Major fxns of stomach

  1. Protein digestin
    1. parietal cells ==> HCl
    2. chief cells ==> pepsinogen
    3. pepsinogen ==> pepsin ==> degrades proteins
  2. IF secretion ==> absorption of vitamin B12 
  3. Gastric resevoir = slow emptying into small bowel

7

Tx/recommendations after total gastrectomy

  • parental B12
  • to avoid dumping syndrome (colicky ab pain, nausea, diarrhea)
    • small meals
    • low dietary intake of simple sugars

8

Identify: A-H

  • A = Corpus Callosum
  • B = Lateral Ventricle
  • C = Caudate
  • D = Internal capsule
  • E = Putamen
  • F = Globus Pallidus
  • G = Amygdaloid nuclei
  • H = Internal Capsule

9

Cystic degeneration of putamen ==> dx?

Wilson's disease 

10

Presentation of GVHD

  • most common afer allogeneic bone marrow transplant or organs rich in lymphocytes (e.g. liver) or transfusion of non-irradiated blood
  • T cells @ donor tissue recognize host MHC antigens and attack
    • both CD4+ and CD8+ cells
  • skin, liver, and GI tract are generally most affected
  • Sx/Labs
    • w/in one week of transplant
    • liver damage ==> jaundice + elevated LFTs (ALT, AST, alk phos, bilirubin)
    • GI damage ==> diarrhea, intestinal bleeding, ab cramping, ileus
    • [severe cases] ==> skin desquamation

11

Meckel diverticulum characteristics

  • blind pouch connected to ileum <== incomplete obliteration of onphalomesenteric duct (connects midgut lumen and yolk sac cavity in fetal life)
  • ectopy ==> gastric, pancreatic and other types of cells/mucosa that may be found at meckel diverticulum
  • presentation
    • commonly ==> painless melana
    • may become infected/inflamed ==> ~appendicitis presentation

12

Ectopy definition

  • microscopically and functionally normal cells/tissue found in an abnormal location due to embryonic maldevelopment

13

Valsalva maneuver impact on venous return/heart murmurs

  • ==> decreased venous return
  • mitral valve prolapse & hypertrophic cardiomypathy ==> more audible
  • aortic stenosis ==> less audible

14

Common heart murmur in CHF

  • S3 = "ventricular gallop" <== blood rushing into partially filled ventricle or into a stiff ventricle
  • best heard w/bell of stethoscope @ apex in L lateral decubitus position + patient completely exhales (==> heart closer to chest wall)

15

Characteristics of duodenal lining

  • villi covered by simple columnar epithelium w/brush border
    • goblet cells ==> mucous secretion
    • APUD = amine precursor uptake and decarboxylation cells
  • @ lamina propria = crypts of lieberkuhn ==> deliver secretion to intervillar spacese
  • submucosa is deep to muscular mucosae
    • Brummer's glands ==> alkaline mucous

16

Characteristics of jejunal villi

  • more goblet cells vs. duodenal villi
  • crypts of Lieberkuhn persist; open into intervillar space
  • heavy lymphocytic infiltrate of lamina propria is common

17

Characteristics of ileum

  • ileum is similar to jejunum
  • Peyer's patches = lymphatic nodules ==> adjacent to villi/crypts

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