Rx_Random Set #5 Flashcards Preview

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Flashcards in Rx_Random Set #5 Deck (28)
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1

Common drug/chemotherapy for testicular cancer (+ MOA + toxicities)

  • Bleomycin = active @ G2 phase of cell cycle; inhibits DNA synthesis via generation of free radicals that bind DNA and cause strand breaks
  • Toxicities
    • pulmonary fibrosis
    • myelosuppression
    • skin pigment changes

2

Bleomycin: use, MOA, toxicities

  • Bleomycin = used to tx testicular cancer and lymphoma
  • Bleomycin = active @ G2 phase of cell cycle; inhibits DNA synthesis via generation of free radicals that bind DNA and cause strand breaks
  • Toxicities
    • pulmonary fibrosis
    • myelosuppression
    • skin pigment changes

3

Clomiphen citrate: MOA, use

  • clomiphene citrate = selective estrogen receptor modulator (SERM) = antiestrogen @ hypothalamus ==> reduced feeback inhibition effect of estrogen
    • ==> increased GnRH ==> increased FSH/LH ==> ovulation or increased testosterone
  • Use:
    • females: commonly used for female infertility in polycystic ovarian syndrome
    • males: off-label use to improve fertility

4

Characteristics of Kawasaki's disease

  • acute necrotizing vasculitis of medium to small muscular arteries
    • suspected immune mechanism
  • generally effects children < 5yo
  • higher prevalence in Japanes population
  • sx:
    • fever
    • red eyes
    • erythematous rash on palms and soles
    • tachycardia
    • mucosal inflammation
  • labs:
    • normocytic anemia
    • neutrophillic leukocytosis
    • elevated ESR

5

Tx of Kawasaki's disease

  • aspirin (only condition in which to give aspirin to child)
  • AND intravenous immunoglobulin

6

Possible complications of Kawasaki's disease

  • coronary artery aneurysms

7

Fracture ==> lost contour and flattening of shoulder

  • proximal humerus fracture ==>
    • axillary nerve damage ==>
    • atrophy of deltoid muscle ==> lost contour/flattening

8

Lithium toxicity presentation

  • physical presentation
    • N/V
    • dysarthria (= speech difficulties)
    • lethargy
    • coarse hand tremors
    • ataxia, incoordination
    • hyperreflexia
    • vision changes
  • labs/physio presentation
    • nephrogenic DI ==>
    • high serum sodium
    • high serum osmolality
    • low urine osmolality

9

Lithium tetragoenic effects

  • Lithium during pregnancy ==> Ebstein's anomaly 
    • apically displaced tricuspid valve
    • atrialization of proximal right ventrical
    • enlarged right atrium
    • hypoplastic functional right ventricle
    • associated with atrial-septal defects

10

Cyanide effects

  • binds to iron @ final cytochrome complex in ETC
  • prevents oxygen from serving as the final electron acceptor in the ETC

11

Cyclophosphamide MOA + (toxicities + prevention)

  • Cyclophosphamide = chemotherapeutic DNA alkylating agent
    • tx of non-Hodgkin's lymphoma
  • myelosuppression
  • hemorrhagic cystitis
    • prevented w/mesna = binds cyclophosphamide metabolites in urine and neutralizes them

12

Myelosuppression characteristics

  • global depression of bone marrow activity ==>
    • overall lower cell count
    • anemia
    • decreased WBCs
    • thrombocytopenia
  • side effect of some cancer treatments

13

Common cause of acute bacterial endocarditis in drug-abusing patient

S. aureus

14

Most common cause of bacterial endocarditis

  • Viridans streptococci
    • usually subacute
    • colonize heart valves damaged by past rheumatic fever ==> L-side infective endocarditis
  • common source: dental procudeures ==> oropharynx flora into bloodstream

15

Common drug used to tx nephrogenic DI + MOA

  • Amiloride = potassium-sparing diuretic

16

Conditions associated with Marfan's syndrome

  • lens dislocation
  • pneumothorax
  • mitral valve prolapse
  • aortic root dilation ==> aortic dissection

17

Presentation of dissecting aortic aneurysm

  • dissecting aortic aneurysm ==> cardiac tamponade ==>
    • decreased ventricular filling
    • decreased CO
  • Beck's triad
    • hypotension
    • increased JVP
    • distant heart sounds
  • ECG:
    • diffuse low-voltage QRS complexes
    • electrical alternans = amplitude of QRS complex oscillates w/each beat

18

Nerves blocked by transvaginal pudendal nerve bock (+ common use)

  • pudendal nerve fibers = S2-S4 nerve roots
  • commonly used for anesthesia of perineum and inferior quarter of vagina 

19

T-ALL presentation

  • teenage males
  • thymic lymphomas (widened mediastinum)
  • elevated WBCs
  • weakness, fever, anorexia
  • petechiae (arms & legs)
  • diffuse lymphadenopathy
  • biopsy = pre-t cells, Tdt (terminal deoxynucleotidyl transferase) positive 

20

Tx of Pneumocystitis jirovecii pneumonia

  • first-line: trimethoprim-sulfamethoxazole (sulfa drug)
    • contraindicated in sulfa allergy
  • if sulfa-allergy: pentamidine

21

Mechanism of induction of lac operon in bacterio

  • Lactose (+ no glucose) stimulates lac operon
    • allolactose acts as inducer via binding and activation of repressor
  • No glucose ==> increased cAMP ==> binds cAMP receptor protein ==> binds lac operon promoter ==> transcription initiation

22

Parozysmal nocturnal hemoglobinuria: cause, consequences

  • cause = PIG-A glycosyl phosphatidulinositol anchor protein
  • consequences ==>
    • intravascular hemolysis (usually @ night)
    • hemosiderin in urine
    • anemia
    • episodic DVTs

23

Lethary, weakenss, bony pain + lytic bone lesions + M spike in gamma-immunoglobulin regions ==> dx?

Multiple myeloma

24

Multiple myeloma vs. ...other cause of lytic bone lesions?

25

Common complication in multiple myeloma that leads to systemic/renal problems + pathologic findings

  • multiple myeloma ==> primary amyloidosis
  • primary amyloidosis ==>
    • amyloid deposition @ mesangium and subendothelial space
    • glomerular obliteration ==> heavy proteinuria ==> end-stage renal disease
    • pathologic findings
      • staining w/congo red ==> positive w/apple-green birefringence

26

Location of renin-producing cells

  • juxtaglomerular cells = @ afferent arteriole

27

Presentation/mechanism of Bruton's agammaglobulinemia

  • recurrent bacterial infections in boys older than 6 months
    • X-linked defect in tyrosine kinase required for production of mature B cells
  • low levels of all immunoglobulin classes
  • normal T-lymphocyte counts

28

Immune respone: live attenuated vs. inactivated vaccines

  • live attenuated ==> cell-mediated AND humoral immunity
    • capable of replicating w/in cells of recipient
  • inactivated ==> b-lymphocyte (humoral) immunity w/out T-cell cell involvement

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