Rx_Random Set #8 Flashcards Preview

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Flashcards in Rx_Random Set #8 Deck (26)
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1

Classic exam findings in osteoarthritis

  • heberden's nodes = swelling @ distal interphalangeal joints
  • bouchard's nodes = swelling @ proximal interphalangeal joints

2

Flucytosine: MOA + use

  • antifungal agent used to treat systemic fungal infections
  • MOA = pyrimidine antimetabolite: inhibits DNA syntehsis by conversion to fluorouracil which competes w/uracil
    • selective for fungal cells bc enzymes required for entry and activation are found in low levels in mammalian cells

3

Cause of heriditary spherocytosis

  • lack/mlfxn of RBC proteins spectrin or ankyrin

4

Mechanism/presentation of heriditary spherocytosis

  • malfxn of spectrin/ankyrin ==> round sperocytes ==> prone to hemolysis, esp. @ spleen
  • sx/signs
    • jaundiced after viral illness
  • FHx
    • splenectomies
  • Dx
    • spherocytes on peripheral smear
    • osmotic fragility test

5

Common histologic finding in squamous cell carcinoma of bladder

keratin pearls

6

Most common cause of squamous cell carcinoma of bladder (in world)

  • helminth infection
  • schistosoma haematobium ==> eggs @ bladder wall ==> chronic irritation ==> cancer

7

Final enzyme in purine salvage pathway

  • xanthine oxidase
    • converts xanthine ==> uric acid
    • inhibited by allopurinol (medication used to prevent gout attacks)

8

Presentation/mechanism of alkaptonuria

  • AR disorder of homogentisic acid oxidase
    • enzyme that helps degrade tyrosine
  • ==> accumulation of homogetisic acid ==>
    • cartilage (joint) damage + dark color
    • heart valve damage
    • formation of kidney stones
    • excretion in urine ==> black urine

9

Brain abnormality associated with Patau syndrome

  • holoprosencephaly
  • commonly: midline forebrain structures affected
    • optic tracts/bulbs
    • corpus callosum
    • pituitary
    • hypothalamus

10

MOA of vasopressin @ V2 receptors

  • V2 receptors located @ kidney collecting duct
  • ADH/vasopressin ==> V2 ==> activation of adenylyl cyclase via Gs subunit ==> increased cAMP ==> insertion of aquaporin proteins @ apical membrane ==> increased urine concentration

11

Methotrexate: MOA, uses

  • methotrexate = folic acid analog antimetabolite ==> inhibition of dihydrofolate reductase
    • DHFR involved in synthesis of purines and some amino acids
  • uses
    • inflammatory conditions
      • rheumatoid arthritis
      • IBD
    • chemotherapy
      • breast carcinoma
      • lung carcinoma
      • ALL
      • non-hodgkin's lymphoma
      • etc.

12

Cyclophosphamide: MOA, uses

  • MOA: alkylating agent ==> adds alkyl group to DNA ==> interferes w/DNA synthesis
  • Uses
    • immunosuppressant
      • SLE
      • MS
      • autoimmune hemolytic anemia
      • **restricted use due to severe side effects
    • chemotherapy
      • breast carcinoma
      • non-Hodgkin lymphoma
      • ovarian carcinoma

13

Hep A: viral type, transmission, presenation, tx

  • ssRNA
  • fecal-oral transmission
    • esp. endemic areas w/contaminated water supply
  • sx: jaundice, N/V, fever, abdominal pain, hepatomegaly
  • tx: supportive care

14

Heart murmur in patient w/SLE ==> ?

  • most-likely indicates Libman-Sacks endocarditis
  • LSE = small vegetation of fibrin + inflammatory cells, often on both sides of valve leaflets
    • rarely cause valvular complications or embolize 

15

Common pathologic feature in lungs of smokers

  • metaplasia of pseudostratified ==> stratified squamous eptihelium

16

Which of following types of epithelium not normally present in the lung, lines the bronchu shown in this image (hx: smoking)

A. pseudostratified columnar

B. simple squamous

C. stratified columnar

D. stratified squamous

E. transitional

D. stratified squamous

17

Treatment for depression w/safe cardiac profile

  • Monoamine oxidase inhibitors
    • e.g. phenelizine

18

Characteristics of WAGR syndrome

  • presents in childhood
  • Wilm's tumor (kidney tumor)
  • Aniridia (partial or complete lack of iris)
  • genital anomolies
  • mental disability

19

Presentation/mechanism of polyarteritis nodosa

  • vasculitis of the small-medium arteries
    • necrotizing immune complex formation
  • non-specific sx from end-organ damage related to blood flow
    • MSK, cutaneous, GI, cardiac, renal, neuro
    • lung's are spared
  • often associated with Hepatitis B

20

Acarbose: MOA, use, SE

  • MOA: alpha-glucosidase inhibitor ==> decrease hydrolysis and absorption of di/polysaccharides @ intestinal brush border
    • ==> decreased postprandial hyperglycemia
  • Use
    • management of T2DM
  • SE
    • GI: abdominal cramps, diarrhea, flatulence
    • contraindicated in poor liver fxn

21

Presentation of herniation of L5-S1 disc

  • radiculopathy of S1 nerve root ==>
  • decreased sensation @ post. leg + lateral foot
  • diminished ankle jerk reflex
  • weak plantarflexion of foot
  • back pain radiating to leg
  • positive straight leg test

22

Presentation of Vit D deficiency

  • hypocalcemia
  • secondary hyperparathyroidism
  • hypophosphatemia

23

Peripheral smear and lab results in DIC

  • Labs
    • elevated prothrombin
    • elevated partial thromboplastin time
    • elevated D-dimer (=fibrin degradation products)
  • Peripheral smear
    • shicstocytes ("helmet" cells)

24

Presentation of indirect inguinal hernia

  • most often = newborn male infants
    • peritoneum passes through internal inguinal ring and enters scrotum
    • ==> enlarged scrotum + pain
  • covered by all three layers of fascia

25

Possible late presentation of spina bifida occulta

  • low back pain
  • intact patellar deep tendon reflex
  • x-ray shows incomplete fusion of S1 vertebra

26

Causes of spina bifida occulta

  • sbo = neural tube defect (incomplete closure of neural tube)
    • occurs during first month of gestations
  • associated w/maternal factors:
    • folate deficiency
    • anticonvulsant medication
      • e.g. Valproic acid
    • diabetes

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