Uworld – 46

Front 1

Hypospaidas

Back 1

-in males, incomplete fusion of urethral (urogenital) folds results in hypospadias

-hypospadias is abnormal opening of urethra proximal to glans penis, along ventral shaft of penis

Front 2

Epispadias

Back 2

-less common than hypospadias

-urethral opening on dorsal side of penis

-due to faulty positioning of genital tubercle

Front 3

Total flow

Back 3

total flow = flow velcoity x cross sectional area = constant

i.e., Q = A1V1 = A2V2

Front 4

Classic galastosemia

Back 4

-autosomal recessive disease

-patients with galactosemia are homozygous for a defective galactose-1-phosphate uridyltransferase gene

-in general, most enzyme deficiencies follow autosomal recessive inheritance
--vs. most diseases due to defective non-catalytic proteins follow autosomal dominate pattern

Front 5

C. perfringens

Back 5

-clostridium = gram-positive rod

-causes late-onset food poisoning and clostridial myonecrosis (gas gangrene)

-the food poisoning is toxin-mediated, late-onset, and clinically causes transient watery diarrhea

Front 6

Maple syrup urine disease

-presentation: vomiting, irritability, lethargy, and diapers that smell like "burned sugar"

Back 6

-Maple syrup urine disease (MSUD) is disorder due to defective breakdown of branched chain amino acids – leucine, isoleucine, valine.

-degradation of these amino acids involves transamination to their respective alpha-ketoactids, which are then metabolized by an enzyme complex called BRNACHED-CHAIN ALPHA-KETOACID DEHYDROGENASE

-this enzyme (like pyruvate dehydrogenase) requires "tender loving care for nancy"

--coenzymes: thiamine pyrophosphate, lipoate, coenzyme A, FAD, NAD

--some patients with maple syrup urine disease improve with high-dose thiamine treatment (thiamine-responsive), but most still require lifelong dietary restrictions

Front 7

Patent ductus arteriosus

Back 7

-characterized by continuous murmur, heard best in left infra-clavicular region, with maximal intensity at S2

-small PDA is often asymptomatic – usually detected incidentally

-PDA most common in patients born prematurely, and those with cyanotic congenital heart disease (PDA = shunt)

Front 8

Atrial septal defect

Back 8

-much less common than a PDA

-can cause continuous murmur in rare instances – usually when associated with mitral valve obstruction due to an elevated pressure gradient across the atria (Lutembacher syndrome)

Front 9

Hyper-osmotic volume contraction

Back 9

-volume contraction or expansion can be classified as iso-osmotic, hypo-osmotic, or hyper-osmotic.

-loss of free water with retention of electrolytes is seen in diabetes insipid us, and in excessive seating without fluid and solute replacement.

--these are examples of hyper-osmotic volume contraction (loss of fluids, with rise in serum osmolarity)

Front 10

Hibernating myocardium

Back 10

-repetitive ischemia or persistent hypo perfusion of myocytes can result in chronic but REVERSIBLE loss of contractile function – known as "hibernation"

-persistent or repetitive low flow state causes myocardial hibernation – can be reversed by re-perfusion

Front 11

Myocardial stunning

Back 11

-less sever form (than hibernating myocardium) of ischemia-induced reversible loss of contractile function

--repetitive stunning can result in hibernation

Front 12

Ischemic preconditioning of myocardium

Back 12

-ischemic preconditioning = development of resistance to infarction by cardiac myocytes previously exposed to repetitive non-lethal ischemia

Front 13

Ventricular remodeling

Back 13

-ventricular remodeling involves chronic changes in mass, volume, shape, and myocyte composition of the heart – compensates for increased hemodynamic load

Front 14

Lesions involving CN 3

Back 14

-CN 3 lesions cause ptosis (drooping upper eyelid), downward and laterally deviated eye, impaired pupillary constriction and accommodation, and diagonal diplopia (vertical and horizontal diplopia)

-most dreaded causes of CN 3 palsy is an enlarging intracranial aneurysm

Front 15

Azithromycin for Mycobacterium avium

Back 15

-mycobacterium avium is a common opportunistic pathogen that causes disseminated disease (mycobacterium avium complex, MAC) in HIV-positive patients

-weekly AZITHROMYCIN is used as prophylaxis in patients at risk for MYAC
--e.g., HIV+ patients with CD4 counts less than 50 cells/mL

Front 16

Bell's palsy symptoms

Back 16

-in addition to unilateral facial paralysis, patients with Bell's palsy may experience decreased tearing, hyperacusis (sensitivity to volume), and/or loss of taste sensation in ANTERIOR 2/3 OF TONGUE

Front 17

Posterior tongue taste

Back 17

-glossopharyngeal nerve (CN 9) provides taste sensation from posterior 1/3 of tongue

-vs. facial nerve (CN 7) provides taste from anterior 2/3 of tongue.

Front 18

G6PD deficiency, vs. glutathione reductase deficiency

Back 18

-glucose 6-phosphate dehydrogenase deficiency is defect in HMP shunt that impairs glutathioine reduction, due to failure to produce NADPH

-glutathione reductase deficiency causes similar clinical picture, due to similar patho-physiology

Front 19

Anorexia nervosa

Back 19

-most common eating disorder in adolescent girls from affluent families

-criteria include:

--body weight at least 15% below normal, with refusal to maintain normal weight

--amenorrhea for three months

--distorted body image (views self as obese)

--fear of gaining weight despite being underweight

-FEMALE ATHLETE TRIAD often seen with anorexia nervosa:
--eating disorder
--amenorrhea
--osteoporosis

Front 20

-Rubeola virus presentation

-CCCK

Back 20

-tetrad of cough, coryza (nasal inflammation/congestion), conjunctivitis and Koplik spots is diagnostic of measles (rubeola)

-Koplik spots are tiny white or blue-gray lesions on buccal mucosa that precede the maculopapular skin rash

Front 21

Th2 cells and isotope switching

Back 21

-Sensitized Th2 cells secrete IL-4 and IL-13 – together promote B-lymphocyte class switching for IgE synthesis

-also secrete IL-5, which activates eosinophils and promotes IgA synthesis

-excess of these Th2-produced lymphokines may contribute to pathogenesis of extrinsic allergic asthma

Front 22

IL-1

Back 22

-secreted by macrophages to stimulate helper T-cells

Front 23

IL-3

Back 23

-secreted by helper T cells to recruit bone marrow stem cells

Front 24

gamma-interferon

Back 24

-secreted by helper T cells, mainly to activate macrophages

Front 25

TGF-beta

Back 25

-growth factor involved in tissue regeneration and repair

Front 26

Dofetilide action

-K+ blocker (class 3 anti-arrhythmic)

Back 26

-class 3 anti-arrhythmic agents block potassium efflux from cardiac myocytes

--slow potassium efflux from cardiac myocyte

--prolong PHASE 3 of myocyte action potential

Front 27

ACE inhibitors and first-dose hypOtension

Back 27

-first-dose hypotension is an adverse effect when initiating ACE inhibitors

--predisposing risk factors for first-dose hypotension include hyponatremia, hypovolemia (secondary to diuretics), low baseline blood pressure, high renin or aldosterone levels, renal impairment, and heart failure.

--patients taking thiazide or loop diuretics can be hypovolemic and hyponatremic, thus potentiating the effects of first-dose hypotension

-to minimize risk for first-dose hypotension, initiate low dosages to at-rsk patients, and proceed with cautious dosage titration and BP monitoring

Front 28

Amiodarone and thyroid function

Back 28

-amiodarne is a class 3 anti-arrythmic drug

-used to suppress life-threatening cardiac conduction abnormalities

-thyroid function tests should be monitored in patients receiving amiodarone therapy

-amiodarone is associated with many side effects:

--thyroid dysfunction
--corneal micro-deposits
--blue-gray skin discoloration
--drug-related hepatitis
--pulmonary fibrosis

Front 29

Epithelium of respiratory tract

Back 29

-psuedostratified columnar mucus-secreting epithelium:
--nose, paranasal sinuses, nasopharynx, most of larynx, and tracho-bronchial tree

-Stratified squamous epithelium:
--found only in oropharynx, laryngopharynx, anterior epiglottis, upper half of posterior epiglottis, and VOCAL FOLDS (true vocal cords)

Front 30

Suarachnoid hemorrhage

Back 30

-sub-arachnoid hemorrhage presents with generalized excruciating headache ("worst headache of my life")

-usually occurs due to rupture of saccular (berry) aneurysms, or arteriovenous malformations

-berry aneurysms of circle of Willis are associated with autosomal dominant polycystic kidney disease

Front 31

Sarcoidosis

Back 31

-sarcoidosis most commonly affects young black women

-presents with malaise, cough, varied cutaneous finding (including erythema nodosum)

-chest X-ray shows BILATERAL HILAR LYMPHADENOPATHY

-trans-bronchial biopsy with NON-CASEATING GRANULOMAS is necessary for diagnosis