USMLE Step 1 Exam | Complete Practice Questions & Verified Answers
Heterophile ab NEGATIVE Mono-like syndromes *CMV
HHV-6
HIV
Toxoplasmosis
Wernicke's Aphasia -word salad: well-articulated, nonsensical speech paired with lack of lang
comprehension
-aud association cortex: post part of sup temporal gyrus
- supplied by MCA
Congenital Deficiency of Propionyl CoA Carboxylase -prevents conversion of propionyl CoA to methylmalonyl CoA
-propionyl CoA derived from= val, ile, met, thr, odd # FA, cholesterol side chains
-Propionic Acidemia: poor feeding, vomiting, hypotonia, lethargy, dehydration,
anion gap acidosis
Down Synd Comorbidities Neuro: MR, early onset Alzheimer's
Cardio: complete AV septal defect, VSD, ASD
GI: duodenal atresia, hirschprung disease
Endo: hypothyroid, DM1, obesity
Heme: ALL (> 5 yo) and AML (<5 yo)
Rheumatology: atlantoaxial stability
MCC of Hypoglycemia in EtOH-ics Thiamine def= suppression of GNG (pyruvate DH) and TCA cyle (alpha-KG DH)
MCC of Hypoglycemia in advanced renal insuff impaired clearance of insulin
Avoid Nitrates in Hypertrophic Cardiomyopathy bc... Nitrates decrease preload, which will increase the LV outflow tract... BUT since
the ventricle is abnormally shaped, there is an outflow obstruction
Mets through BM Clonal proliferation of cells can invade/ metastasize*
1. malignant cells to lose their cell-to-cell adhesion molecules (cadherins)
2. cell receptors to attach to laminin (a glycoprotein) in the basement membrane
and to release metalloproteinases (e.g., collagenases, stromelysins, gelatinases)
to degrade the basement membrane and other enzymes to degrade the
interstitial connective tissue- tissue inhibitors of metalloproteinases neutralize
these tumor-produced enzymes and limit the degree of invasion
3. cell receptors to attach to bronectin and other proteins in the extracellular
matrix (ECM) and to break it down
4. malignant cells to produce cytokines that stimulate locomotion, so that they
can move through basement membranes and the intracellular and extracellular
matrices
Bicuspid Aortic Valve Commonly presents in young, asymptomatic patient with soft systolic ejection at
right 2nd ICS
-can cause aortic regurg
MCC of Vaginal Candidiasis 1. Abx use= reduces lactobacilli pop
2. High estrogen levels- preg
3. System corticosteroid therapy
4. Uncontrolled DM
5. Immunosuppression, including HIV
Drug causes of SIADH -Carbamazepine
-Cyclophosphamide
-SSRI
MC Ankle Sprain due to inversion of plantar-flexed foot -Ant Talofibular Lig dmg
-ecchymosis at the ant-lat aspect of the ankle
Upper Brachial Plexus Injury - Musculocutaneous and Suprascapular N.
- dystocia mc in neonates; severe trauma mc in adults
- should adduction, elbow extension, and forearm pronation
, USMLE Step 1 Exam | Complete Practice Questions & Verified Answers
Patent foramen ovale -failure of septum primum and septum secundum to fuse after birth
-can lead to paradoxical emboli
Ventricular Septal Defect -MC occurs in membranous septum
-Acyanotic at birth bc of L to R shunt
Coronary Blood Flow Peak -at Early Diastole
-coronary perfusion driven by diastolic pressure
-tachycardia will decrease coronary perfusion
Right Dom Heart majority of people
-PDA comes off RCA
-SA and AV nodes supplied by RCA
Left Dom Heart -PDA comes off of LCX
- SA and AV node supplied by LCX
Increased Pulse Pressure hyperthyroidism, aortic regurgitation, aortic stiffening (isolated systolic
hypertension in elderly), obstructive sleep apnea ( sympathetic tone), exercise
(transient)
Decreased Pulse Pressure aortic stenosis, cardiogenic shock, cardiac tamponade, advanced heart failure
(HF)
Causes of Spontaneous Depol causing Hypokalemia, Hypermagnesemia, or prolonged QT interval
Tachyarrhythmias = all cause spontaneous depol of ventricles in phase 3 or 4 and it will cause an
extra AP in heart
Direct alpha 1 agonist mediated effects - vasc smooth muscle contraction= increased afterload and venous return=
increased DBP + SBP causes reflexive increase in vagal tone= dec HR and
slowed AV conduction
- mydriasis
- increased internal urethral sphincter tone and prostate contraction
Direct alpha 2 agonist mediated effects - CNS med decrease in BP
- decreased intraocular pressure
- decreased lipolysis
- decreased presyn NE release
- increased platelet aggregation
S. epidermidis - coag neg
-novobiocin sens
- infective endocarditis and infective arthritis in prosthetic pts
Asymptomatic heart defect in turner's synd -nonstenotic bicuspid aortic valve
-early systolic , high frequency click over right second IC space
Cardiac Changes w/ Normal Aging - decreased left ventricular chamber size
- shortened base- to- apex dimension
- ventricular septum becomes sigmoid and shape, with basilar portion bulging
into LV outflow tract
- atrophy of myocardium causes increased interstitial connective tissue, often
with concomitant extracellular amyloid deposition
- lipofucin pigment accumulation within cardiomyocytes
, USMLE Step 1 Exam | Complete Practice Questions & Verified Answers
ARDS Characterized by the development of hypoxemia and bilateral pulmonary
infiltrates in the absence of heart failure
-begins with initial injury of pul alveoli (smoke inhal) or pul endothelium (sepsis)
which leads to the recruitment of neutrophils- this worsens the situation and
leads to intraalveolar accumulation and hyaline membrane formation
-decreased lung compliance, increased work of breathing, worsened V/Q
mismatch, and normal PCWP
Renal Artery Stenosis (histo) medial fibroplasia, absent internal elastic lamina in areas of aneurysmal dilation
Paget's Disease associate Bone Tm OSTEOSARCOMA! arising from tibia, femur, humerus, and other bones
-pain doesnt resolve with OTC analgesics
DNA Laddering (Gel Electrophoresis) - DNA fragments in multiples of 180 bp each
- sensitive indicator of APOPTOSIS
- laddering done by specific endonucleases during haryorrhexis, cleaving DNA at
interucleosomal linker regions
- this is not seen in cancer cells, since they evade apoptosis
Warburg Effect malignant cells undergo high rates of glycolysis to produce macromolecules
necessary to sustain rapid cellular growth
Risk Factors of Endometritis -C-section delivery
-chorioamnionitis
-group B strep colonization
-intrauterine instrumentation
-preterm delivery
-prolonged labor
-prolonged ruptured membranes
-retained products of conception
SIGNS AND SX OF POSTPARTUM ENDOMETRITIS
-fever
-leukocytosis
-uterine tenderness
-foul smelling vaginal discharge
Metabolic derangements assoc with DKA metabolic acidosis, ketonemia, hyperglycemia, hyperkalemia, hyponatremia
-hyperammonemia can be observed due to muscle degradation
Pulmonary Embolism V/Q Mismatch, causes hypoxemia that increases ventilation and HR via a
chemoreceptor reflex
-hypocapnia b/c hypervent, but unable to compensate for hypoxemia
-resp alkylosis= increased ph and decreased PaCO2
Acanthosis Nigracans -Obesity/ insulin resistance
-Malignancy of GI or Lungs
Congenital Pyloric Stenosis -thickening of stomach wall, hypertrophy of smooth muscle pyloric stenosis
-palpable olive mass- epigastric region
-nonbilious projectile vomiting at 2-6 weeks of age
-assoc w/ Macrolides
-hypokalemia, hypochloremic, metab alkalosis
Heterophile ab NEGATIVE Mono-like syndromes *CMV
HHV-6
HIV
Toxoplasmosis
Wernicke's Aphasia -word salad: well-articulated, nonsensical speech paired with lack of lang
comprehension
-aud association cortex: post part of sup temporal gyrus
- supplied by MCA
Congenital Deficiency of Propionyl CoA Carboxylase -prevents conversion of propionyl CoA to methylmalonyl CoA
-propionyl CoA derived from= val, ile, met, thr, odd # FA, cholesterol side chains
-Propionic Acidemia: poor feeding, vomiting, hypotonia, lethargy, dehydration,
anion gap acidosis
Down Synd Comorbidities Neuro: MR, early onset Alzheimer's
Cardio: complete AV septal defect, VSD, ASD
GI: duodenal atresia, hirschprung disease
Endo: hypothyroid, DM1, obesity
Heme: ALL (> 5 yo) and AML (<5 yo)
Rheumatology: atlantoaxial stability
MCC of Hypoglycemia in EtOH-ics Thiamine def= suppression of GNG (pyruvate DH) and TCA cyle (alpha-KG DH)
MCC of Hypoglycemia in advanced renal insuff impaired clearance of insulin
Avoid Nitrates in Hypertrophic Cardiomyopathy bc... Nitrates decrease preload, which will increase the LV outflow tract... BUT since
the ventricle is abnormally shaped, there is an outflow obstruction
Mets through BM Clonal proliferation of cells can invade/ metastasize*
1. malignant cells to lose their cell-to-cell adhesion molecules (cadherins)
2. cell receptors to attach to laminin (a glycoprotein) in the basement membrane
and to release metalloproteinases (e.g., collagenases, stromelysins, gelatinases)
to degrade the basement membrane and other enzymes to degrade the
interstitial connective tissue- tissue inhibitors of metalloproteinases neutralize
these tumor-produced enzymes and limit the degree of invasion
3. cell receptors to attach to bronectin and other proteins in the extracellular
matrix (ECM) and to break it down
4. malignant cells to produce cytokines that stimulate locomotion, so that they
can move through basement membranes and the intracellular and extracellular
matrices
Bicuspid Aortic Valve Commonly presents in young, asymptomatic patient with soft systolic ejection at
right 2nd ICS
-can cause aortic regurg
MCC of Vaginal Candidiasis 1. Abx use= reduces lactobacilli pop
2. High estrogen levels- preg
3. System corticosteroid therapy
4. Uncontrolled DM
5. Immunosuppression, including HIV
Drug causes of SIADH -Carbamazepine
-Cyclophosphamide
-SSRI
MC Ankle Sprain due to inversion of plantar-flexed foot -Ant Talofibular Lig dmg
-ecchymosis at the ant-lat aspect of the ankle
Upper Brachial Plexus Injury - Musculocutaneous and Suprascapular N.
- dystocia mc in neonates; severe trauma mc in adults
- should adduction, elbow extension, and forearm pronation
, USMLE Step 1 Exam | Complete Practice Questions & Verified Answers
Patent foramen ovale -failure of septum primum and septum secundum to fuse after birth
-can lead to paradoxical emboli
Ventricular Septal Defect -MC occurs in membranous septum
-Acyanotic at birth bc of L to R shunt
Coronary Blood Flow Peak -at Early Diastole
-coronary perfusion driven by diastolic pressure
-tachycardia will decrease coronary perfusion
Right Dom Heart majority of people
-PDA comes off RCA
-SA and AV nodes supplied by RCA
Left Dom Heart -PDA comes off of LCX
- SA and AV node supplied by LCX
Increased Pulse Pressure hyperthyroidism, aortic regurgitation, aortic stiffening (isolated systolic
hypertension in elderly), obstructive sleep apnea ( sympathetic tone), exercise
(transient)
Decreased Pulse Pressure aortic stenosis, cardiogenic shock, cardiac tamponade, advanced heart failure
(HF)
Causes of Spontaneous Depol causing Hypokalemia, Hypermagnesemia, or prolonged QT interval
Tachyarrhythmias = all cause spontaneous depol of ventricles in phase 3 or 4 and it will cause an
extra AP in heart
Direct alpha 1 agonist mediated effects - vasc smooth muscle contraction= increased afterload and venous return=
increased DBP + SBP causes reflexive increase in vagal tone= dec HR and
slowed AV conduction
- mydriasis
- increased internal urethral sphincter tone and prostate contraction
Direct alpha 2 agonist mediated effects - CNS med decrease in BP
- decreased intraocular pressure
- decreased lipolysis
- decreased presyn NE release
- increased platelet aggregation
S. epidermidis - coag neg
-novobiocin sens
- infective endocarditis and infective arthritis in prosthetic pts
Asymptomatic heart defect in turner's synd -nonstenotic bicuspid aortic valve
-early systolic , high frequency click over right second IC space
Cardiac Changes w/ Normal Aging - decreased left ventricular chamber size
- shortened base- to- apex dimension
- ventricular septum becomes sigmoid and shape, with basilar portion bulging
into LV outflow tract
- atrophy of myocardium causes increased interstitial connective tissue, often
with concomitant extracellular amyloid deposition
- lipofucin pigment accumulation within cardiomyocytes
, USMLE Step 1 Exam | Complete Practice Questions & Verified Answers
ARDS Characterized by the development of hypoxemia and bilateral pulmonary
infiltrates in the absence of heart failure
-begins with initial injury of pul alveoli (smoke inhal) or pul endothelium (sepsis)
which leads to the recruitment of neutrophils- this worsens the situation and
leads to intraalveolar accumulation and hyaline membrane formation
-decreased lung compliance, increased work of breathing, worsened V/Q
mismatch, and normal PCWP
Renal Artery Stenosis (histo) medial fibroplasia, absent internal elastic lamina in areas of aneurysmal dilation
Paget's Disease associate Bone Tm OSTEOSARCOMA! arising from tibia, femur, humerus, and other bones
-pain doesnt resolve with OTC analgesics
DNA Laddering (Gel Electrophoresis) - DNA fragments in multiples of 180 bp each
- sensitive indicator of APOPTOSIS
- laddering done by specific endonucleases during haryorrhexis, cleaving DNA at
interucleosomal linker regions
- this is not seen in cancer cells, since they evade apoptosis
Warburg Effect malignant cells undergo high rates of glycolysis to produce macromolecules
necessary to sustain rapid cellular growth
Risk Factors of Endometritis -C-section delivery
-chorioamnionitis
-group B strep colonization
-intrauterine instrumentation
-preterm delivery
-prolonged labor
-prolonged ruptured membranes
-retained products of conception
SIGNS AND SX OF POSTPARTUM ENDOMETRITIS
-fever
-leukocytosis
-uterine tenderness
-foul smelling vaginal discharge
Metabolic derangements assoc with DKA metabolic acidosis, ketonemia, hyperglycemia, hyperkalemia, hyponatremia
-hyperammonemia can be observed due to muscle degradation
Pulmonary Embolism V/Q Mismatch, causes hypoxemia that increases ventilation and HR via a
chemoreceptor reflex
-hypocapnia b/c hypervent, but unable to compensate for hypoxemia
-resp alkylosis= increased ph and decreased PaCO2
Acanthosis Nigracans -Obesity/ insulin resistance
-Malignancy of GI or Lungs
Congenital Pyloric Stenosis -thickening of stomach wall, hypertrophy of smooth muscle pyloric stenosis
-palpable olive mass- epigastric region
-nonbilious projectile vomiting at 2-6 weeks of age
-assoc w/ Macrolides
-hypokalemia, hypochloremic, metab alkalosis
