pediatric highlights eduardo pino
TRANSCRIPT
USMLE Step 2 — Lesson 1 Pediatric Highlights for USMLE Step 2
Eduardo Pino, MD
NEWBORN-APGAR
Apgar Score 0 1 2
Appearance Blue, pale Body pink, ext blue All pink
Pulse (HR) 0 <100 >100
Grimace None Grimace Cough
Activity Limp Some flexion Active
Respiration Absent Slow irregular Good
NEWBORN-SKIN
• Subcutaneous fat necrosis
• Erythema toxicum
• Acne neonatorum
• Milia
• Hemangiomas
• Mongolian spots
• Nevus sebaceous
NEWBORN-HEAD
• Caput-scalp swelling, crosses suture lines, resolves in days
• Cephalhematoma - subperiosteal bleed, DOES NOT CROSS SUTURES, longer
resolution
• Fontanels-large, suspect hydrocephalus, hypothyroid
o Closure-anterior, 9-18 months
o Posterior, birth, 4-5 months
NEWBORN-EYES,NOSE
• Eyes
o Red reflex=lens clear
o White reflex=retinoblastoma
o Lens opacity=cataract
o Aniridia+hemihypertrophy=Wilms
• Nose
o Choanal atresia-blue baby pinks up on crying, catheter doesn’t pass nose
NEWBORN-ABDOMEN, GU
• Abdomen
o Masses-polycystic kidney most common
o Umbilical hernia-most close by 5 years
o Omphalocele-sac
o Gastroschisis-no sac
• GU
o Epispadias, hypospadias-don’t circumcise
o Undescended testes-bring down after 1 year
o Ambiguous genitalia-congenital adrenal hyperplasia (21 hydroxylase most
common)
NEWBORN-BIRTH INJURIES
• Fractures-clavicle most common-crepitus
• Forceps-facial nerve palsy, bruising
• Brachial plexus
o Erb-Duchenne:C5-C6, if C4, ipsilateral
diaphragmatic palsy
“waiter’s tip”
o Klumpke:C8-T1, “claw hand”
NEWBORN-SCREENING
• PKU-autosomal recessive
o mental retardation most common
o eczema, musty odor, FAIR HAIR, FAIR SKIN, BLUE EYES
• Galactosemia-autosomal recessive
o jaundice, hypoglycemia, cataracts
• Hypothyroid-T4 low, TSH high
o large fontanel, jaundice, mottled, constipation, large tongue, umb. hernia
NEWBORN-RESPIRATORY
• Common signs/symptoms- Cyanosis, tachypnea, nasal flaring, retractions, grunting
• Respiratory distress syndrome
o Surfactant deficiency, seen in preterm
o Ground glass appearance on X-ray
o Treat with surfactant, ventilator support
• Transient tachypnea of newborn
o Rapid descent, C/S
• Meconium aspiration syndrome
NEWBORN-JAUNDICE
• Physiologic
o Appears >24 hours of age
o peaks at 12.9 by 3 days
o resolves by 1 week
• Pathologic-first day, level >13, lasts > 1week
o Etiology-hemolysis-Rh, ABO
o biliary atresia-direct bilirubin,
o acholic stools
• Therapy-phototherapy only for indirect
NUTRITION
• Breast milk is best for infant
• Iron supplement after 6 months
• Contraindications-
o active, untreated TB
o syphilis
o AIDS
o herpes if breast lesions
o galactosemia
o varicella
• Formula-20 cal/oz
• Whole milk-only >1 yr. Bad for kidneys
GROWTH-HEIGHT
• Short stature
hypopituitarism
constitutional delay
familial short stature
deprivational dwarf
Turner
hypothyroidism
chronic disease
• Tall stature
normal-familial
obesity
endocrine-GH excess
o androgen excess
o hyperthyroidism
genetic
o Marfans
o Klinefelter
GROWTH-WEIGHT
Failure to Thrive
Malnutrition
Malabsorption
Allergies
Immune deficiency
Chronic disease
Obesity
<5% secondary to syndromes
Risk of obesity persisting to adults increases with advanced age of onset
DEVELOPMENT
• Newborn reflexes-most disappear by 4-6 mos, EXCEPT Babinski (18 mos),
parachute (never)
• Social smile 4-8 weeks
• Rolls onto back 4 mos
• Rolls onto stomach 5 mos
• Sits with support 6 mos
• Pincer grasp 9 mos
• 3 cubes at 15 mos, 4 at 18, 7 at 24
BEHAVIOR
• Attention deficit-inattentive, impulsive,distractible, hyperactive (4:1 males)
• Enuresis-primary nocturnal most common
• typically males, family history
• disorder of sleep/arousal
• treatment-time, alarms, imipramine DDAVP
• Encopresis-boys more common, usually psychological cause
USMLE Step 2 — Lesson 2 IMMUNIZATIONS
• NOT contraindications:
• Fever<105 after DPT
• Mild acute illness in otherwise well child
• Concurrent antimicrobial therapy
• Prematurity-immunize at chronological age
• Family history of seizures
• Family history of SIDS
IMMUNIZATIONS
• Don’t give live vaccines to immunocompromised
• Killed polio now recommended for initial series
• MMR-most effects 1-2 weeks later
• Delayed schedule-give as many as possible
• Missed immunizations-don’t start over
IMMUNIZATIONS-HIV
Vaccine No/ Moderate
Immunosupporess
Severe
Immunosupress
(Category 1,2) (Category 3)
DTP Yes Yes
OPV No No
IPV Yes Yes
MMR Yes No
Pneumococcal Yes Yes
Influenza Yes Yes
ID-SEPSIS/MENINGITIS
• Etiology- Age dependent
o Neonate-Group B Strep most common
E. coli
Listeria
o >2 months-pneumococcus most common
o College, military-meningococcus
• Clinical-bulging fontanel in infants
o Kernig, Brudzinski in older
• Know CSF findings
ID-SEPSIS/MENINGITIS
• Steroids useful in preventing H. flu sequelae
• Add vancomycin if Pneumococcus
• Rifampin prophylaxis for H. flu, Meningococcus
• Vaccines vs. H. flu, S. pneumoniae, N. meningitidis
ID-ENCEPHALITIS
• Etiology-viral
o Arbo, enteroviruses in seasonal epidemics
o HSV most common cause of sporadic
• Clinical-more abnormalities of mental function-confusion, delirium, combative, ataxia
ID-ENCEPHALITIS
• Diagnosis - PCR from CSF
• Temporal lobe involvement suspect HSV
• Treatment - acyclovir if HSV
ID-OSTEO/SEPTIC ARTHRITIS
• Osteomyelitis
o S. aureus most common
o Sickle cell - Staph, Salmonella
o Pasteurella after dog, cat bite
o Pseudomonas after sneaker puncture
o X-rays turn positive after 10-14 days
• Septic arthritis - Staph, also Strep
o Arthrocentesis test of choice
o Differential - cellulitis, JRA, synovitis, ALL
ID-PERTUSSIS
• Clinical
o conjunctivitis
o coughing spasms
o inspiratory whoop
o ·facial petechiae
• Lab-leukocytosis with lymphocytosis
o ·positive culture
o ·rapid fluorescent antibody stain
ID-PERTUSSIS
• History of incomplete immunizations
• Immunize to prevent, erythromycin to close contacts
• Erythromycin to patient shortens communicability
ID-RASH DISEASES
• Lyme disease-look for Long Island, Conn.
o Rash-erythema chronicum migrans
• Fifth’s disease-erythema infectiosum
o Rash-“slapped cheek”
o Parvovirus B19, can cause aplastic anemia
ID-RASH DISEASES
• Measles (rubeola)
o Cough, coryza, conjunctivitis, Koplik
o Rash accompanied by fever
• Roseola-rash after fever
• Rubella-3 day measles, lymphadenopathy
ID-RASH DISEASES
• Can immunize against measles, rubella, Lyme
• Rocky Mountain Spotted Fever
o Look for Carolinas
o Rash includes palms/soles
• Cat scratch-papule, granuloma, lymphadenitis
o PCR most sensitive for diagnosis
o Kittens transmit more than cats
ID-MISCELLANEOUS
• Mumps-orchitis rare before puberty
• HIV-most pediatric infections acquired at birth-zidovudine to mother decreases
transmission
• Mononucleosis - atypical lymphocytes
o Ampicillin rash
USMLE Step 2 — Lesson 3 POISONING
• Acetaminophen-check liver functions
o antidote: n-acetylcysteine
• Aspirin-ferric chloride test-qualitative
o metabolic acidosis with respiratory compensation in children
• Carbon monoxide-cherry red blood
o antidote-oxygen, hyperbaric
POISONINGS
• Tricyclic Antidepressants
• Leading cause of death
o seizures, arrhythmias
• Hydrocarbons - kerosene
o aspiration
• Organophosphates - DUMBELS
o antidote - atropine
POISONINGS
• Iron - signs of hemorrhagic gastroenteritis
o antidote - deferoxamine
• Lead - blood lead levels, lead lines
o antidote - EDTA, BAL
EYE
• Conjunctivitis-chemical most common <24h old
o Chlamydia most common infectious cause in newborn
• Strabismus-transient is normal up to 4 months old
EYE
• Amblyopia-“lazy eye”
o Hirschberg, Cover test
o patch good eye
• Cellulitis
o orbital-eyeball doesn’t move, proptosis preorbital-eyelids and surrounding
tissue
TEETH-PRIMARY ERUPTION
Lower(Mandibular) Upper(Maxillary)
Central Incisors 5-7 months 6-8 months
Lateral Incisors 7-10 months 8-11 months
Cuspids(canines) 16-20 months 16-20 months
First Molars 10-16 months 10-16 months
Second Molars 20-30 months 20-30 months
TEETH-SECONDARY
Lower Upper
Central Incisors 6-7 years 7-8 years
Cuspids 9-11 years 11-12 years
1st Premolars 10-12 years 10-11 years
2nd Premolars 11-13 years 10-21 years
1st Molars 6-7 years 6-7 years
2nd Molars 12-13 years 12-13 years
3rd Molars 17-22 years 17-22 years
EARS, NOSE, THROAT
• Otitis media
o Etiology - S. pneumo most common
H. flu nontypable
B. catarrhalis
o Meningitis most common intracranial complication
• Otitis externa-from repeated wetting
Etiology - Pseudomonas, S. aureus
Clinical-pain exacerbated by moving ear canal
EARS, NOSE, THROAT
• Sinusitis - S. pneumo, H.flu, Staph.
Symptoms-purulent nasal discharge headache, sinus tenderness
• Epistaxis - nose picking most common
• Pharyngitis - viral/bacterial (Group A strep)
o Throat culture is gold standard
o Complications - rheumatic fever
EARS, NOSE, THROAT
• Peritonsillar abscess-tonsil bulges, uvula deviates to non-involved side
“HOT POTATO VOICE”
• Retropharyngeal abscess-Strep, look at lateral X-ray of neck
• Cervical lymphadenitis-usually infectious
o Viral/bacterial pharyngitis, TB, cat scratch, rarely tumors
RESPIRATORY
• Foreign bodies-peanut most commonly aspirated
o Look for sudden onset respiratory distress, wheezing, may be witnessed
event
o Diagnosis-bronchoscopy, CXR hyper-inflated
• Croup-parainfluenza virus
o Clinical-barking cough, inspiratory stridor
o P/A neck film-STEEPLE SIGN
o Steroids beneficial
RESPIRATORY
• Epiglottitis H. flu type b
o Age- 3-10 years
o Clinical-dysphagia, drooling, muffled voice
o CHERRY RED EPIGLOTTIS
o THUMBPRINT SIGN on lateral neck
o Tx-secure airway, antibiotics
RESPIRATORY
• Asthma-Reversible airways disease
o wheezing is hallmark, no clubbing
o Differential-congenital malformations
foreign bodies
cystic fibrosis
bronchiolitis
o Tx-bronchodilators, steroids
o Prevent-cromolyn, leukotriene antagonist
RESPIRATORY
• Bronchiolitis-RSV, children<2 years
o Clinical-wheezing, rales, tachypnea
o Prevention-monoclonal antibodies
• Cystic fibrosis-autosomal recessive
o chromosome 7, long arm
o chronic obstruction-clubbing seen
o SWEAT TEST
RESPIRATORY
• SIDS-most common cause of death 1-12 mo
• Peak at 2-3 mo, winter, midnight-9 AM
• Sleep position
USMLE Step 2 — Lesson 4 CARDIOVASCULAR
• Innocent murmur-never diastolic
o never >2/6
o 3-7 years of age
o best at left lower, midsternal border
o musical, vibratory
o no significance
CARDIOVASCULAR CLASSIFICATION
STENOTIC R to L L to R MIXING
Aortic stenosis TOF PDA Truncus
Pulmonic stenosis Transposition VSD TAPVR
Coarctation Tricuspid atresia ASD Hypertrophic LH
CARDIOVASCULAR
• ASD-systolic ejection murmur
o WIDE FIXED SPLIT OF S2
• PDA-machinery murmur, to and fro
o wide pulse pressure, bounding pulses
o Tx-surgical closure indomethacin
• VSD-most common heart defect
o loud harsh pansystolic murmur
o 30-50% of small defects close by 1 year
CARDIOVASCULAR
• Endocardial cushion defect-Common AV canal
o Common in Down’s syndrome
o CHF early-feeding difficulty, sweat while feeding, tachypnea
• Coarctation of the aorta-common in Turner’s
o Weak/delayed/absent lower extremity pulses, Rib notching on CXR
CARDIOVASCULAR
• Tetralogy of Fallot- Most common cyanotic
o pulmonary stenosis
o VSD
o overriding aorta
o RV hypertrophy
o CXR-boot shaped heart, pulmonary markings o PE-cyanosis, single 2nd heart sound
o Complications-cerebral thrombosis, ischemia, brain abscess
CARDIOVASCULAR
• Transposition-most common with cyanosis in 1st 24 hrs.
o Keep ductus open with prostaglandin
o CXR-egg on a string
• Pulmonary atresia- cyanosis at 2-3 days
• Tricuspid atresia- single S2 pansystolic murmur
• Total anomalous pulmonary venous return
o CXR-snowman or figure 8
CARDIOVASCULAR
• Rheumatic fever- rheumatic fever-associated with Strep throat
J=joints
O=carditis (O looks like a heart)
N=nodules (subcutaneous)
E=erythema marginatum
S=Sydenham’s chorea
o minor criteria-fever, arthralgia, previous RF ESR, CRP, prolonged P-R interval + prior Strep infection
o complications-valve disease-mitral, aortic
CARDIOVASCULAR
• Hypertension
o Essential-no known underlying cause
o More common in adolescents
o Secondary-more common in infants and children
o Look for renal disease-UTI, obstructive lesion of urinary tract, prior umbilical
catheter as newborn
GASTROINTESTINAL
Diarrhea
• Viral-rotavirus most common
o adenovirus, Norwalk virus
• Bacterial-E.coli think of HUS
o Salmonella -tx prolongs carrier
o Shigella-tx with trimethop/sulfa
o Campylobacter-erythromycin
o C. difficile-think of prior antibiotic
o parasites-Giardia, cryptosporidium
GASTROINTESTINAL VOMITING
Constipation
• Voluntary withholding most common (functional constipation) outside of infancy
o also-imperforate anus
cystic fibrosis-meconium ileus
anteriorly displaced anus
Hirschsprung-aganglionosis
Dx by BIOPSY
GASTROINTESTINAL VOMITING
• Age related causes
o neonate-obstruction
o infants-gastroenteritis, reflux, allergy, over-feeding, inborn errors of
metabolism
o child/adolescent-gastroenteritis, toxic ingestion, appendicitis, pancreatitis
• Duodenal atresia-bilious vomiting common in Down’s, DOUBLE BUBBLE
GASTROINTESTINAL VOMITING
• Reflux - chronic, cough, vomiting, apnea
o pH probe is gold standard
• Pyloric stenosis - NONBILIOUS, PROJECTILE VOMITING
o more common in males, firstborn
o lab-hypochloremic, hypokalemic metabolic alkalosis
o Ultrasound test of choice
GASTROINTESTINAL BLEEDING
• Upper-esophagitis, ulcers, gastritis, epistaxis
• Lower-neonate-swallowed blood-Apt test
o necrotizing enterocolitis-premature, low Apgar, pneumatosis intestinalis
o other-milk allergy, gastroenteritis, ANAL FISSURE (infants)
GASTROINTESTINAL
• Inflammatory bowel disease-ulcerative colitis and Crohn’s
o Dx by biopsy
o both cause bloody stools, fever, abdominal pain
o Crohn’s-fissures, fistula, abscess
GASTROINTESTINAL
• Intussusception-typically 6-18 months
o Clinical-crampy abdominal pain CURRANT JELLY STOOL
o PE-sausage shaped abdominal mass
o ·Dx-barium enema-coil spring sign
GASTROINTESTINAL
• Meckel’s diverticulum-disease of 2’s
o 2% of population, 2:1 males, 2 years of age, 2 types of tissue, 2 feet from
ileocecal valve
o painless rectal bleed, can cause intussusception
o Dx-technetium scan
RENAL
• Acute Glomerulonephritis
o triad of hematuria,edema, hypertension
o follows Group A Strep infection
o C3 decreased
o Complications-renal failure, hypertension
• Alport’s
• X-linked dominant
• Clinical-microscopic hematuria, proteinuria,
HEARING LOSS, CATARACTS
RENAL
• Nephrotic syndrome-proteinuria,edema, hypoproteinemia, hyperlipidemia
o usually follows viral respiratory infection
o C3 normal
o Complications-INFECTION-peritonitis
• Urinary tract infection
o males more common <1 year, then females
o E. coli most common
o Urine culture is gold standard
USMLE Step 2 — Lesson 5 ORTHOPEDICS
• Intoeing
o Metatarsus adductus-can be brought to neutral
o Talipes equinovarus-heel also deviated
o Tibial torsion
o Femoral anteversion
ORTHOPEDICS
• Limping
o Congenital hip dysplasia-0-3 years, u/s
o Legg-Perthes-4-8 years-avascular necrosis of femoral head
o Slipped capital femoral epiphysis->11 years obese adolescent, think deficient
gonads
ORTHOPEDICS
• Popliteal cyst (Baker)-painless, nonpulsatile
• Osgood Schlatter-tenderness, swelling of tibial tubercle
o common in physically active pubertal children
• Radial head subluxation (nursemaid)
o sudden traction to arm
ORTHOPEDICS
• tumors-occur in adolescence, rapid bone growth
o Osteosarcoma-most common, risk if bilateral retinoblastoma o bone sclerosis on X-ray
o Ewing’s-“onion skin” on X-ray
ALLERGY/IMMUNOLOGY
• Allergic rhinitis-IgE mediated
o Clinical-sneezing, rhinorrhea, allergic salute, allergic shiners, nasal crease
o Tx-antihistamines, leukotriene antagonists
• Hereditary angioedema-C1 esterase inhibitor def.
• Bruton’s-all major immunoglobulins involved
o symptoms at 6-12 mos.-recurrent infections, esp. pneumococcus
o Tx-replace IgG
ALLERGY/IMMUNOLOGY
• DiGeorge-T cell deficiency
o TRUNCUS ARTERIOSUS, fishmouth, micrognathia
o NEONATAL HYPOCALCEMIA is 1st manifestation
• Wiskott-Aldrich: X-linked recessive
o MR TEXT-low IgM, Recurrent infections, T(and B) cell deficiency, Eczema,
Thrombocytopenia
RHEUMATOLOGY
• Juvenile Rheumatoid Arthritis
Types-
o polyarticular-many, small joints RF-, RF+
o pauciarticular-few, large joints
o type I-ANA+, girls, iridocyclitis
o type II-HLA B27+, boys, ankylosing spondylitis
o systemic-fever, rash, then joints
o Differential-rheumatic fever, SLE, Lyme, ankylosing spondylitis,
osteomyelitis, ALL
RHEUMATOLOGY
• Systemic lupus erythematosus-autoimmune
o BUTTERFLY (malar) rash
o renal involvement in children
o neonatal lupus-congenital heart block
• Mucocutaneous lymph node syndrome (Kawasaki)
o FEVER+ 4 of 5 of following: conjunctivitis, mucous membrane changes,
peripheral extremity changes, rash, cervical lymph nodes
o CARDIAC INVOLVEMENT
RHEUMATOLOGY
• Henoch-Schoenlein purpura
o Rash usually below waist
o Usually follows viral illness
o Can have renal, GI involvement
HEMATOLOGY
ANEMIA
• Iron Deficiency most common
o cause-low birth weight, diet (9-24 mos) blood loss (ulcer, Meckel, whole
cow’s milk in infants)
o clinical-pallor, irritability, murmur
o labs- ferritin, serum iron, binding capacity, FEP, Hgb o differential-lead, thalassemia, chronic disease
o tx-iron-see reticulocytosis in 72h, Hgb 3-4 wks
HEMATOLOGY
ANEMIA
• Hemolytic
o Hereditary spherocytosis-autosomal dominant
presents as anemia, jaundice
labs-OSMOTIC FRAGILITY TEST
tx-splenectomy
o Enzyme defects-pyruvate kinase, G6PD
HEMATOLOGY
ANEMIA
• Sickle cell anemia - develops after 2 months
o dactylitis 1st manifestation, splenic, bone infarcts, infections (Salmonella,
Pneumococcus)
• Dx-electrophoresis
HEMATOLOGY
• Idiopathic thrombocytopenia-autoimmune
o Usually follows viral infection
o Petechiae, but patient appears well
o Bone marrow-normal
o Tx-gamma globulin, steroids
• Hemophilia
o Factor VIII (classic, A)-X linked recessive
HEMARTHROSIS
Replace factor
ONCOLOGY
• Acute lymphocytic leukemia-most common childhood cancer
o clinical-acute onset, anorexia, pallor, fever, bone pain in 1/4
o dx-bone marrow
o tx-chemotherapy, radiation, transplant
o RELAPSE TO TESTES, CNS
• Wilms -nephroblastoma
o abdominal mass
o distorts renal outline
ONCOLOGY
• Neuroblastoma-many times abdominal,
o presents anywhere there is neural crest
o Increased catecholamines in urine
• CNS-most common solid tumors
o infratentorial (posterior fossa ) most common
cerebellar astrocytoma most common
clinical-morning headache, vomiting
o supratentorial-craniopharyngioma cause of short stature
USMLE Step 2 — Lesson 6 NEUROLOGY
• Seizures
o Febrile-most common
rapid rise of temperature
generalized, tonic-clonic, 10-15 mins
normal EEG
tx-treat fever
o Infantile spasms-West syndrome
EEG-hypsarrhythmia
tx-ACTH, prednisone
o Petit mal-3/sec spike/wave, ethosuximide
NEUROLOGY
• Progressive mental retardation
o Lesch-Nyhan-self-mutilation
gouty arthritis
o Wilson’s-disorder of copper metabolism
initial signs are liver related
Kayser-Fleischer rings
o Mucopolysaccharidoses-Hunter-X linked recessive, all others autosomal
recessive
o Tay-Sachs-lose developmental milestones, cherry red macula
NEUROLOGY
• Werdnig-Hoffman-spinal muscular atrophy
o Severe hypotonia-floppy baby
o Fasciculations, FROG LEG POSTURE
o EMG-fibrillations
o muscle bx-denervation
o nerve bx-slowed conduction
o Autosomal recessive
• Guillain-Barré-follows viral illness
o Ascending weakness, paralysis, lose deep tendon reflexes
tx-supportive, plasmapheresis, IVIG
NEUROLOGY
• Duchenne muscular dystrophy-X linked rec
o most common inherited neuromuscular disease
o Hip girdle weakness, Gower’s sign
o dx-greatly elevated creatine kinase, muscle bx
• Neurofibromatosis-von Recklinghausen
o Café-au-lait spots, axillary/inguinal freckling
o Lisch nodules, neurofibromas, acoustic neuroma
o autosomal dominant, risk for malignancy
NEUROLOGY
• Tuberous sclerosis-autosomal dominant
o Ash leaf spot, sebaceous adenomas, shagreen patch, periventricular
calcified tubers on CT
o seizures very common
• Sturge-Weber-facial nevus-port wine stain
o seizures difficult to control
o intracranial calcifications
o mental retardation
ABUSE
• Clinical-unexplained injury
o physical and injury don’t correlate
o lash marks, loop marks
o bite >3 cm=adult
o RETINAL HEMORRHAGE=shaken
o old healing fractures, bruises
o venereal disease in prepubertal child
• Tx-treat any injury, infection
o document, REPORT
ADOLESCENT
• Know Tanner stages
• Breast buds 1st sign of puberty in females
• Testicular enlargement 1st sign in males
• Mortality-Accidents, especially motor vehicle
o Suicide-males more successful
o Homicide
o Cancer-leukemia, Hodgkin’s, bone
• Normal-breast asymmetry, gynecomastia, irregular menses
• Acne-hormones, dirt, bacteria
Pediatric Highlights for USMLE Step 2
Eduardo Pino, MD
End