Master the board step 3

Master the Boards: USMLE Step 3
High-Yield Developmental Milestones
The absence of milestone behavior or persistence of it beyond a given time
frame signifies CNS dysfunction. Exam questions typically describe an
infant’s/child’s skills and ask for the corresponding age.
Age
Milestone
Newborn reflexes Moro, grasp, rooting, tonic neck, and placing reflexes: Appear at birth and disappear at 4–6
months
Parachute reflex (extension of arms when fall simulated): Present at 6–8 months and persists
9 months Has pincer grasp, creeps and crawls, knows own name
12 months Cruises, says 1 or more words, plays ball
15 months Builds 3-cube tower, walks alone, makes lines and scribbles
18 months Builds 4-cube tower, walks down stairs, says 10 words, feeds self
24 months Builds 7-cube tower, runs well, goes up and down stairs, jumps with 2 feet, threads shoelaces,
handles spoon, says 2–3 sentences
36 months Walks downstairs alternating feet, rides tricycle, knows age and sex, understands taking turns
48 months Hops on 1 foot, throws ball overhead, tells stories, participates in group play
Behavioral Disorders
A 4-year-old boy has problems with bedwetting. The mother says that during the
day, he has no problems but is usually wet 6 of 7 mornings. He does not report
dysuria or frequency and has not had increased thirst. The mother also says that
he is a deep sleeper. Which of the following is the most appropriate next step in
management?
a. Give anticholinergics.
b. Give desmopressin.
c. Give prophylactic antibiotics.
d. Perform renal ultrasound.
e. Reassure mother that bedwetting is normal.
Answer: E. Bedwetting before age 5 (before bladder control is anticipated) is normal.
Enuresis
Enuresis is the involuntary voiding of urine, occurring at least twice a week
for at least 3 months in children over 5 years (when bladder control is anticipated).
Nocturnal enuresis (nighttime wetting) is more common in boys who
are usually continent, occurring within 2 years of daytime continence; address
with behavior therapy. Diurnal enuresis (daytime wetting) is more common
in girls and is associated with a higher rate of urinary tract infections (UTIs).
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