SPEX Pediatrics 4

Question 1

A 2-year-old presents with bloody diarrhea, abdominal pain, and pallor. Labs show microangiopathic hemolytic anemia, thrombocytopenia, and elevated creatinine. Which organism most commonly causes this condition?

Accepted Answer

Shiga toxin-producing E. coli (STEC O157:H7)

Answer

Hemolytic uremic syndrome (HUS) is most commonly caused by Shiga toxin-producing E. coli, especially O157:H7, often acquired from undercooked beef.

Question 2

Which of the following is the most common cause of nephrotic syndrome in children aged 1–8 years?

Accepted Answer

Minimal change disease

Answer

Minimal change disease is responsible for approximately 80% of nephrotic syndrome cases in children and typically responds well to steroids.

Question 3

A newborn has failure to pass meconium within 48 hours of birth. Rectal exam produces explosive passage of stool and gas. What is the most likely diagnosis?

Accepted Answer

Hirschsprung disease

Answer

Hirschsprung disease is caused by absence of ganglion cells in the distal colon; rectal decompression produces explosive stool release due to proximal distention.

Question 4

A 4-year-old presents with periorbital edema worse in the morning, frothy urine, and no hematuria. Urinalysis shows 4+ protein. What is the best initial treatment?

Accepted Answer

Oral prednisone

Answer

First-line treatment for childhood nephrotic syndrome (minimal change disease) is oral corticosteroids, typically prednisone.

Question 5

Which developmental screening tool is recommended by the AAP for all children at 18 and 24 months specifically to screen for autism spectrum disorder?

Accepted Answer

Modified Checklist for Autism in Toddlers (M-CHAT)

Answer

The M-CHAT is the AAP-recommended autism-specific screening tool used at 18 and 24-month well-child visits.

SPEX Exam Practice Test

SPEX Exam Practice Test

SPEX Pediatrics 4