NPS NPS Neonatal Physiology and Pathophysiology 3

Question 1

What is the most common chromosomal cause of hydrops fetalis in the US?

Accepted Answer

Turner syndrome (45,X)

Answer

Turner syndrome (45,X) is the most common chromosomal cause of non-immune hydrops fetalis due to lymphatic dysplasia causing nuchal cystic hygroma and generalized edema.

Question 2

A neonate presents with hypoglycemia, macrosomia, and polycythemia. What is the most likely maternal history?

Accepted Answer

Poorly controlled gestational diabetes

Answer

Infant of a diabetic mother (IDM) classically presents with macrosomia (from fetal hyperinsulinism), hypoglycemia after birth, and polycythemia from elevated fetal EPO.

Question 3

Which condition causes hypocalcemia in neonates born to mothers with hyperparathyroidism?

Accepted Answer

Maternal hypercalcemia suppresses fetal parathyroid gland development

Answer

Maternal hypercalcemia chronically suppresses fetal parathyroid gland development; after birth, the neonate cannot maintain calcium without maternal supply, causing severe hypocalcemia.

Question 4

Bell's staging system is used to classify the severity of which neonatal condition?

Accepted Answer

Necrotizing enterocolitis

Answer

Bell's staging classifies NEC into Stage I (suspected), Stage II (proven), and Stage III (advanced/complicated), guiding management decisions including surgery.

Question 5

Why does therapeutic hypothermia (TH) reduce brain injury in hypoxic-ischemic encephalopathy (HIE)?

Accepted Answer

It attenuates the secondary energy failure phase by suppressing glutamate excitotoxicity and apoptosis

Answer

TH targets the secondary injury phase (6–72 hours after hypoxia), reducing glutamate excitotoxicity, free radical generation, inflammation, and apoptosis.

NPS - Neonatal Pediatric Specialist Practice Test

NPS - Neonatal Pediatric Specialist Practice Test

NPS NPS Neonatal Physiology and Pathophysiology 3