A toddler with failure to thrive and impaired vision

A 2½-year-old boy came to the office for a routine check-up. His height and weight were below the fifth percentile and he was developmentally delayed. His parents noted that while he could walk unsupported, he could only say “mama” and “dada,” and had just recently started climbing stairs. His previous physician had diagnosed him with hypothyroidism, but he was not taking any medications.

The child’s birth history revealed that he was born to a 20-year-old G1P0 female via Cesarean section secondary to fetal distress at 42 weeks’ gestation. He subsequently spent 1 week in the neonatal intensive care unit due to hypoglycemia.

Following the office visit, the patient was admitted to the children’s hospital to investigate his failure to thrive and possible pituitary dysfunction. An ophthalmologic exam in the hospital showed that the patient was unable to follow objects, but did blink to bright light. Intermittent nystagmus was noted. A fundus exam revealed pale, hypoplastic optic nerves, bilaterally. Both nerves were also positive for the “double ring” sign (FIGURE 1).

Magnetic resonance imaging (MRI) of the brain (FIGURE 2) revealed hypoplastic genu of the corpus callosum, cavum septum pellucidum, ectopic posterior pituitary, and small anterior pituitary. There was also enhancement of the inferior hypothalamus.

FIGURE 1
Hypoplastic left optic nerve

FIGURE 2
MRI of the brain

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