A 6-month-old girl is brought to the clinic for routine care. She has not had any illnesses, although the mother says that the girl has trouble latching when breast feeding. She can roll over when prone but cannot roll from the supine position or sit unsupported. The infant was born vaginally after an uncomplicated pregnancy. Vital signs are within normal limits. On physical examination, the girl has a head circumference above the 97th percentile for her age and a full anterior fontanelle. The remainder of her physical examination is unremarkable. At birth, the girl's head circumference was at the 50th percentile. CT scan of the head reveals significant dilation of the lateral ventricles. If this condition is left uncorrected, which of the following is the most likely complication that will be seen in this patient?

Question

A 6-month-old girl is brought to the clinic for routine care.  She has not had any illnesses, although the mother says that the girl has trouble latching when breast feeding.  She can roll over when prone but cannot roll from the supine position or sit unsupported.  The infant was born vaginally after an uncomplicated pregnancy.  Vital signs are within normal limits.  On physical examination, the girl has a head circumference above the 97th percentile for her age and a full anterior fontanelle.  The remainder of her physical examination is unremarkable.  At birth, the girl's head circumference was at the 50th percentile.  CT scan of the head reveals significant dilation of the lateral ventricles.  If this condition is left uncorrected, which of the following is the most likely complication that will be seen in this patient?

Quizplus · Accepted Answer

11ec160b_3b06_b802_9249_c398f3348f5a_MD0001_00 Hydrocephalus is caused by abnormal accumulation of cerebrospinal fluid (CSF) in the brain. It is due to either overproduction or impaired drainage of CSF. Congenital hydrocephalus results from a structural malformation that causes impaired CSF drainage (eg, aqueductal stenosis, Chiari malformations, Dandy-Walker syndrome). Obstruction can also be secondary to infection (eg, cytomegalovirus, toxoplasmosis, meningitis) or intraventricular hemorrhage. Hydrocephalus must be distinguished from hydrocephalus ex-vacuo, which is normal CSF expansion following cerebral volume loss rather than abnormal CSF accumulation. Infants with hydrocephalus typically develop macrocephaly, poor feeding, muscle hypertonicity, and hyperreflexia. Hypertonicity and hyperreflexia result from upper motor neuron injury caused by stretching of the periventricular pyramidal tracts. Untreated hydrocephalus can lead to developmental delay and seizures. Treatment requires surgical placement of a shunt to bypass the obstruction, most often via the ventriculoperitoneal route. (Choices A, D, and E) Infection, hemorrhage, and cancer do not result from hydrocephalus but are instead potential causes of acquired hydrocephalus. (Choice B) Lower extremity hyporeflexia would result from damage to the lower motor neurons, which can occur in poliomyelitis or spinal muscular atrophy. Educational objective: Hydrocephalus in infants presents with macrocephaly and poor feeding. Imaging studies showing enlarged ventricles are characteristic. Untreated hydrocephalus leads to spasticity due to stretching of the periventricular pyramidal tracts, developmental delays, and seizures.

A 6-Month-Old Girl Is Brought to the Clinic for Routine