A 7-month-old girl is brought to the office due to decreased use of her left arm. Her parents have noticed that the patient grasps objects only in her right hand, and she keeps her left hand clenched. She also does not use her left arm to push her chest up while lying on her abdomen and is not rolling over. The patient was born at 31 weeks gestation to a 25-year-old primigravid woman who received corticosteroids, tocolytics, and magnesium sulfate for preterm labor management. The mother had inconsistent prenatal care and works as a receptionist at a veterinarian office. Today, the patient's head circumference, weight, and length are at the 50th percentile. Examination shows increased tone in the left upper and left lower extremities. Brachial and patellar reflexes are 3+ on the left and 2+ on the right. Tapping of the left Achilles tendon elicits multiple beats of clonus. Babinski reflex is present bilaterally. Sensations appear intact bilaterally. MRI of the brain shows white matter injury adjacent to the right lateral ventricle. Which of the following most likely contributed to this patient's condition?
Cerebral palsy | |
Etiology* | Imaging findings |
Prematurity/ |
|
Hypoxic-ischemic |
|
Perinatal stroke |
|
Intrauterine |
|
*Etiology is often multifactorial & the underlying cause may not be identified. | |
This patient has an early hand preference, upper motor neuron signs, and MRI findings consistent with cerebral palsy (CP). CP is characterized by nonprogressive motor dysfunction due to neurologic injury, most commonly in the setting of prematurity. Premature infants are at greatest risk for CP due to ischemia and necrosis in the poorly perfused area adjacent to the lateral ventricles, which is seen as white matter injury (ie, periventricular leukomalacia) on brain MRI. These patients may also have friable germinal matrix vessels that predispose to intraventricular hemorrhage.
CP can vary in presentation depending on the severity of neurologic injury. The following early signs should raise suspicion:
Infants with CP may initially be hypotonic, but spasticity typically develops with time. Increased tone is accompanied by hyperreflexia and often clonus.
Although spastic diplegia (bilateral lower extremity hypertonicity) is the most common CP subtype, this patient has spastic hemiplegia (ie, one side of the body is affected), which is consistent with her unilateral MRI findings.
(Choice B) Inherited thrombophilia increases the risk for perinatal ischemic stroke, which can lead to unilateral upper motor neuron findings and CP. However, MRI would show ischemic changes in a vascular distribution (most commonly the middle cerebral artery), not periventricular leukomalacia.
(Choice C) Lack of maternal folic acid intake is associated with neural tube defects such as spina bifida. Lower extremity tone and reflexes would be decreased in patients with spinal dysraphism.
(Choice D) Maternal magnesium sulfate administration can lead to hypotonia in the immediate newborn period but does not cause the long-lasting effects seen in this patient.
(Choice E) Intrauterine infection is associated with an increased risk for CP but generally results in global neurologic defects, not unilateral spasticity. In addition, MRI findings of congenital Toxoplasma gondii include diffuse intracranial calcifications, not periventricular white matter changes.
Educational objective:
Cerebral palsy is a nonprogressive neurologic injury that most commonly occurs in premature infants with periventricular leukomalacia. Findings can include motor delay, early hand preference, spasticity, and hyperreflexia.