A female neonate with DiGeorge syndrome develops severe muscle cramps and convulsions soon after birth. Which of the following is the cause of convulsions in this neonate?

DiGeorge syndrome is caused by a failure in the development of the third and fourth branchial pouches, resulting in agenesis or hypoplasia of the thymus and parathyroid glands, congenital heart defects, dysmorphic facies, and a variety of other congenital anomalies. As a result of parathyroid agenesis, patients with DiGeorge syndrome exhibit hypocalcemia, which manifests as increased neuromuscular excitability. Symptoms range from mild tingling in the hands and feet to severe muscle cramps and convulsions. DiGeorge syndrome does not feature any of the other choices.Diagnosis: DiGeorge syndrome