Index of Suspicion in the Nursery

Abstract

A 3-week-old previously healthy infant presents to her pediatrician's office with lethargy that began after she woke from sleep with projectile emesis. She has not fed in several hours. In the office, she is sleepy but appears otherwise normal; her rectal temperature is 36.0°C. After observation at home for a few more hours, she still has not fed. Her blood glucose measures 101 mg/dL (5.6 mmol/L). Urine is sent for culture, and she is admitted to the hospital for further evaluation. Physical examination reveals a temperature of 33.4°C, so she is placed in an external warming device. She has normal results of a complete blood count, comprehensive metabolic panel, and ammonia and lactate measurements. Serum amino acids and urine organic acids evaluations are ordered. A lumbar puncture reveals 410,000/mm3 red blood cells and 825/mm3 white blood cells. She is started on ampicillin and gentamicin. The patient subsequently breastfeeds well and seems more alert. However, a few hours later, she has two episodes during which she stiffens and screams for 15 to 30 seconds, followed by lethargy. Arrangements are made to transfer her to the regional hospital pediatric intensive care unit. Additional testing is obtained before transfer. A term baby is delivered by emergency cesarean section because of fetal heart decelerations, failure to progress, and meconium-stained amniotic fluid during labor. The mother is a 23-year-old G2P1 woman whose serology results are unremarkable, except for group B Streptococcus colonization. She received good prenatal care. She presented for induction with a large-for-gestational age infant. In addition to meconium-stained amniotic fluid, labor is complicated by a maternal temperature of 38.4°C. Three doses of ampicillin are administered after rupture of membranes 12 hours before delivery. Following delivery, the infant does not cry. The infant's birthweight is 3,585 g, head circumference is 34 cm, …