Case 2: Poor Feeding and Physical Anomalies in a 1-day-old Male Newborn

Abstract

A male infant is born at 39 0/7 weeks of gestation with a birthweight of 2,917 g. He is born to a 28-year-old gravida 3, para 2-0-1-2 mother who received appropriate prenatal care. The infant requires no resuscitation at delivery, has Apgar scores of 9 and 9 at 1 and 5 minutes, respectively, and is transferred to the newborn nursery for routine care. Upon initial nursing evaluation in the nursery, the infant is noted to have 2,3-syndactyly of the bilateral feet (Fig 1) and a small phallus (Fig 2). The primary pediatrician’s initial examination reveals the syndactyly and a hypospadias with palpable testes in the inguinal canal. The infant is noted to have very poor latch and suck when attempting breastfeeding on the day of birth. One day after birth, the infant continues to have inability to feed at the breast. Follow-up examination notes ambiguous genitalia and laboratory/imaging studies are ordered. Initial laboratory investigation reveals a low total serum testosterone at 67 ng/dL (reference range for newborns: 75–400 ng/dL) and electrolytes remarkable for sodium of 141 mEq/L (141 mmol/L), potassium of 5.7 mEq/L (5.7 mmol/L), chloride of 109 mEq/L (109 mmol/L), bicarbonate of 24 mEq/L (24 mmol/L), serum urea nitrogen of 12 mg/dL (4.28 mmol/L), creatinine of 0.27 mg/dL (23.9 μmol/L), glucose of 54 mg/dL (3 mmol/L), and a serum calcium of 8.7 mg/dL (2.2 mmol/L). An …