Case 3: A Rare Cause of Respiratory Distress and Excessive Salivation in a Term Infant

Presentation

A female infant is born at 39 weeks’ gestation via normal vaginal delivery to a 22-year-old primigravida woman. The woman's pregnancy had been uncomplicated. Antenatal ultrasonography findings are normal. Results of her perinatal toxoplasmosis, rubella, cytomegalovirus, and herpes simplex (TORCH) infection tests are negative, and group B Streptococcus screening result is negative. The membranes rupture just before delivery. Significant finding at delivery includes a meconium-stained amniotic fluid. The infant is vigorous at birth, with Apgar scores of 7 and 9 at 1 and 9 minutes, respectively, and a birthweight of 3,550 kg. She is sent to the normal nursery with her mother in good condition; 2 hours after birth, she develops respiratory distress with desaturation, and is immediately transferred to the NICU for further evaluation and treatment.

The infant is given continuous positive airway pressure of 5 cm H₂O. Fraction of inspired oxygen (Fio₂) is 50%; temperature 36.8°C; heart rate 130 beats/min; respiratory rate 70 breaths/min; and oxygen saturation 94%. Her blood pressure is 73/49 mm Hg.

On physical examination, she is awake and alert, has no dysmorphic features, and chest examination shows respiratory distress with intercostal retractions and diffuse inspiratory and expiratory wheezing. She is also noted to have excessive salivation. No significant organomegaly is found on abdominal examination, and the rest of the systemic examination findings are within normal limits. A blood culture specimen is obtained, and empiric treatment is started with ampicillin and gentamicin. Initial blood gas measurement reveals respiratory acidosis: pH 7.18, Pco₂ 69 mm Hg (9.18 kPa), and bicarbonate 25 …