A 3-month-old African American boy was referred for evaluation of poor weight gain and vomiting. The infant had been evaluated by his primary care physician 15 times within the past 6 weeks; he had no change in symptoms despite various treatments.
The family expressed concerns about severe gastroesophageal reflux disease, developmental regression, conjunctivitis with corneal clouding, and coughing with feeds. The patient had had no fever, diarrhea, or recurrent infections (including pulmonary illness and otitis media).
Figure 1 – On admission, the infant had cloudy corneas and fine, brittle hair.
He also had facial seborrheic dermatitis.
History. The infant was adopted; he was born in a southern state and brought to New England within the first week of life. The birth parents’ histories were unremarkable. Results of newborn screening tests in the birth state were normal. Current medications included ranitidine and metoclopramide. The infant’s cow’s milk–based formula had been switched to soy formula because of persistent vomiting; he was receiving the appropriate volume and frequency of soy formula for his age. Immunizations were up-to-date.
Physical examination. Weight was less than the third percentile; length and head circumference were at the third percentile. Vital signs were nonworrisome. The infant had decreased activity. He had cloudy corneas without conjunctival injection (Figure 1); minimal rhinorrhea; minimal respiratory distress with diffuse, coarse breath sounds; mild abdominal distention; a moderate-sized, easily reducible umbilical hernia; fine, brittle hair; and moderate seborrheic dermatitis.
Figure 2 – Initial chest radiographs showed right upper lobe consolidation.
Laboratory tests and radiographic evaluation. Initial laboratory results indicated a slightly low ionized calcium level and an elevated alkaline phosphatase level. Chest radiographs showed right upper lobe consolidation (Figure 2). Pulmonology, ophthalmology, genetics, endocrinology, and gastroenterology specialists were consulted.
The list of possible causes of the patient’s condition was quite long at this point; more laboratory and radiographic studies were completed.
Further testing revealed significant fat-soluble vitamin deficiencies, elevated prothrombin time, subtle radiographic evidence of rickets, normal Δ1-antitrypsin level, low fecal elastase level, and elevated 72-hour fecal fat level. Pancreatic insufficiency was diagnosed.
Pilocarpine iontophoresis could not be reliably performed in this patient because of inadequate amounts of sweat. Cystic fibrosis mutation analysis revealed 2 gene mutations (ΔF508 and 3120+1 GA). The final diagnosis was cystic fibrosis with minimal respiratory involvement and significant pancreatic insufficiency, which resulted in clinical signs of fat-soluble vitamin deficiencies—xerophthalmia (vitamin A), rickets (vitamin D), xerosis (vitamin E), and coagulopathy (vitamin K).
(Discussion continues on next page.)
