Retrospective Observational Analysis of Free Serum Retinol in a Cohort of Pediatric Patients with Short Bowel Syndrome and Intestinal Failure

Vitamin A is a fat-soluble vitamin that plays an important role in immune function, vision, and growth. We analyzed serum-free retinol deficiency in pediatric patients with intestinal failure (IF) or short bowel syndrome (SBS) to determine which clinical factors contribute to vitamin A deficiency in this population. A single-center, retrospective review of 32 children with IF or SBS was conducted examining 6 categorical classifications of patients to test for increased risk of vitamin A deficiency, building a univariate logistic regression model for each category. Few serum assessments were consistent with deficiency (11 out of 347 tests obtained over 153 patient-years). Among these 11 low levels occurring in three patients, 6 were borderline or nearly normal for age and without associated symptoms, and 4 were obtained from one patient with significant ileal inflammation in the context of a STAT1 mutation. One level was obtained in one patient without a corresponding C-reactive protein level, and this patient had 23 subsequently normal serum-free retinol levels. In this small sample size, no patients were symptomatic. In patients who had at least 1 vitamin A test during the prior year without any deficient measurements, there was a 1.3% chance of obtaining a deficient vitamin A level upon subsequent measurement. A low risk of vitamin A deficiency was seen over the course of 153 patient-years, suggesting that frequent, repeated vitamin A assessment may not be needed in patients with normal vitamin A status early in their post-operative IF course.