Measles severity and serum retinol (vitamin A) concentration among children in the United States.

Background: Studies in developing countries have shown that children with measles have low serum retinol concentrations and that lower retinol levels are associated with measles-related mortality. Vitamin A therapy has been shown to reduce mortality among African children with acute measles.
Objectives: To determine whether serum retinol concentration is low among children with measles in the United States and to determine whether retinol concentration is associated with illness severity.
Setting: Pediatric referral hospital and clinic in Milwaukee, WI, during the measles outbreak of 1989-1990.
Patients: One hundred fourteen patients < or = 5 years of age evaluated for serologically confirmed measles with serum obtained within 5 days following rash onset.
Methods: Serum retinol concentration was determined by high-performance liquid chromatography. Clinical data were collected by hospital record review. A modified Pediatric Risk of Mortality (PRISM) score was used to assess physiologic instability as a measure of illness severity.
Results: Retinol concentrations ranged from 0.25 to 1.18 mumol/L (median 0.58 mumol/L); 82 (72%) patients had low retinol concentration (< or = 0.70 mumol/L). Median retinol concentrations were lower among hospitalized patients (0.56 vs 0.70, P = .006) and patients with pneumonia (0.52 vs 0.64, P = .02) but higher among children with otitis media (0.63 vs 0.54, P = .01). Higher modified PRISM scores, reflecting greater physiologic instability, were associated with lower retinol concentration (beta coefficient -.0147, P = .025). In multivariate analysis, higher modified PRISM scores were associated with lower retinol concentration (beta coefficient -.0144, P = .025) even after controlling for hospitalization, presence of complications, race, age, receipt of Aid to Families With Dependent Children, gender, and interval from rash onset until serum was collected.
Conclusions: Among these children with measles in an urban United States community, retinol concentrations were depressed, and the degree of depression was associated with illness severity. Vitamin A therapy should be considered for children with measles in the United States who require hospitalization.