To the Editor:
We read with great interest the article by Singh et al. (1) which provided a new idea on the effect of vitamin A in neonatal respiratory disease. Further clinical research may be needed, but some wonders exist which are as follows:
-
1
Three groups were set in the article: I = control; II = surfactant; and III = surfactant + vitamin A. Maybe groups II and III should be set, II = surfactant (100% activity) and III = surfactant (60% activity) + vitamin A, because the surface activity was 40% lower in group III than that in group II, and there was no significant difference of gas exchange between groups II and III. Did vitamin A have the efficacy equal to surfactant with 40% activity or what?
-
2
The study should have included both preterm and term infants. Although vitamin A supplementation could be more effective on premature infants with chronic lung disease (CLD), recent research suggested that 25% of infants remain vitamin A deficient despite vitamin A supplementation (2). The persistence of biochemical vitamin A deficiency might be due to impaired vitamin A transportation. Transthyretin, a major vitamin A transport protein, has been suggested to be reduced by inflammation (3).
-
3
Intramuscular administration of 5000 IU vitamin A every other day for 4 wk could decrease the incidence of CLD. How much and how often should vitamin A be supplemented to premature infants by intratracheal administration to ensure the effect?
-
4
How about vitamin A supplemented together with retinoic acid? Recent study has shown that a combination of vitamin A (the nutrient) and retinoic acid (the metabolite) improved more tissue retinoid stores than either vitamin A or retinoic acid alone in infant rats (4).
In conclusion, although intramuscular administration of vitamin A has been suggested to reduce the incidence of CLD, intratracheal administration of vitamin A may provide a new way with more absorb dosage and less pain.
References
Singh AJ, Bronshtein V, Khashu M, Lee K, Potts JE, Friel J, Chessex P 2010 Vitamin A is systemically bioavailable after intratracheal administration with surfactant in an animal model of newborn respiratory distress. Pediatr Res 67: 619–623
Tyson JE, Wright LL, Oh W, Kennedy KA, Mele L, Ehrenkranz RA, Stoll BJ, Lemons JA, Stevenson DK, Bauer CR, Korones SB, Fanaroff AA 1999 Vitamin A supplementation for extremely-low-birth-weight infants. N Engl J Med 340: 1962–1968
Ambalavanan N, Ross AC, Carlo WA 2005 Retinol-binding protein, transthyretin, and C-reactive protein in extremely low birth weight (ELBW) infants. J Perinatol 25: 714–719
James ML, Ross AC, Bulger A, Philips JB 3rd, Ambalavanan N 2010 Vitamin A and retinoic acid act synergistically to increase lung retinyl esters during normoxia and reduce hyperoxic lung injury in newborn mice. Pediatr Res 67: 591–597
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sun, H., Shi, Y. Letter to the Editor RE: Singh AJ et al. Pediatr Res 67:619–623. Pediatr Res 70, 423 (2011). https://doi.org/10.1203/PDR.0b013e31822d5f00
Issue Date:
DOI: https://doi.org/10.1203/PDR.0b013e31822d5f00