The vitamin D grey areas in pediatric primary care. Very low serum 25-hydroxyvitamin D levels in asymptomatic children living in northeastern Italy
© Mazzoleni et al; licensee BioMed Central Ltd. 2012
Received: 24 March 2012
Accepted: 18 April 2012
Published: 18 April 2012
The principal questions about the vitamin D topic are far to be resolved: in which children 25-hydroxyvitamin D blood testing is appropriate and how much cholecalciferol should be given in the absence of the test? Analyzing vitamin D status in a group of children cared by a "family pediatrician" in northeastern Italy we noted a high incidence of deficiency in asymptomatic preschool children without risk factors. As routine vitamin D testing is not recommended in the average risk population the supplementation with cholecalciferol represents a "grey area" mostly in pediatric primary care.
Keywords25-Hydroxyvitamin D vitamin D cholecalciferol deficiency insufficiency supplementation
we read with interest the article by Bener and Hoffmann on the incidence of nutritional rickets in a sun rich country like Qatar , where decreased vitamin D was a major risk factor. Hypovitaminosis D is highly prevalent in children throughout the world [2, 3] but it is still not clear what is the best practice in pediatric primary care settings. Michael Holick, a recognized expert on the topic, has stated that "there is no need to measure everybody's blood 25-hydroxyvitamin D" [25(OH)D] and that only patients with particular diseases should be screened for vitamin D insufficiency/deficiency . Although the literature has shown that patients with deficiency are much less frequent than those with insufficiency, it is also remarkable that vitamin D deficiency is often subclinical and depending on local situations; for example it may be associated with overweight  or underweight . To our knowledge there are only a few studies on children living in northeastern Italy [6–8]: they have been conducted retrospectively  or examining patients afferent to a Pediatric Department  or asthmatic . On this basis an analysis of vitamin D status was prospectively conducted in children cared by a "family pediatrician" in a rural area near Padua (45° N latitude). In 65 patients the vitamin D test was included in exams ordered for different reasons (suspected anemia, fatigue, poor growth, etc.) between November 2010 and June 2011. Results were retrieved from 58 children (age range 1.1-15.3 years, median age 6.75 years). Serum 25(OH)D was dosed by chemiluminescence; the laboratory normal range was 75-250 nmol/l (30-99 ng/ml); insufficiency was defined as 25-74 nmol/l (10-29 ng/ml), deficiency as < 25 nmol/l (< 10 ng/ml).
Most of the children (77%) had low serum 25(OH)D levels: 38 of them (66% of all patients) had an insufficiency and 7 (12%) had a deficiency. Moreover, 29 children (50%) had 25(OH)D < 50 nmol/l (< 20 ng/ml) that is the cut-off recently suggested to diagnose vitamin D deficiency [5, 9].
< 25 nmol/l
< 50 nmol/l
< 10 ng/ml
< 20 ng/ml
Holick has suggested that "it would be much more cost-effective to implement a vitamin D supplementation program for all children and adults"  but the question now is how much vitamin D should be given. If 400 IU cholecalciferol per day may be sufficient in the first year of life , much more is needed in older children, assuming that most of them have less or much less than the minimum desirable . Moreover, recommended doses of 600 IU per day  probably offer no advantage to children with 25(OH)D < 25 nmol/l (< 10 ng/ml) . Although authoritative guidelines state that routine vitamin D testing is not warranted in the average risk population, the Holick's D-lemma  is far from being resolved.
- Bener A, Hoffmann GF: Nutritional Rickets among Children in a Sun Rich Country. Int J Pediatr Endocrinol. 2010, 2010: 410502-10.1186/1687-9856-2010-410502. Epub 2010 Oct 27PubMed CentralView ArticlePubMedGoogle Scholar
- Mansbach M, Ginde AA, Camargo CA: Serum 25-Hydroxyvitamin D levels among US children aged 1 to 11 years: do children need more vitamin D?. Pediatrics. 2009, 124: 1404-1410. 10.1542/peds.2008-2041.PubMed CentralView ArticlePubMedGoogle Scholar
- Rathi N, Rathi A: Vitamin D and child health in the 21st century. Indian Pediatr. 2011, 48: 619-625. 10.1007/s13312-011-0107-9.View ArticlePubMedGoogle Scholar
- Holick MF: The D-lemma: To screen or not to screen for 25-Hydroxyvitamin D concentrations. Clin Chem. 2010, 56: 729-731. 10.1373/clinchem.2009.139253.View ArticlePubMedGoogle Scholar
- Saintonge S, Bang H, Gerber LM: Implications of a new definition of vitamin D deficiency in a multiracial US adolescent population: the National Health and Nutrition Survey III. Pediatrics. 2009, 123: 797-803. 10.1542/peds.2008-1195.View ArticlePubMedGoogle Scholar
- Lippi G, Montagnana M, Targher G: Vitamin D deficiency among Italian children [letter]. CMAJ. 2007, 177: 1529-1530.PubMed CentralView ArticlePubMedGoogle Scholar
- Marrone G, Rosso I, Moretti R, Valent F, Romanello C: Is vitamin D status known among children living in Northern Italy?. Eur J Nutr. 2012, 51: 143-149. 10.1007/s00394-011-0200-9. [Epub 2011 May 4]View ArticlePubMedGoogle Scholar
- Chinellato I, Piazza M, Sandri M, Peroni D, Piacentini G, Boner AL: Vitamin D serum levels and markers of asthma control in Italian children. J Pediatr. 2011, 158: 437-441. 10.1016/j.jpeds.2010.08.043. Epub 2010 Sep 26View ArticlePubMedGoogle Scholar
- Holick MF: Vitamin D deficiency. N Engl J Med. 2007, 357: 266-281. 10.1056/NEJMra070553.View ArticlePubMedGoogle Scholar
- Mutlu GY, Kusdal Y, Ozsu E, Cizmecioglu FM, Hatun S: Prevention of Vitamin D deficiency in infancy: daily 400 IU vitamin D is sufficient. Int J Pediatr Endocrinol. 2011, 2011: 4-10.1186/1687-9856-2011-4. Epub 2011 Jun 28PubMed CentralView ArticlePubMedGoogle Scholar
- Vieth R: Why the minimum desirable serum 25-hydroxyvitamin D level should be 75 nmol/L (30 ng/ml). Best Pract Res Clin Endocrinol Metab. 2011, 25: 681-691. 10.1016/j.beem.2011.06.009.View ArticlePubMedGoogle Scholar
- Abrams SA: Dietary Guidelines for Calcium and Vitamin D: A New Era. Pediatrics. 2011, 127: 566-568. 10.1542/peds.2010-3576.View ArticlePubMedGoogle Scholar
- Heaney RP, Davies KM, Chen TC, Holick MF, Barger-Lux MJ: Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. Am J Clin Nutr. 2003, 77: 204-210.PubMedGoogle Scholar
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