5th Intercontinental Cooperative ITP Study Group (ICIS) expert meeting in Flüeli-Ranft, Switzerland, September 2015.

The primary objective of the study was to assess the vitamin D (VD) status of patients suffering from ITP. Children from the case cohort (total 21) were recruited from chronic ITP patients (followed as outpatients) and newly diagnosed ITP (prospective study) patients. VD deficiency (values <75 nmol/L) was detected in 11 patients with newly diagnosed ITP, and seven patients with chronic ITP. Only three patients with newly diagnosed, and none with chronic ITP had normal VD values. Newly diagnosed ITP patients had statistically significantly higher values (P <.044) of VD than the patients with chronic type of ITP. Platelets values did not follow VD level. VD deficiency is very common in children with either newly diagnosed or chronic ITP form. Therefore there is a utility supplementing VD in these patients. To investigate the role of VD as an immune modulating drug for patients with ITP, a prospective randomized placebo-controlled trial needs to be performed.