School-aged children and their health conditions, in particular, deficient conditions are not less note worthy than in younger children, while the recognition of present low vitamin D provision in children of all age groups has not still resulted in implementation of mass prophylaxis of hypovitaminosis D. There are several factors on which blood concentration of 25 (OH) D-calcidiol-depends. However, it is evident that among numerous factors we should orient on several most significant and develop correction scheme for the deficient condition in every region. Aim: to assess vitamin D levels in adolescents residing in Moscow, to correct their calcidiol status based on a baseline blood concentration of the transport metabolite. Materials and methods: 769 adolescents aged 11-18 years were examined and their blood concentration of 25 (OH) D was determined. Then, 218 patients were randomized to 2 groups: the treatment group received food supplement "Minisun ® Vitamin D 3 " in tablets, the control group received placebo. Cholecalciferol dosage was prescribed depending on the baseline calcidiol level in patients. The study continued for 6 months, after that blood was re-withdrawn for calcidiol level. Results: low calcidiol provision was observed among school children: median 25 (ОН) D was 16.3 [11.4-20.8] ng/mL, only 5.2% of patients had normal blood concentration of calcidiol. There-examination showed significant differences in vitamin D status in the treatment and control group, in the meantime, during cholecalciferol supplementation, median 25 (OH) D in patients of the treatment group was increased from 16.2 [12.25-19.3] ng/mL to 24.2 [21.05-26.4] ng/mL (p < 0.001). Conclusions: the larger part of child population-70.6% has 25 (OH) D concentration < 20 ng/mL, cholecalciferol doses used in the study allow eliminating calcidiol deficiency and overcome the boundary of 20 ng/mL, but for normalization of vitamin D status in blood of adolescents residing in Moscow higher dosages shall be used which is to be confirmed by further studies.

Background Microscopic colitis (MC) is a chronic inflammatory disease of the colon presenting with watery diarrhoea. It encompasses two entities, namely lymphocytic colitis (LC) and collagenous colitis (CC). Population-based epidemiologic data the frequency and natural history of microscopic colitis are scarce. We evaluated the clinical presentation at diagnosis, incidence and prevalence of MC in Cantons of Vaud and Fribourg, Switzerland. Methods Cantons of Vaud and Fribourg lie in the French-speaking, Western part of Switzerland. As of 12/2017, both cantons together had a population of 1,109,230 inhabitants. We contacted all Pathology institutes (n = 6) in both cantons in order to identify patients that have been diagnosed with microscopic colitis. We then performed a chart review in all adult and paediatric gastroenterology practices in order to identify MC patients and to assess the incidence, prevalence, their clinical, endoscopic, and histological characteristics as well as natural history. Results Out of 252 patients, a total of 218 fulfilled the diagnostic criteria for MC, whereof 123 had LC and 95 had CC. Age at first diagnosis of MC was 63.2 ± 14.3 years (62.8 ± 14.3 for LC, 63.7 ± 14.4 years) and median diagnostic delay was 1.1 ± 3.1 years. Symptoms leading to MC diagnosis were diarrhoea (100%), abdominal pain (31.7%), weight loss (31.2%), bloating (20.6%), fatigue (9.6%), and nausea/vomiting (3.2%). The following risk factors were found in MC patients: statins (27.1%), aspirine (23.4%), proton pump inhibitors (22.5%), serotonine reuptake inhibitors (22.5%), smoking (20.2%), non steroidal anti-inflammatory drugs (14.2%), and neuroleptics (4.1%). Median exposure time to risk factors was 55 months (IQR 33–78, range 1–280 months). Associated auto-immune diseases (celiac disease, type 1 diabetes, autoimmune gastritis, autoimmune thyroiditis, rheumatoid arthritis) were found in 14 patients (6.4%). No patient was diagnosed with MC prior to 1994. Incidence of MC significantly increased from 0.36/100,000 inhabitants in 1994–1997 to 6.85/100,000 inhabitants in 2017 (p = 0.025). The cumulative prevalence of MC, LC, and CC in 2017 was 19.65/100,000, 11.09/100,000, and 8.56/100,000, respectively. Conclusion The incidence and cumulative prevalence of MC shows a steady increase in an indicator region of roughly 1 million inhabitants in French speaking part of Switzerland.