The effect of vitamin d testing of positive results and clinical decisions in an univercity hospital

AİM: Vitamin D deficiency causes some clinical symptoms on bone and muscle tissues. Serum 25-OH Vitamin D deficiency is diagnosed with serum levels below 20 ng / ml (50 nmol / L) (1). The serum 25-OH Vitamin D test is used too much in daily practice and the positive test result seems to be quite high. Apart from the risk groups, many of the results obtained as low can be false positives. Because there is not enough standardization work for our country in the measurement of serum 25-OH vitamin D, internationally accepted limit value is not determined, seasonal serum 25-OH Vitamin D level can be changed and when serum 25-OH Vitamin D level is controlled, serum Ca-PTH levels should be evaluated together (2-3). Vitamin-D supplementation is usually done without consideration of such situations. The aim of this study is to determine the effect of test results on clinical decisions, taking into account the preliminary probabilities of clinical vitamin D deficiency with a positive test frequency in all vitamin serum 25-OH vit D assays performed in a university hospital in 2016 and indications for testing. Preliminary information: Vitamin D is a hormone that can be synthesized in the body as a result of a number of biochemical reactions, although it can be obtained with a group of vitamins and vitamins. Vitamin D, which is an anterior hormone, is activated by ultraviolet rays. Therefore, the activation of vitamin D can vary depending on the person's level of sunbathing, the season in which he lives, and the characteristics of the geographical region in which he is living. The amount of vitamin D taken with food is not enough to meet daily needs (8). Vitamin D, which is synthesized from cholesterol in the body, can be stored in the form of previtamin for several months in the liver. Kanda 1,25-OH vit D is present for several hours while 25-OH vit D can remain for 15-20 days (4,5,6,7,8). The best indicator of vitamin D levels is the 25-OH vit D test. This test does not have enough standardization work for our country. Significant differences can occur even among laboratory measurement methods (4). Serum vitamin D levels in the absence of clinical symptoms lead to more misleading results. Vitamin D is a hormone that creates a danger of intoxication like vitamin A. Vitamin D intoxication can be seen in newborns when vitamin D is used 40,000 IU a day for 1-4 months, and for adults, 100,000 IU a day for a few months (5). Clinical symptoms should be assessed very well when considering Vitamin D deficiency, diagnosing vitamin D, or when taking vitamin D supplements. The false positives in the test should always be kept in mind, and if possible, careful attention should be paid to the diagnostic verification with the Ca, PTH, P, ALP test (2-3-6-7). Materials and methods: Our work is a descriptive research. All serum 25-OH vit D tests performed between January 1, 2016 and December 31, 2016 at Adnan Menderes University Hospital were evaluated. It has been found that about 16 thousand tests have been made in the preliminary investigation. The data will be obtained electronically from the hospital records and all information related to the test request will be processed into the database created. More than one test application on the same person was taken into account. Within a year, the clinical files of 800 patients to be randomly selected from all the patients who were asked to be tested were accessed and all data related to vitamin D were recorded and evaluated. Administrative permission from the hospital administration and approval from the Ethics Committee of the Faculty of Medicine were taken for the study. The data were statistically evaluated by being processed in a statistical package program.