Investigation of the relationship between urinary tract infection and vitamin D levels in children 3-24 months who have used vitamin D routinely for at least 3 months

Investigation of the Relationship Between Urinary Tract Infection And Vitamin D Levels in Children 3-24 Months Who Have Used Vitamin D Routinely For At Least 3 Months Introduction and Purpose Urinary tract infection is the second most common infection in children. Undiagnosed or untreated UTI causes growth retardation, especially in infants. There are many studies in the literature on vitamin D and the immune system. The effects of vitamin D on the immune system are based on two biological bases. The presence of vitamin D receptors in immune-related cells such as lymphocytes, macrophages and dendritic cells and the presence of 1-alpha hydroxylase enzyme, which provides locally active vitamin D synthesis, in these cells. In this study, the relationship between urinary tract infection and 25-(OH) D and 1,25-(OH)2 D3 levels in children aged 3-24 months diagnosed with UTI was investigated. In addition, predisposing factors causing UTI, etiology and treatments of UTI were also evaluated. Materials and Methods Our study was cross-sectional, between September 1, 2021 and September 1, 2022, admitted to Aydın Adnan Menderes University Faculty of Medicine, Department of Pediatrics, diagnosed with urinary tract infection (UTI) (n=57) and healthy individuals of the same age and gender. (n=57) was carried out with a total of 114 children. Demographic data of all children (age - weight - height - dose and duration of vitamin D use - circumcision - urinary USG findings) were recorded in the case follow-up form. In addition, urinary USGs of all children were performed by the same experienced radiologist. When the data in the study were evaluated by statistical analysis, p<0.05 was considered significant. Results In our study, no difference was found between the UTI and control groups in demographic data except for body weight, body weight percentile and head circumference. In addition, no significant difference was found between serum 25-(OH) D (21.9 ng/ml vs. 23.3 ng/ml) and 1.25-(OH)2 D3 (37.6 pg/dl vs. 39.6 pg/dl) levels of the UTI and control groups. (p>0.05). The rate of circumcision in boys in the UTI group was lower than in the healthy group (p<0.05), and the kidney anomalies in the UTI group were significantly higher than in the healthy group (p<0.05). The most common microorganism as a UTI agent was E.Coli, and it was determined that the most preferred antibiotic in the treatment was Amoxicillin-Clavulonate. According to the 25-OH D levels of the subjects included in the study; (12-19.9 ng/ml) inadequate and (≥20 ng/ml) adequately divided into two groups. There was no significant difference between the groups with insufficient and adequate 25-(OH) D levels in terms of demographic data. Conclusion and Discussion In our study, we found that serum 25-(OH) D and 1,25-(OH)2D3 levels in infants who received maintenance vitamin D (400 IU/day) and were found to have UTI were not different from the control group. In conclusion, we think that in infants with normal serum 25-(OH) D and 1,25-(OH)2D3 levels, other causes of UTI may be associated with infection. Although the effects of vitamin D on the immune system are partially known, in our study, no significant difference was found between 25-(OH) D and 1,25-(OH)2D3 levels between the UTI and the healthy group. This suggests that other molecules involved in the immune system pathway may also be effective. In addition, the vitamin D receptor (VDR), which is responsible for maintaining vitamin D epithelial connections, could not be examined in our study, and different mechanisms may also contribute. Although there are many studies in the literature investigating the relationship between 25-(OH)D and UTI, as far as we know, there is no study investigating the relationship between 1,25-(OH)2D3 and UTI. It has been shown in many studies that the elimination of bacterial carriage in the foreskin with circumcision in boys is protective against UTI (10,12,17,18). In our study, we found that the frequency of UTI in circumcised healthy children decreased 12 times. In this context, we think that circumcision is very important in the prevention of UTI in infants. Congenital urinary system anomalies (CAKUT) are among the most important risk factors for urinary tract infection in children (10,34). Urinary system USG was performed in all cases included in our study to investigate urinary system anomalies. In our study, USG anomalies were detected in the right kidney with a rate of 36.8% and in the left kidney at a rate of 59.6% compared to the control group. We think that the presence of kidney anomaly is a serious risk factor for UTI. In our study, the symptoms of UTI, the microorganisms reproduced in the antibiogram and the antibiotics used in the treatment were found to be compatible with the literature. Considering the antibiogram resistance of bacteria in our study; A high rate of resistance was detected against ampicillin and TMP-SMX. As a result, antibiotic resistance in bacteria grown in urine culture is a serious problem. In particular, resistance to antibiotics commonly used in different infections will become more of a problem in the coming years.