Evaluation of vitamin D and related factors in childreen with recurrent lung infections

Recurrent Pneumonia is the occurrence of at least two pneumonia attacks in the past year, or at least three pneumonia episodes with radiological improvements throughout the life of the patient. Significant studies have been conducted on the important tasks of vitamin D in many extraskeletal tissues, especially in the immune system. Vitamin D shows its effects on the immune system through molecules called antimicrobial peptide (AMP). In this study, the relationship between recurrent pneumonia and vitamin D and beta defensin, cathelicidin levels were investigated. Fifty children diagnosed with recurrent pneumonia of 6 months-72 months who were admitted to Dicle University Medical Faculty Pediatric Pulmonary Diseases outpatient clinic between May 1, 2018 and September 1, 2018 and 86 healthy children without any chronic diseases admitted to other outpatient clinics with other complaints during the same period were included in the study. Venous blood samples taken from 136 patients were stored at -80 degrees for the measurement of the parameters of Vitamin D, defensin and cathelicidin after centrifuged at 4000 rpm for 5 minutes in Dicle University Faculty of Medicine Biochemistry laboratory. Samples were then thawed and washed with a Biotek brand ELX 50 model washing machine and evaluated with the Biotek brand ELX800 Elisa reading device. Fiftyeight percent of the patients in the case group of the study were female and 42% were male. 41.9% of the control group were female and 58.1% were male. The mean age was 31.14±21.9 months in the case group, and 35.88±22.5 months in the control group. Of the patients in the case group, the median value of serum vitamin D levels was 580,10 nmol /L, the median value of serum cathelicidine values was 9.8 ng/mL and the median value of serum defensin levels was 12.02 ng/mL. Of the control group, the median value of serum vitamin D values was 484,376 nmol/L, the median value of serum cathelicidine levels was 15,59 ng/mL and the median VII value of serum defensin levels was measured as 7,79 ng/mL. Serum vitamin D and serum defensin levels were significantly higher in the case group than the control group. There was no significant difference between the groups in terms of serum cathelicidin value. These three parameters were inversely correlated with the age of the cases while there was a positive correlation between serum vitamin D, serum defensin and serum cathelicidin levels in both the case and the control group. In our study, a significant relationship was found between the incidence of pneumonia and the familial atopy history among the environmental factors evaluated, and the incidence of recurrent pneumonia in children of families with a history of atopy was found as high. The season in which the study was conducted coincided with the summer months resulted in high relatively levels of vitamin D in both groups and this was one of the limitations of the study. The studies which will be held in longer term will provide more accurate results. The benefits of reducing the frequency and severity of low respiratuary tract infections (LRTIs) in the development of lower respiratory tract infections, especially pneumonia, should be investigated furtherly.Vitamin D replacement is an important application of preventive medicine and with proper applications, the development of both a healthy skeletal tissue and healthy immune system can be achieved in children. Vitamin D is an important prognostic factor and the benefit of vitamin D replacement and support for nutrition to prevent attacks should be investigated. In addition, at the present time when bacterial resistance to classical antibiotics is high, the effects of antimicrobial peptides with broad activity spectra on the pathogens involved in the pathogenesis of pneumonia and other LRTI are important. We need enlarged and detailed studies on these AMPs. Key words: Pneumonia, vitamin D, beta defensin, cathelicidine, immun system