Vitamin D and LL-37 in children with pneumonia

Background: Vitamin D is involved in the regulation of about1000 human genes. Recent studies suggest that vitamin D may have other actions outside of its classic functions related to bone and calcium homeostasis. The only human cathelicidin, LL 37, enhances microbial killing against a broad range of respiratory pathogens and has a defined vitamin D- dependent mechanism. Objective: evaluate the association between vitamin D status and plasma LL-37 levels in children with pneumonia. Study design: Forty consecutive children admitted to the chest unit of the Pediatric Department of Zagazig University Hospital with proven diagnosis of pneumonia were included in the study. They were 22 males and 18 females, of ages ranging from 2 to 5 years. In addition, 40 age and sex matched apparently healthy children served as a control group. A verbal consent was obtained from parent(s) of each child before inclusion to the study. All children were subjected to history taking, clinical examination, routine investigations (CBC, CRP and ESR) and chest X-ray done for patients only, as well as determination of serum 25-OH vitamin D and plasma LL-37. Results: The study revealed a highly significant increase of WBCs, ESR and CRP and a highly significant decrease in hemoglobin of patients. Absence of history of sun exposure, increased WBCs counts and low levels of vitamin D and LL-37 were considered as risk factors for pneumonia while site of residence, hemoglobin level and platelets count were not. Both vitamin D and LL-37 were significantly lower in patients than controls (P < 0.001). There were significant positive correlations between vitamin D and LL-37 in studied groups. Conclusion: Appropriate concentrations of vitamin D facilitate the ability of immune system to defend against respiratory tract infections through enhancing LL-37 production. Keywords: vitamin D- LL 37- pneumoniaEgypt J Pediatr Allergy Immunol 2010;8(2):81-8

Effects of vitamin D and the antimicrobial peptide in asthma

Background: Vitamin D modulates a variety of processes and regulatory systems including host defense, inflammation, and immunity. A connection between Vitamin D status and asthma has been considered. Vitamin D mediates innate immunity, particularly through enhanced expression of the human cathelicidin antimicrobial peptide (LL-37). Increased levels of high sensitive-C reactive protein (Hs-CRP) were found to be significantly associated with respiratory function impairment. Objective: to evaluate the relation between serum vitamin D, Hs-CRP and LL-37 levels and asthma. Study design: Thirty children (15 males and 15 females) with proven diagnosis of asthma (ages ranged from 3-13 years) were studied; they attended the pediatric department of Zagazig University Hospital in the year 2011. In addition, 30 age and sex matched apparently healthy children served as a control group. All children were subjected to history taking, clinical examination, laboratory investigations (CBC, CRP, ESR), determination of serum level of 25-hydroxyvitamin D (25 OHD) and plasma LL-37. Results: The study revealed a highly significant decrease in 25 OHD, LL-37 and a highly significant increase in Hs-CRP in children with asthma than in control group. There were a highly significant positive correlation between vitamin D and LL37 in patients' and control groups and a significant negative correlation between both 25OHD and LL37 and Hs-CRP in patients' group. High WBC count (specially neutrophils and lymphocytes), Hs-CRP level and low levels of hemoglobin, 25OHD and LL 37 in patient group were considered risk factors of asthma. Conclusion: Inappropriate concentration of vitamin D decreases the ability of the immune system to defend against infection through lowering LL-37 and elevated Hs-CRP which leads to occurrence and precipitation of asthma.Keywords: Vitamin D- LL-37- asthmaEgypt J Pediatr Allergy Immunol 2012;10(2):101-10

Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality