Objective: To determine the clinical significance of serum 25-hydroxy (OH) vitamin D levels in pediatric patients with multisystem inflammatory syndrome in children (MIS-C) and compare the vitamin D levels of these patients with those patients with Coronavirus disease-2019 (COVID-19) and healthy controls.Methods: This study was designed for pediatric patients aged 1 month to 18 years and conducted between July 14 and December 25, 2021. Fifty-one patients with MIS-C, 57 who were hospitalized with COVID-19, and 60 controls were enrolled in the study. Vitamin D insufficiency was defined as a serum 25 (OH) vitamin D level of less than 20 ng/mL. Severe MIS-C was classified as necessitating intensive care due to cardiovascular instability, the necessity for non-invasive or invasive mechanical ventilation, and/or a diminishing Glasgow coma scale. World Health Organization definition criteria were used to describe the clinical stages of COVID-19 in children and patients were divided into four groups according to the clinical severity of COVID-19: asymptomatic, mild, moderate, and severe/critical. Results: The median serum 25 (OH) vitamin D was 14.6 ng/mL in patients with MIS-C, 16 ng/mL in patients with COVID-19, and 21.1 ng/mL in the control group (p<0.001). Vitamin D insufficiency was present in 74.5% (n=38) of patients with MIS-C, 66.7% (n=38) of patients with COVID-19, and 41.7% (n=25) of the controls (p=0.001). The percentage of four or more affected organ systems was 39.2% in patients with MIS-C. The correlation between the number of affected organ systems and serum 25 (OH) vitamin D levels was evaluated in patients with MIS-C and there was a moderate negative correlation (r=-0.310; p=0.027). A weak negative correlation was found between the severity of COVID-19 and serum 25 (OH) vitamin D (r=-0.320, p=0.015).Conclusion: Vitamin D levels were insufficient in both the MIS-C and COVID groups. Furthermore, vitamin D levels correlated with the number of affected organ systems in MIS-C and the severity of COVID-19.

Background Mannose-binding lectin (MBL) is a member of innate immunity and acts with MASP (MBL-associated serine protease) to activate the lectin pathway of the complement system. MBL gene polymorphisms are associated with susceptibility to infectious diseases. This study investigated whether MBL2 genotype, serum MBL levels, and serum MASP-2 levels affect the course of SARS-CoV-2 infection. Methods and results Pediatric patients diagnosed with COVID-19 by positive real-time polymerase chain reaction (PCR) were included in the study. Single nucleotide polymorphisms in the promoter and exon 1 in the MBL2 gene (rs11003125, rs7096206, rs1800450, rs1800451, rs5030737) were identified by a PCR and restriction fragment length polymorphisms analysis. Serum MBL and MASP-2 levels were measured by ELISA. COVID-19 patients were divided into asymptomatic and symptomatic. Variables were compared between these two groups. A total of 100 children were included in the study. The mean age of the patients was 130 ± 67.2 months. Of the patients, 68 (68%) were symptomatic, and 32 (32%) were asymptomatic. The polymorphisms in the − 221nt and − 550nt promoter regions did not differ between groups (p > 0.05). All codon 52 and codon 57 genotypes were determined as wild-type AA. AB genotypes were found 45.6% in symptomatic patients while 23.5% in asymptomatics. Moreover, BB genotype was detected 9.4% in symptomatic and 6.3% in asymptomatic patients (p < 0.001). B allele was more frequent in symptomatic patients (46.3%) compared to asymptomatic patients (10.9%). (p < 0.001). Serum MBL and MASP-2 levels did not differ statistically between the groups (p = 0.295, p = 0.073). Conclusion These findings suggest that codon 54 polymorphism in the MBL2 gene exon-1 region can be associated with the symptomatic course of COVID-19.

Objective: This study aimed to determine the epidemiology of Acinetobacter species in the last 5 years, the clinical diseases caused by the pathogen, the possible risk factors for infection, and the resistance pattern of the microorganism in our quaternary-care hospital. Materials and Methods: In this retrospective cohort study, 67 pediatric cases infected with Acinetobacter species in our hospital between January 2017 and December 2021 were analyzed. Demographic characteristics and clinical and laboratory findings were analyzed. Results: In pediatric patients infected with Acinetobacter spp., the median age was 36 (7-114) months, and 64.2% (n = 43) were female. Acinetobacter baumannii was grown in the cultures of 31 (46.3%) cases. When the type of infection was examined, 31 (46.3%) cases were urinary tract infections, and 29 (43.3%) cases were bloodstream infections. Extensively drug-resistant, pandrug-resistant, and multidrug-resistant A. baumannii were found in 10 (14.9%), 3 (4.5%), and 2 (3%) cases, respectively. Health-care-associated infections were found to have a significant rate of Acinetobacter resistance (P = .002). Significant antimicrobial resistance was detected in Acinetobacter-infected cases with intensive care hospitalization within the last month and carbapenem use in the previous 3 months (P < .001, both). Conclusion: It is necessary to act in accordance with the infection prevention and control program to reduce the incidence of health-care-associated infections with Acinetobacter species and to prevent infection with highly resistant strains. Due to health-care-associated infections and factors contributing to the increase in Acinetobacter resistance, we believe this study will help clinicians to be more cautious in the use of carbapenems. Cite this article as: Elvan-Tüz A, Tekin D, Ekemen-Keleş Y, et al. Clinical reflections of acinetobacter infections in children in a quaternary-care hospital: A five-year single-center experience. Turk Arch Pediatr. 2024;59(1):38-42.

Background: Coronavirus disease 2019 (COVID‐19) in children is milder than in adults. Household virus exposure may affect clinical severity. We aimed to determine the household contact history of patients and its influence on the clinical stage. Methods: One hundred and seventy‐three pediatric patients with COVID‐19 as diagnosed with positive real‐time polymerase chain reaction for severe acute respiratory syndrome coronavirus‐2 aged 1 month to 18 years were included. Demographic data, laboratory and clinical findings, and the history of household contact of the patients were obtained. They were classified according to their clinical stage as mild or moderate‐severe. Results: Sixty patients (34.7%) were asymptomatic, and 113 were symptomatic (65.3%). Of the 173 patients, 138 (79.8%) had at least one family member in the household who was diagnosed as having COVID‐19. Hemoglobin, absolute neutrophil count, and absolute neutrophil count /absolute lymphocyte count ratio decreased significantly in patients with household contact. The presence of a household contact did not have a significant effect on the presence of symptoms, clinical course, age, and the sex of the patients. The need for hospitalization was less in the group that had household contact. Being 0–12 months, being female, and being a patient without household contact were independent factors associated with higher hospitalization ratios in logistic regression analysis. Conclusions: In this study, we found that household contact history did not significantly affect presenting symptoms and clinical course. We detected the rate of hospitalization to be less in the group with only household contact.