Association between mannose binding lectin gene polymorphisms and clinical severity of COVID-19 in children.

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.

A prospective long-term evaluation of the ocular findings of children followed with the diagnosis of multisystem inflammatory syndrome (long-term evaluation of ocular findings following MIS-C).

BACKGROUND/OBJECTIVES: The most frequently reported ocular finding in the acute phase of the multisystem inflammatory syndrome in children (MIS-C), is conjunctivitis. More rarely, punctuate epitheliopathy, anterior uveitis and optic disc oedema can be seen. We aimed to investigate the acute and long-term ocular effects of MIS-C. SUBJECTS/METHODS: Cases aged 1 month to 18 years who were diagnosed with MIS-C between January 2022 and June 2022 in the Department of Pediatric Infectious Diseases in our hospital were included in the study. Ophthalmological examinations were performed immediately after diagnosis, at one month, three months, and six months. RESULTS: Males consisted of 64.7% of the 34 cases included in the study and the mean age was 8.68 ± 4.32 years (min-max:2-17). In the first examination, conjunctivitis was observed in 6 (17.6%), punctuate epitheliopathy in 4 (11.7%), and subconjunctival haemorrhage in 3 (8.8%) patients. Two patients (5.8%) had optic disc oedema. No pathological anterior or posterior segment findings were observed in the sixth-month examination. The relationship between subconjunctival haemorrhage and intensive care hospitalisation was statistically significant (p = 0.014). Also, all patients with subconjunctival haemorrhage were clinically classified as severe MIS-C (p = 0.002). CONCLUSION: Although pathological ocular findings were observed in the acute phase of the disease, all of them were found to be improved at the sixth-month follow-up. The most striking finding of our study is that cases with subconjunctival haemorrhage were clinically more severe, and all patients needed intensive care. This study may be informative in establishing ocular follow-up protocols that are expected to be carried out in the acute period and in the follow-up of these patients.

The diversity in the clinical features of children hospitalized with COVID-19 during the nonvariant, Alpha (B.1.1.7), Delta (B.1.617.2), and Omicron (B.1.1.529) variant periods of SARS CoV-2: Caution for neurological symptoms in Omicron variant.

Since the COVID-19 pandemic began, various severe acute respiratory syndrome coronavirus 2 variants have been identified with different characteristics than the nonvariant strain. We retrospectively evaluated the demographic and clinical differences in the cohort of hospitalized COVID-19 children (1 month-18 years old) between March 11, 2020, and September 31, 2022, by the time the variants identified in our country predominate. Bonferroni post hoc analysis was performed to compare the differences between the periods. Of the 283 children in this study, 142 (50.2%) were females. The median age was 36 (interquartile range [IQR]: 7-132) months. Sixty-three (22.2%) patients were hospitalized in the nonvariant period, 24 (8.5%) in the Alpha period, 93 (32.9%) in the Delta period, and 103 (36.4%) in the Omicron period. Fever was the most common symptom in all groups, with no statistically significant differences (p = 0.25). In the Omicron period, respiratory and gastrointestinal symptoms decreased, and neurological symptoms increased significantly compared to other periods: [respiratory symptoms; nonvariant (65.1%) vs. Omicron (41.7%), (p = 0.024)], [gastrointestinal symptoms; Delta (41.9%) vs. Omicron (22.3%), (p = 0.018), [neurological symptoms; Delta (14.5%) vs. Omicron (31.1%), (p = 0.03]. Altered mental status and seizures were more common during the Omicron period compared to the pre-Omicron (nonvariant, Alpha, and Delta) period (p = 0.017 and p = 0.005, respectively). Although the main symptoms in children with COVID-19 were fever and respiratory symptoms, an increase in severe neurological manifestations was seen throughout the Omicron variant period.

Can Serum 25-Hydroxy Vitamin D Levels Predict the Severity of Multisystem Inflammatory Syndrome in Children and COVID-19?

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.

Differentiating abdominal pain due to COVID-19 associated multisystem inflammatory syndrome from children with acute appendicitis: a score system.

PURPOSE: Differentiating abdominal pain due to coronavirus disease (COVID-19)-associated multisystem inflammatory syndrome (MIS-C) in children with acute appendicitis (AA) can cause diagnostic dilemmas. This study aimed to evaluate the efficacy of a previously described scoring system and improve its diagnostic ability in differentiating between these diseases. METHODS: This study was conducted between March 2020 and January 2022. Patients who had MIS-C with gastrointestinal system (GIS) involvement and patients who underwent surgery for appendicitis were included. First, all patients were evaluated using the new scoring system (NSS). The groups were compared by adding new MISC-specific parameters to NSS. The scoring system was evaluated using propensity score matching (PSM). RESULTS: A total of 35 patients with abdominal pain due to GIS involvement in MIS-C (group A) and 37 patients with AA who had ALT, PRC, and D-dimer results at their first admission (group B) were included in the study. The mean age of patients in group A was lower than that of patients in group B (p < 0.001). False NSS positivity was found in 45.7% of the patients with MIS-C. Lymphocyte (p = 0.021) and platelet counts (p = 0.036) were significantly lower in the blood count and serum D-dimer (p = 0.034), C-reactive protein (CRP) (p < 0.001), and procalcitonin (p < 0.001) were significantly higher in the MIS-C group. We created a scoring system called the Appendicitis-MISC Score (AMS) using the NSS and new parameters. The sensitivity and specificity of AMS diagnostic scores were 91.9% and 80%, respectively. CONCLUSION: MIS-C with GIS involvement may present as acute abdomen. It is difficult to differentiate this condition from acute appendicitis. AMS has been shown to be useful for this differentiation.

Serum Amyloid A Levels and Severity of COVID-19 in Children.

OBJECTIVE: The aim of this study was to determine the availability of serum amyloid A (SAA) in the diagnosis of coronavirus disease 2019 (COVID-19), to asses disease severity and to predict hospitalization status. METHODS: Between March, 2020 and March, 2021, a total of 80 children (40 cases with COVID-19 and 40 cases in healthy group) were included in this study. Patients were divided into two groups (mild and moderate/severe) to evaluate SAA levels in terms of clinical severity and also hospitalization status. RESULTS: Comparisons between the two groups revealed that median SAA values were significantly higher in children with COVID-19 than in their healthy peers (21.45vs3.05 mg/L, P=0.002). There was no significant difference in the median serum SAA levels between mild and moderate/severe clinical disease (P=0.837). The SAA difference between the two groups with regards to hospitalization was not statistically significant (P=0.098). CONCLUSIONS: Although SAA level was found to be higher in children with COVID 19 compared to healthy controls, the sensitivity of SAA for the disease was found to be low. In addition, there was no difference between the groups in terms of clinical severity.

Does the Thymus Index Predict COVID-19 Severity?

BACKGROUND: The COVID-19 (coronavirus disease 2019) pandemic is a global health emergency that is straining health care resources. Identifying patients likely to experience severe illness would allow more targeted use of resources. This study aimed to investigate the association between the thymus index (TI) on thorax computed tomography (CT) and prognosis in patients with COVID-19. METHODS: A multicenter, cross-sectional, retrospective study was conducted between March 17 and June 30, 2020, in patients with confirmed COVID-19. The patients' clinical history and laboratory data were collected after receiving a signed consent form. Four experienced radiologists who were blinded to each other and patient data performed image evaluation. The appearance of the thymus was assessed in each patient using 2 published systems, including the TI and thymic morphology. Exclusion criteria were lack of initial diagnostic thoracic CT, previous sternotomy, pregnancy, and inappropriate images for thymic evaluation. A total of 2588 patients with confirmed COVID-19 and 1231 of these with appropriate thoracic CT imaging were included. Multivariable analysis was performed to predict the risk of severe disease and mortality. RESULTS: The median age was 45 (interquartile range, 33-58) years; 52.2% were male. Two hundred forty-nine (20.2%) patients had severe disease, and 60 (4.9%) patients died. Thymus index was significantly associated with mortality and severe disease (odds ratios, 0.289 [95% confidence interval, 0.141-0.588; P = 0.001]; and 0.266 [95% confidence interval, 0.075-0.932; P = 0.038]), respectively. Perithymic lymphadenopathy on CT imaging had a significantly strong association with grades of TI in patients with severe disease and death ( V = 0.413 P = 0.017; and V = 0.261 P = 0.002, respectively). A morphologically assessable thymus increased the probability of survival by 17-fold and the absence of severe disease by 12-fold. CONCLUSION: Assessment of the thymus in patients with COVID-19 may provide useful prognostic data for both disease severity and mortality.

Coronavirus disease 2019 in healthy children: What is the effect of household contact?

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.

Seasonal coronaviruses infections in children: do they always cause mild illness?

BACKGROUND: Human coronaviruses (HCoVs) cause a comprehensive clinic ranging from asymptomatic course to pneumonia. We aimed to describe the HCoV infections in children to determine the clinical status and coinfection effects in a five-year retrospective surveillance study. The primary outcome was admission to the intensive care unit (ICU) and the secondary outcome was the need of high oxygen support. METHODS: Between September 2015 and November 2020, all patients whose reverse transcription polymerase chain reaction (RT-PCR) tests were positive were determined and patients with HCoVs were included in the study. Demographical characteristics, underlying chronic diseases, clinical diagnosis, laboratory data, subtypes of HCoVs, radiological findings, treatments, hospitalization, and ICU admission were analyzed. RESULTS: Of the 2606 children, the overall respiratory tract virus detection rate was 82.4%. Among these, 98 cases were HCoVs positive and of these 80 (81.6%) were under five years of age and most of the patients were admitted to the hospital in spring and 70% were a mixed infection with other respiratory viruses. Since lower respiratory tract infections are more common in HCoV coinfections, a significant difference was found in clinical diagnosis (p < 0.001). The presence of hypoxia (p=0.003) and underlying disease (p=0.004) were found to be significantly more common in patients admitted to the ICU. The presence of hypoxia, infiltration on chest X-ray, and elevated C-reactive protein levels were more frequently determined in patients who received high oxygen support (p=0.001, p=0.036, p=0.004, respectively). CONCLUSIONS: Clinical findings may be more severe if HCoVs, which generally cause mild respiratory disease, are coinfected with another viral agent.

Evaluation of Depression, Anxiety, and Sleep Quality in Children Diagnosed With COVID-19.

ABSTRACT: COVID-19 has affected individuals of all age groups, both physically and mentally. We aimed to determine anxiety and depression in children diagnosed with COVID-19. Fifty children aged 8 to 18 years diagnosed with COVID-19 were included in the study. The children were evaluated the revised Child Anxiety and Depression Scale, STAI form TX-I (state anxiety inventory), and STAI form TX-II (trait anxiety inventory). Child Sleep Habits Questionnaire was applied for one of the parents according to three different periods. The periods were established as before the pandemic, during the illness-quarantine process, and after the quarantine. We observed the highest scores for depression-anxiety and the poorest sleep quality during the quarantine period. The scores for depression-anxiety were lower, and sleep quality scores were higher in the prepandemic period compared with after the quarantine period. Measures should be taken to protect mental health for children with COVID-19.

Are Thyroid Functions Affected in Multisystem Inflammatory Syndrome in Children?

Objective: Multisystem inflammatory syndrome in children (MIS-C), associated with Coronavirus disease-2019, is defined as the presence of documented fever, inflammation, and at least two signs of multisystem involvement and lack of an alternative microbial diagnosis in children who have recent or current Severe acute respiratory syndrome-Coronavirus-2 infection or exposure. In this study, we evaluated thyroid function tests in pediatric cases with MIS-C in order to understand how the hypothalamus-pituitary-thyroid axis was affected and to examine the relationship between disease severity and thyroid function. Methods: This case-control study was conducted between January 2021 and September 2021. The patient group consisted of 36 MIS-C cases, the control group included 72 healthy children. Demographic features, clinical findings, inflammatory markers, thyroid function tests, and thyroid antibody levels in cases of MIS-C were recorded. Thyroid function tests were recorded in the healthy control group. Results: When MIS-C and healthy control groups were compared, free triiodothyronine (fT3) level was lower in MIS-C cases, while free thyroxine (fT4) level was found to be lower in the healthy group (p<0.001, p=0.001, respectively). Although the fT4 level was significantly lower in controls, no significant difference was found compared with the age-appropriate reference intervals (p=0.318). When MIS-C cases were stratified by intensive care requirement, fT3 levels were also lower in those admitted to intensive care and also in those who received steroid treatment (p=0.043, p<0.001, respectively). Conclusion: Since the endocrine system critically coordinates and regulates important metabolic and biochemical pathways, investigation of endocrine function in MIS-C may be beneficial. These results show an association between low fT3 levels and both diagnosis of MIS-C and requirement for intensive care. Further studies are needed to predict the prognosis and develop a long-term follow-up management plan.

Evaluation of vaccination status of health care workers for recommended vaccines and their acceptance of SARS-CoV-2 vaccines.

INTRODUCTION: Health care workers (HCWs) are disproportionately exposed to infectious diseases and play a role in nosocomial transmission, making them a key demographic for vaccination. HCW vaccination rates are not optimal in many countries; hence, compulsory vaccination policies have been implemented in some countries. Although these policies are effective and necessary under certain conditions, resolving HCWs' hesitancies and misconceptions about vaccines is crucial. HCWs have the advantage of direct contact with patients; hence, they can respond to safety concerns, explain the benefits of vaccination, and counter antivaccine campaigns that escalate during pandemics, as has been observed with COVID-19. METHOD: A short survey was carried out in May-June 2020 on the vaccination status of HCWs working with pediatric patients with COVID-19. The survey inquired about their vaccination status (mumps/measles/rubella [MMR], varicella, influenza, and diphtheria/tetanus [dT]) and willingness to receive hypothetical future COVID-19 vaccines. The respondents were grouped according to gender, age, occupation, and region. RESULTS: In total, 4927 HCWs responded to the survey. Most were young, healthy adults. The overall vaccination rates were 57.8% for dT in the past 10 years, 44.5% for MMR, 33.2% for varicella, and 13.5% for influenza. Vaccination rates were the highest among physicians. The majority of HCWs (81%) stated that they would be willing to receive COVID-19 vaccines. CONCLUSION: Although vaccination rates for well-established vaccines were low, a majority of HCWs were willing to receive COVID-19 vaccines when available. Education and administrative trust should be enhanced to increase vaccination rates among HCWs.

Influenza is more severe than our newest enemy (COVID-19) in hospitalized children: Experience from a tertiary center.

Understanding differences in terms of clinical phenotypes and outcomes of coronavirus disease 2019 (COVID-19) compared with influenza is vital to optimizing the management of patients and planning healthcare. Herein, we aimed to investigate the clinical differences and outcomes in hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza. We performed a retrospective study of hospitalized children who were positive for SARS-CoV-2 between March 2020 and March 2021 and for influenza between January 2016 and February 2020 in respiratory samples. The primary outcome of this study was pediatric intensive care unit (PICU) admission, and the secondary outcome was the need for respiratory support. A total of 74 patients with influenza and 71 who were positive for SARS-CoV-2 were included. The distribution among the sexes was similar, but patients with COVID-19 were older than patients with influenza (96 vs. 12, p < 0.001). In terms of underlying chronic diseases, the frequency was 26.7% in the COVID-19 group and 54% in the influenza group (p = 0.001). The comparison of symptoms revealed that fatigue, headache, nausea, vomiting, and abdominal pain occurred more frequently with COVID-19 (for all p < 0.05) and runny nose with influenza (p = 0.002). The frequency of admission to the PICU was relatively higher (18.9%) in the influenza group than with COVID-19 (2.8%) with a significant ratio (p = 0.001), secondary bacterial infections were observed more frequently in the influenza group (20.2% vs. 4.2%, p = 0.003). Some 88.7% of patients with COVID-19 did not need respiratory support, whereas 59.4% of patients with influenza did require respiratory support (p < 0.001). This study noted that influenza caused more frequent admissions to the PICU and a greater need for respiratory support in hospitalized pediatric patients than COVID-19.

Multisystem inflammatory syndrome in children associated with COVID-19 in 101 cases from Turkey (Turk-MISC study).

AIM: Multisystem inflammatory syndrome in children (MIS-C) may cause shock and even death in children. The aim of this study is to describe the clinical features, laboratory characteristics and outcome of children diagnosed with MIS-C in 25 different hospitals in Turkey. METHODS: The retrospective study was conducted between 8 April and 28 October 2020 in 25 different hospitals from 17 cities. Data were collected from patients' medical records using a standardised form. Clinical and laboratory characteristics and outcomes according to different age groups, gender and body mass index percentiles were compared using multivariate logistic regression analysis. RESULTS: The study comprised 101 patients, median age 7 years (interquartile range (IQR) 4.6-9.3); 51 (50.5%) were boys. Reverse-transcriptase polymerase chain reaction (PCR) assay was positive in 21/100 (21%) patients; 62/83 (74.6%) patients had positive serology for SARS-CoV-2. The predominant complaints were fever (100%), fatigue (n = 90, 89.1%), and gastrointestinal symptoms (n = 81, 80.2%). Serum C-reactive protein (in 101 patients, median 165 mg/L; range 112-228), erythrocyte sedimentation rate (73/84, median 53 mm/s; IQR 30-84) and procalcitonin levels (86/89, median 5 µg/L; IQR 0.58-20.2) were elevated. Thirty-eight patients (37.6%) required admission to intensive care. Kawasaki disease (KD) was diagnosed in 70 (69.3%) patients, 40 of whom had classical KD. Most patients were treated with intravenous immunoglobulin (n = 92, 91%) and glucocorticoids (n = 59, 58.4%). Seven patients (6.9%) died. CONCLUSION: The clinical spectrum of MIS-C is broad, but clinicians should consider MIS-C in the differential diagnosis when persistent fever, fatigue and gastrointestinal symptoms are prominent. Most patients diagnosed with MIS-C were previously healthy. Immunomodulatory treatment and supportive intensive care are important in the management of cases with MIS-C. Glucocorticoids and intravenous immunoglobulins are the most common immunomodulatory treatment options for MIS-C. Prompt diagnosis and prompt treatment are essential for optimal management.

COVID-19 associated multisystemic inflammatory syndrome in 614 children with and without overlap with Kawasaki disease-Turk MIS-C study group.

Multisystemic inflammatory syndrome (MIS-C) diagnosis remains difficult because the clinical features overlap with Kawasaki disease (KD). The study aims to highlight the clinical and laboratory features and outcomes of patients with MISC whose clinical manifestations overlap with or without KD. This study is a retrospective analysis of a case series designed for patients aged 1 month to 18 years in 28 hospitals between November 1, 2020, and June 9, 2021. Patient demographics, complaints, laboratory results, echocardiographic results, system involvement, and outcomes were recorded. A total of 614 patients were enrolled; the median age was 7.4 years (interquartile range (IQR) 3.9-12 years). A total of 277 (45.1%) patients with MIS-C had manifestations that overlapped with KD, including 92 (33.3%) patients with complete KD and 185 (66.7%) with incomplete KD. Lymphocyte and platelet counts were significantly lower in patients with MISC, overlapped with KD (lymphocyte count 1080 vs. 1280 cells × µL, p = 0.028; platelet count 166 vs. 216 cells × 103/µL, p < 0.001). The median serum procalcitonin levels were statistically higher in patients overlapped with KD (3.18 vs. 1.68 µg/L, p = 0.001). Coronary artery dilatation was statistically significant in patients with overlap with KD (13.4% vs. 6.8%, p = 0.007), while myocarditis was significantly more common in patients without overlap with KD features (2.6% vs 7.4%, p = 0.009). The association between clinical and laboratory findings and overlap with KD was investigated. Age > 12 years reduced the risk of overlap with KD by 66% (p < 0.001, 95% CI 0.217-0.550), lethargy increased the risk of overlap with KD by 2.6-fold (p = 0.011, 95% CI 1.244-5.439), and each unit more albumin (g/dl) reduced the risk of overlap with KD by 60% (p < 0.001, 95% CI 0.298-0.559). CONCLUSION: Almost half of the patients with MISC had clinical features that overlapped with KD; in particular, incomplete KD was present. The median age was lower in patients with KD-like features. Lymphocyte and platelet counts were lower, and ferritin and procalcitonin levels were significantly higher in patients with overlap with KD. WHAT IS KNOWN: • In some cases of MIS-C, the clinical symptoms overlap with Kawasaki disease. • Compared to Kawasaki disease, lymphopenia was an independent predictor of MIS-C. WHAT IS NEW: • Half of the patients had clinical features that overlapped with Kawasaki disease. • In patients whose clinical features overlapped with KD, procalcitonin levels were almost 15 times higher than normal. • Lethargy increased the risk of overlap with KD by 2.6-fold in MIS-C patients. • Transient bradycardia was noted in approximately 10% of our patients after initiation of treatment.

Serum zinc levels in pediatric patients with COVID-19.

Zinc has potent immunoregulatory and antiviral effects that are critical for growth, immunity, and neurologic development. The aim of this study was to determine the clinical significance of serum zinc levels in pediatric patients with COVID-19 and to demonstrate its association with disease severity. This prospective observational study was conducted between August 3 and November 15, 2020, in pediatric patients aged 1 month to 18 years with confirmed COVID-19 using reverse transcription-polymerase chain reaction. We defined a control group whose serum zinc levels were determined 1 year ago at the same time as those of patients with COVID-19. We used 70 µg/dL as the cut-off zinc value to define zinc deficiency. Statistical analyses were performed using the SPSS for Windows statistics package program. One hundred children with confirmed COVID-19 and 269 children in the control group participated in the study. The median age was 13.3 (IQR: 8-15.4) years in patients with confirmed COVID-19, 11 patients had low serum zinc levels, and 89 patients had normal serum zinc levels. Patients in the group with low zinc levels had a significantly higher hospitalization rate than the group with normal zinc levels (5 (45.5%) and 10 patients (11.2%), respectively) (p = 0.011). The median serum zinc level in patients with COVID-19 was 88.5 mcg/dL (IQR 77.2-100), which was significantly lower than the median level in the control group, which was 98 mcg/dL (IQR 84-111) (p = 0.001). There was no association between the severity of COVID-19 and the serum zinc levels of the children. CONCLUSION: Serum zinc levels may be influenced by many factors such as fasting status, diurnal variation, exercise, and sex, and may give an impression of the zinc status of the population rather than reflecting the individual. The fact that the incidence of hospitalization was significantly higher in patients with both COVID-19 and low serum zinc levels suggests that these patients require a detailed assessment of their living environment. WHAT IS KNOWN: • Serum zinc levels have been found to be low in adult patients diagnosed with COVID-19. • There was a correlation between the severity of COVID-19 and serum zinc levels in adults. WHAT IS NEW: • Children with low serum zinc levels were found to have a higher number of hospitalizations. • No association was found between the severity of COVID-19 disease and serum zinc levels in children.