Introduction: COVID-19-related anosmia is a remarkable and disease-specific finding. With this multicenter cohort study, we aimed to determine the prevalence of anosmia in pediatric cases with COVID-19 from Turkey and make an objective assessment with a smell awareness questionnaire. Material and Methods: This multicenter prospective cohort study was conducted with pediatric infection clinics in 37 centers in 19 different cities of Turkey between October 2020 and March 2021. The symptoms of 10.157 COVID-19 cases 10–18 years old were examined. Age, gender, other accompanying symptoms, and clinical severity of the disease of cases with anosmia and ageusia included in the study were recorded. The cases were interviewed for the smell awareness questionnaire at admission and one month after the illness. Results: Anosmia was present in 12.5% (1.266/10.157) of COVID-19 cases 10-18 years of age. The complete records of 1053 patients followed during the study period were analyzed. The most common symptoms accompanying symptoms with anosmia were ageusia in 885 (84%) cases, fatigue in 534 cases (50.7%), and cough in 466 cases (44.3%). Anosmia was recorded as the only symptom in 84 (8%) of the cases. One month later, it was determined that anosmia persisted in 88 (8.4%) cases. In the smell awareness questionnaire, the score at admission was higher than the score one month later (P < 0.001). Discussion: With this study, we have provided the examination of a large case series across Turkey. Anosmia and ageusia are specific symptoms seen in cases of COVID-19. With the detection of these symptoms, it should be aimed to isolate COVID-19 cases in the early period and reduce the spread of the infection. Such studies are important because the course of COVID-19 in children differs from adults and there is limited data on the prevalence of anosmia.

Febrile neutropenia (FN) is an important complication that causes high rates of morbidity and mortality in patients with malignancies. We aimed to investigate the etiology, epidemiological distribution and its change over the years, clinical courses, and outcomes of FN in children with acute leukemia. We retrospectively analyzed the demographic data, clinical characteristics, laboratory results, severe complications, and mortality rates of pediatric patients with FN between January 2010 and December 2020. In 153 patients, a total of 450 FN episodes (FNEs) occurred. Eighty-four (54.9%) of these patients were male, the median age of the patients was 6.5 (range: 3-12.2) years, and 127 patients (83%) were diagnosed with acute lymphoblastic leukemia. Fever with a focus was found in approximately half of the patients, and an etiology was identified for 38.7% of the patients. The most common fever focus was bloodstream infection (n=74, 16.5%). Etiologically, a bacterial infection was identified in 22.7% (n=102), a viral infection in 13.3% (n=60), and a fungal infection in 5.8% (n=26) of the episodes. Twenty-six (23.2%) of a total of 112 bacteria were multidrug resistant (MDR) The rate of severe complications was 7.8% (n=35) and the mortality rate was 2% (n=9). In logistic regression analysis, refractory/relapsed malignancies and high C-reactive protein (CRP) at first admission were found to be the most important independent risk factors for mortality. Prolonged neutropenia after chemotherapy, diagnosis of acute myeloid leukemia, identification of fever focus or etiological agents, invasive fungal infections, polymicrobial infections, and need for intravenous immunoglobulin treatment increased the frequency of severe complications. We found that there was no significant change in the epidemiological distribution or frequency of resistant bacteria in our center in the last 10 years compared to previous years. Prolonged duration of fever, relapsed/refractory malignancies, presence of fever focus, and high CRP level were significant risk factors for poor clinical course and outcome.

Background/aim: It is still not known how an immunosuppressive state affects the response to coronavirus disease 2019 (COVID-19) in children and adolescents. The aim of this study was to evaluate clinical characteristics, outcomes, and follow-up results of COVID-19 in pediatric patients with a history of immunocompromise or malignancy, retrospectively. Materials and methods: Patients with a diagnosis of COVID-19 who were under 18 years of age and had a history of immunosuppressive chronic disease or under immunosuppressant treatment were included in the study. Patients were applied to our outpatient clinic or consulted to our department in a tertiary center during the first year of the pandemic. Results: We evaluated 18 patients with a median age of 15.0 (0.6-17.8) years. Twelve patients (66.6%) were tested because of a symptom and the most common symptom was fever (44.4%, n = 8). Ten of the symptomatic patients (55.5% of all cohort) had a mild disease, the remaining two patients (11.1%) with an end-stage malignancy had critical diseases. Twelve patients (66.7%) were managed on an outpatient basis and were followed up at home, while the remaining six (33.3%) required hospitalization. One patient, who had Ewing sarcoma, died during the follow-up in the intensive care unit, and others were recovered without any morbidities. Lymphocyte (LYM) counts were significantly lower, C-reactive protein (CRP), and ferritin levels were higher in the individuals that needed hospitalization (p = 0.039, 0.027, and 0.039, respectively). Conclusion: Immunocompromised children and adolescents with COVID-19 should be monitored closely, especially those with an end-stage malignancy, low LYM count, or high CRP and ferritin levels.

The pathophysiology of multisystem inflammatory syndrome in children (MIS-C) and associated oral symptoms have not been clarified yet. The aim of the present study was to compare the oral health status of children with MIS-C-associated Coronavirus disease 2019 (COVID-19) and COVID-19. A total of 54 children with SARS-CoV-2 infection, 23 with MIS-C-associated COVID-19 and 31 with asymptomatic, mild, and moderate COVID-19 were recruited for the present cross-sectional study. Sociodemographic variables, medical examinations, oral hygiene habits, and extraoral and intraoral findings (DMFT/dmft index, OHI scores, and oral mucosal changes) were recorded. The t-test for independent samples and the Mann-Whitney U test were used (p < 0.05). MIS-C was found to be associated with chapped lips (all patients) and oral mucosal changes, including erythema, white lesion, strawberry tongue, and swelling of the gingiva as compared to the COVID-19 group (frequency of more than one mucosal change: 100% vs. 35%) (p < 0.001). Children with MIS-C presented higher DMFT/dmft scores (DMFT/dmft 5.52 ± 3.16 for the MIS-C group vs. 2.26 ± 1.80 for the COVID-19 group) (p < 0.01). Elevated OHI scores were also associated with MIS-C (mean ± SD: 3.06 ± 1.02 (MIS-C) vs. 2.41 ± 0.97 (COVID-19) (p < 0.05). Oral manifestations, mainly strawberry and erythematous tongue, were characteristic features of MIS-C. Prevalence of oral/dental symptoms was elevated in children with MIS-C when compared to COVID-19. Therefore, dental professionals should be aware of the oral manifestations associated with MIS-C, which may have high mortality and morbidity rates.