Clinical Features and Outcomes of Omicron-Associated Croup in Children

Abstract

Objective: This study was aimed to describe the clinical features and outcomes of Omicron-associated croup in children. Methods: A total of 105 children aged 3-60 months (median age 11 months) with coronavirus disease 2019 (COVID-19) and cough were admitted to our hospital from December 16, 2022, to December 31, 2022. Their clinical features, treatment, and outcomes were reviewed. These children were followed up for 8 months. Results: Among the cases, 5 had complex medical histories, while the other children were generally healthy. Out of the cases, 41 (38.3%), 57 (54.4%), and 7 (6.7%) had mild, moderate, and severe laryngeal obstruction, respectively. They developed croup after 1-5 days of fever (median 2 days). The majority (90.5%) of COVID-19 children with croup did not have pneumonia, and most of them (64.8%) had decreased eosinophil counts. Additionally, most other blood routine indicators were normal. Five other viral infections (chlamydia pneumoniae, respiratory syncytial virus, adenovirus, coxsackie virus, and mycoplasma pneumoniae) were tested in 51 cases, and all results were negative. All cases recovered from croup after receiving prompt nebulization therapy and/or intravenous drip of hormone. The hospitalization rate was 6.7%. During the 8-month follow-up period, 71 cases experienced repeated fever due to various infections, but only 4 cases (4/105, 3.8%) had repeated croup. Conclusion: Omicron is a risk factor for croup, with most cases presenting mild to moderate laryngeal obstructions. Co-viral infection testing is unnecessary for such cases. The symptoms of Omicron-associated croup may be more severe than croup associated with other viruses; however, unnecessary hospitalizations can be avoided, leading to reduced healthcare expenses.