Since December 2019, coronavirus disease 2019 (COVID-19) cases have been reported. The clinical features of COVID-19 in children are different from those in adults including morbidity and mortality. Even in infants and children, the clinical features are different according to ages in some cases. The children are commonly coinfected to diverse respiratory viruses, and therefore physicians, who take care of infants and children infected with COVID-19, have to consider diverse clinical aspects in their patients infected with COVID-19. In this review, we have summarized the clinical features of COVID-19 in children.

Background: The tuberculin skin test (TST) is used in children who have been in contact with tuberculosis (TB). The test has limitations in terms of operator variability and the need for a second visit at 48–72 h for interpretation. Serum adenosine deaminase (ADA) was studied in adults and found to have a strong correlation with TST. Until now no data are available in the pediatric population. Objective: To examine the correlation between serum ADA and the TST in children who had been in contact with TB. Materials and Methods: A prospective study was conducted at Songklanagarind Hospital in southern Thailand among children aged 2–15 years with a history of contact TB between 2016 and 2018. Serum ADA was obtained before performing the TST. Children with active TB disease were excluded from the analysis. Results: Sixty-seven children were enrolled. The serum ADA ranged from 9.3–43 IU/L. The overall correlation between serum ADA and TST was poor (ρ = −0.03, P = 0.84). However, a subgroup analysis excluding 32 children with TST size 0 mm and a high variation of serum ADA (10–37.6 IU/L) found that in the remaining children, serum ADA and TST had a moderate correlation with statistical significance (ρ = 0.48, P = 0.004). Conclusions: The correlation between serum ADA and TST in contact TB pediatric patients was poor. The cause of low correlation was due to a high variability of serum ADA level in children who had no reaction to TST.

Objectives: Although children with complicated parapneumonic effusions (CPEs) clinically improve within weeks after being discharged from the hospital, it remains unclear whether the injury and subsequent repair of the damaged lung allow a full return to premorbid lung function. We investigated the pulmonary function status in children whose CPE had been treated with different modalities. Patients and Methods: We therefore enrolled forty patients with a history of CPE: (1) patients treated with systemic antibiotics and conventional chest tube therapy only (control Group 1, n = 11); (2) patients treated with systemic antibiotics, conventional chest tube therapy, and intrapleural fibrinolytic therapy (Group 2, n = 20); and (3) patients treated with surgical intervention in addition to prior medical treatment (Group 3, the surgical rescue group, n = 9). Pulmonary function tests were done when patients had been discharged at least for 1 year. We used a spirometry test for pediatric pulmonary functions. Results: The basic demographic data of the three groups were not significantly different. The forced volume vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were significantly higher in Group 2 patients (percentage of the predicted value in FVC: 87.6% ± 8.5% versus 79.2% ± 13.4% (Group 1) vs. 77.6% ± 9.0% (Group 3)). Significantly, fewer Group 2 patients had abnormal pulmonary function (P < 0.05). Conclusions: Our data support a growing body of evidence that empyema in children may lead to reduced lung function later in life for a subset of patients.