A Report on a Nationwide Surveillance System for Pediatric Acute Hepatitis of Unknown Etiology in Korea

Background@#Several cases of pediatric acute hepatitis of unknown etiology related to adenoviral infections have been reported in Europe since January 2022. The aim of this study was to compare the incidence, severity, possible etiology, and prognosis of the disease with those in the past in Korea. @*Methods@#The surveillance group collected data between May and November 2022 using a surveillance system. Acute hepatitis of unknown etiology was defined in patients aged 500 IU/L, not due to hepatitis A-E or other underlying causes. For comparison, data from 18 university hospitals were retrospectively collected as a control group between January 2021 and April 2022. @*Results@#We enrolled 270 patients (mean age, 5 years). The most common symptom was fever. However, the incidence was similar between 2021 and 2022. Liver function test results, number of patients with acute liver failure (ALF), liver transplantation (LT), death, and adenovirus detection rates did not differ between the two groups. None of the adenoviruspositive patients in either group experienced ALF, LT, or death. In the surveillance group, adenovirus-associated virus-2 was detected in four patients, one of whom underwent LT. Patients with an unknown etiology showed significantly higher bilirubin levels, a lower platelet count, and a higher LT rate than patients with a possible etiology. @*Conclusion@#The incidence of pediatric acute hepatitis of unknown etiology and adenovirus detection rate have not increased in Korea.

An infant with subglottic cysts presenting as abruptly-progressed stridor and respiratory distress 2 months after extubation

Subglottic cysts are rare but can cause significant airway obstruction that potentially threatens infants’ lives. It is critically important to suspect subglottic cysts in infants with upper-airway obstructive symptoms because it can be treated effectively with only marsupialization without tracheostomy or complicated surgery. Here, we report an infant case of subglottic cyst, who showed prominent stridor and respiratory distress that abruptly progressed 2 months after extubation. The patient was born prematurely and had a history of endotracheal intubation in for a total of 16 days. He was stable with minimal stridor without respiratory distress until he was successfully discharged from the neonatal intensive care unit. However, he showed abrupt progress in stridor and respiratory difficulty about 2 weeks after discharge. Laryngoscopic exam revealed multiple subglottic cysts obstructing the trachea, and all of them were successfully removed by marsupialization. No recurrence of subglottic cysts was observed for 12 months thereafter. Subglottic cysts should be primarily suspected in infants with stridor, especially with a history of prematurity and intubation. Increased awareness of this fatal but curable condition is needed for timely and proper management.