Clinical characteristics and genetic variation in respiratory syncytial virus isolated from infants hospitalized due to acute bronchiolitis in Korea during winter season 2016–2017

PURPOSE: Circulating patterns of predominant respiratory syncytial virus (RSV) genotypes in the community may be helpful in understanding molecular epidemiology and predicting future outbreaks of the RSV genotype. We investigated the association of genetic variations in RSV with acute severe bronchiolitis in infants. METHODS: We reviewed medical records of infants younger than 1 year of age hospitalized due to acute bronchiolitis between November 2016 and February 2017. Subjects were classified as severe or mild based on the use of mechanical or noninvasive ventilation. The associations between severity of the disease, sex, age at admission, oxygen saturation at admission and laboratory test results were analyzed. RSV sequence analysis was performed in the severe group. RESULTS: Among 114 infants, 80 underwent respiratory viral polymerase chain reaction using nasopharyngeal swab; of these, 53 (66.3%) showed positive for RSV. Of the 53 RSV-positive samples, 9 were categorized as the severe group and 44 were categorized as the mild group. Male sex, young age, longer duration of admission, minimum SaO2 at admission and bronchiolitis severity score were significantly correlated with disease severity in the severe group than in the mild group (all variables, P < 0.001). Phylogenetic and sequence analysis in the severe group revealed 8 RSV-A, ON1 genotype and 1 RSV-B, BA4 genotype. CONCLUSION: Phylogenetic types of RSV in subjects of the severe group were RSV-A, ON1 genotype or RSV-B, BA4 genotype which were prevalent in the Korean community at the same time. Our study showed that disease severity was not significantly associated with RSV genotypic evolution or antigenic drift in Korea during winter season 2016–17.

Characteristics and prognosis of hepatic cytomegalovirus infection in children: 10 years of experience at a university hospital in Korea / 소아과

PURPOSE: Studies on cytomegalovirus (CMV) infections in immunocompetent children are lacking, and minimal information is available in the medical literature on hepatic manifestations and complications of CMV. The aims of this study were to evaluate the clinical characteristics, laboratory data, and prognosis of children with CMV hepatitis, and to investigate its prevalence at a single medical center in Korea over a 10-year period. METHODS: One hundred thirty-two children diagnosed with CMV infection based on specific markers (anti-CMV IgM, CMV polymerase chain reaction in blood and urine, or CMV culture of urine) were included in the study. Clinical and biochemical characteristics, immunological markers, and outcomes of hepatic CMV infection were determined. RESULTS: The median age of patients (n=132) was 8.5 months (range, 14 days–11.3 years). Peak total bilirubin and alanine aminotransferase levels in serum ranged from 0.11–21.97 mg/dL, and 5–1,517 IU/L, respectively. Alanine aminotransferase remained elevated from 2–48 weeks. Jaundice was the most common clinical feature of hepatic CMV infection during infancy. The hematologic findings revealed anemia, leukocytosis, and monocytosis in CMV-infected patients. All participants recovered without administration of ganciclovir. CONCLUSION: In children with CMV hepatitis, fever was the most common symptom at presentation, and jaundice was the most common clinical feature of hepatic CMV infection in infants younger than 3 months of age. Hepatic CMV infection in immunocompetent children is often a self-limited illness that does not require antiviral therapy, as most patients in this study had favorable outcomes.