Peroxisomal D-bifunctional protein (DBP), encoded by the HSD17B4 gene, catalyzes β-oxidation of very long chain fatty acids (VLCFAs). The deficiency of this peroxisomal enzyme leads to the accumulation of VLCFAs, causing multisystemic manifestations including the brain, retina, adrenal gland, hearing, and skeletal system. Herein, we report the first Korean neonatal case of peroxisomal DBP deficiency and the clinical prognosis over 2 years. This patient showed craniofacial dysmorphism, club foot, and seizures with cyanosis one day after birth. Elevated VLCFAs levels were indicative of a peroxisomal disorder. Targeted exome sequencing was performed and two missense mutations p.Asp117Val and p.Phe279Ser in the HSD17B4 gene were identified. The patient had type III DBP deficiency; therefore, docosahexaenoic acid and non-soluble vitamins were administered. However, progressive nystagmus, optic nerve atrophy, and bilateral hearing defects were observed and follow-up brain imaging revealed leukodystrophy and brain atrophy. Multiple anti-epileptic drugs were required to control the seizures. Over two years, the patient achieved normal growth with home ventilation and tube feeding. Hereby, the subject's parents had support during the second pregnancy from the proven molecular information. Moreover, targeted exome sequencing is an effective diagnostic approach, considering genetic heterogeneity of Zellweger spectrum disorders.

Lymphomatoid granulomatosis (LYG) is an Epstein-Barr virus (EBV)-associated lymphoproliferative disease. It is considered a rare entity in pediatric patients. An adolescent male with lobar consolidation suspected of having pneumonia was resistant to antibiotics and had persistently abnormal radiographs with chest pain. The patient was diagnosed with pulmonary LYG through video-assisted thoracoscopic surgery (VATS) lung biopsy. He received eight cycles of rituximab, vincristine, cyclophosphamide, and prednisolone (R-CVP) but had progressive disease. As the patient developed hypogammaglobulinemia after eight courses of rituximab, he received intravenous gamma globulin (IVIG) at regular interval. With immune augmentation effect of IVIG and immune modulation treatment with prednisolone, the patient has shown no aggravation of the lung lesions. Considering its rarity, high mortality, and frequent relapses, diagnostic methods investigating the radiologic abnormalities can help in early treatment initiation.

A measles outbreak with 20 confirmed cases occurred at a local children’s hospital in Daejeon from March 28 to April 21, 2019. The index patient was a 7-month-old girl with a recent history of travel to Vietnam. Contact tracing, active surveillance, and post-exposure prophylaxis were conducted by health authorities. Among the 20 patients, 11 (55%) were infants (0–11 months of age), three (15%) were aged 1–3 years, one (5%) was aged 4 years, and five (25%) were adults. Fifteen (75%) patients did not have a history of measles vaccination, and five (25%) had received only one vaccine dose. This study described the importance of prompt application of infection control measures in susceptible environments, including hospitals. Age-appropriate vaccination and providing information on infectious diseases to international travelers and multicultural families in Korea is vital.