Background: Neonatal morbidities are major determinants of clinical outcomes and healthcare utilization in preterm infants. However, population-level evidence quantifying the cumulative contribution of neonatal morbidities to neonatal intensive care unit (NICU) length of stay (LOS) and medical costs remains limited. Methods: We conducted a nationwide retrospective cohort study using the Korean Health Insurance Review and Assessment Service database. Preterm infants admitted to NICUs between 2020 and 2023 were identified. After exclusions, 30,034 infants with complete birth weight data and 31,240 with complete gestational age data were included. Major neonatal morbidities—including bronchopulmonary dysplasia (BPD), patent ductus arteriosus (PDA), sepsis, intraventricular hemorrhage (IVH), retinopathy of prematurity (ROP), necrotizing enterocolitis (NEC), and periventricular leukomalacia (PVL)—were identified using ICD-10 odes. Associations of individual morbidities and cumulative morbidity burden with NICU LOS and medical costs were evaluated using multivariable regression and generalized linear mixed models. Results: Mean NICU LOS was 26.5 days, and mean total medical cost was 41.9 million KRW. All major morbidities were associated with prolonged LOS and increased costs. BPD showed the strongest association with LOS, whereas NEC and sepsis were associated with the highest costs. NICU LOS and medical costs increased in a stepwise manner with increasing numbers of morbidities; each additional morbidity was associated with an 8.0-day increase in LOS and a 32.5 million KRW increase in medical costs (both p < 0.001). Conclusions: Greater cumulative morbidity burden was associated with prolonged hospitalization and increased healthcare costs in preterm infants.
Megalencephaly-capillary malformation-polymicrogyria syndrome (MCAP) is a rare genetic disorder characterized by megalencephaly, polymicrogyria, body overgrowth, and cutaneous capillary malformations. It has been reported recently that MCAP is related to a somatic mosaic mutation in the phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) gene. We report a case of hemimegalencephaly with polymicrogyria and cutaneous capillary malformations diagnosed by genetic evaluation of MCAP in the neonatal period. The PIK3CA mutation [c.1635G>T (p. Glu545Asp)] was determined by Sanger sequencing. The patient was treated with a ventriculoperitoneal shunt for progressive hydrocephalus. Because of the dynamic, progressive clinical manifestations and tumor-prone traits of MCAP, early diagnosis is important. Moreover, since the phosphoinositide 3-kinase (PI3K)-specific inhibitor, a targeted therapy for the PI3K/AKT/mTOR signaling pathway is emerging as a new therapy, early genetic diagnosis is becoming increasingly important.