Mutations in genes critical for surfactant metabolism, including surfactant protein C (SP-C) and ABCA3, are well-recognized causes of interstitial lung disease. Recessive mutations in ABCA3 were first attributed to fatal respiratory failure in full-term neonates, but they are also increasingly being recognized as a cause of respiratory disorders with less severe phenotypes in older children and also adults. Here, we report a 20-month-old boy with interstitial lung disease caused by two distinct ABCA3 mutations. Initial treatment with methylprednisolone was unsuccessful, but the additional administration of hydroxychloroquine was effective. The family history revealed that the patient's older brother had died of idiopathic interstitial lung disease at 6 months of age, suggesting a genetic etiology of the disease. Sequence analyses of SP-C and ABCA3 genes were performed using DNA samples from the patient himself, his parents, and his brother. These analyses revealed novel compound heterozygous mutations in the coding exons of ABCA3 in both the patient and his brother: c.2741A > G, of paternal origin, and c.3715_3716insGGGGGG, of maternal origin. Conclusion Since ABCA3 mutations seem to be a heterogeneous entity with various phenotypes, we recommend genetic testing for mutations in SP-C and ABCA3 genes to be considered in children with unexplained interstitial lung disease.

We herein report the successful treatment of a 4-year-old girl with left ventricular noncompaction (LVNC) who presented with incessant ventricular fibrillation at 5 months of age. An implantable cardioverter defibrillator (ICD) was implanted, and dual chamber (DDD) pacing was initiated at 7 months of age. At her 10-month follow-up, her left ventricular ejection fraction (LVEF) had decreased from 45% to 20% with mechanical dyssynchrony. After upgrading to cardiac resynchronization therapy (CRT), the LVEF improved to 50%. The usefulness of CRT in pediatric LVNC has not been fully elucidated. However, our case suggests that CRT therapy may be an effective option for LVNC-induced cardiac dysfunction.

Propionic acidemia is an autosomal recessive disorder that is due to deficiency in the enzyme propionyl-CoA carboxylase. Cardiomyopathy is a well-known phenomenon in propionic acidemia that it may rapidly progress to death. Here we describe a case of propionic acidemia in a 27-yearold man who developed adult-onset secondary dilated cardiomyopathy. In early infancy he was diagnosed with propionic acidemia and was later noted to have mild mental retardation, mild renal failure, and optic nerve atrophy. Although he was in good energy status with a low-protein diet and carnitine supplementation, he was admitted to our university hospital with decompensate heart failure, which resulted in low-output cardiac syndrome with massive mitral regurgitation and left ventricular dyssynchrony. Cardiac resynchronization therapy (CRT) and continuous hemodiafiltration followed by hemodialysis (HD) dramatically improved his clinical status.