Atypical Neonatal Marfan Syndrome with p.Glu1073Lys Mutation of FBN1: the First Case in Korea

Neonatal Marfan syndrome (nMFS) is considered to be on the most severe end of the spectrum of type I fibrillinopathies. The common features of nMFS include ascending aortic dilatation, severe mitral and/or tricuspid valve insufficiency, ectopia lentis, arachnodactyly, joint contractures, crumpled ear, loose skin, and pulmonary emphysema.We describe a newborn male diagnosed with nMFS. He presented several atypical features, such as diaphragmatic eventration, severe hydronephrosis with hydroureter, and dilated cisterna magna. Molecular analysis revealed a missense mutation at nucleotide 3217 (c.3217G>A) in exon 26 of the fibrillin-1 (FBN1) gene, resulting in the substitution of a glutamate for a lysine at codon 1073 (E1073K) in the 12th calcium binding epidermal growth factor-like domain of the FBN1 protein. Here we report a rare case of Nmfs with several combined atypical features, such as diaphragmatic eventration, severe hydronephrosis with hydroureter, and dilated cisterna magna. Our report is the first atypical nMFS case with p.Glu1073Lys mutation of FBN1 in Korea and may help clinicians with the diagnosis and follow-up of atypical nMFS.