The Nutmeg Lung Pattern in a Fetus with Hypoplastic Left Heart Syndrome and Turner Syndrome

The "nutmeg lung pattern" on fetal magnetic resonance imaging (MRI) indicates pulmonary lymphangiectasia. This is associated with adverse outcomes, particularly in fetuses with congenital heart defects and impaired pulmonary venous return. Whereas lymphedema is common in fetuses with Turner syndrome, pulmonary lymphangiectasia is not. A 26-year-old woman presented with a fetus with hypoplastic left heart syndrome (HLHS) without restrictive atrial septum (RAS). The family declined amniocentesis, yet non-invasive prenatal testing showed an increased risk for Turner syndrome. The patient underwent a fetal MRI as part of a blinded research protocol. Postnatal echocardiogram confirmed the fetal echocardiographic findings without evidence of RAS. Norwood stage I palliation was performed at two days of age. Significant neonatal respiratory morbidity including pneumonia, diaphragmatic and vocal cord pareses and chylothorax occurred. Subsequent review of fetal MRI revealed a prominent thoracic duct and mild pulmonary lymphangiectasia. Turner syndrome was confirmed by genetic testing. After one month, the patient was discharged to her home hospital with respiratory support, which was discontinued a few weeks later. Respiratory problems continued, but the vocal cord paresis resolved over time. This is a unique case of a fetus with HLHS/non-RAS with mild fetal pulmonary lymphangiectasia, and significant neonatal respiratory morbidity, probably in part due to Turner syndrome. The infant survived the neonatal period and underwent uneventful Glenn surgery. The patient's tolerance to the total cavopulmonary connection (TCPC) procedure is yet to be seen. An MRI lymphography should precede it to assess residual lymphatic abnormalities and serve as baseline for post-TCPC changes.