A Case of Congenital Myasthenia Gravis due to ChAT Gene Mutation in a Term Neonate: A Case Report.

Congenital myasthenia gravis syndrome (CMS) is a rare genetic heterogeneous disorder due to abnormal neuromuscular transmission caused by several genes. CMS caused by choline acetyltransferase (ChAT) gene mutations have been reported in 53 cases since 2020, and only three of them have been identified as hemizygous mutations. A 1-day-old term neonate was transferred from the nursery to the neonatal intensive care unit on 10 L of oxygen by face mask due to respiratory distress.

Langerhans cell histiocytosis presenting as a blueberry muffin rash.

Langerhans cells, often referred to as the "macrophages of the skin", are dendritic cells that normally reside in the epidermis and papillary dermis. Just like macrophages, they function as antigenpresenting cells that activate naive T cells. Certain mutations such as those involving the gene can cause unopposed production of Langerhans cells, which is known as Langerhans cell histiocytosis (LCH).