Mycophenolate mofetil embryopathy: A newly recognized teratogenic syndrome

Mycophenolate mofetil (MMF) is probably the most common employed immunosuppressant drug in recipients of solid organ transplant and in many autoimmune diseases. In vitro studies, a significant number of single clinical observations and a recent study from a group of different European teratogen information services, have provided very consistent data supporting the existence of a specific MMF embryopathy. The typical malformative pattern of MMF embryopathy includes external ear anomalies ranging from hypoplastic pinna (microtia) to complete absence of pinna (anotia); cleft lip, with or without cleft palate, and ocular anomalies as iris or chorioretinal coloboma and anophthalmia/microphthalmia. Other less frequent features are congenital heart defects, distal limbs anomalies, esophageal atresia, vertebral malformations, diaphragmatic hernia, and kidney and central nervous system anomalies. Neurodevelopmental outcome seems favorable in the small number of patients where information about this issue is available, but neurological deficits have been documented. Physicians in charge of women under MMF therapy should be aware of the potential risk of this drug to cause a specific embryopathy and the need of interrupting the treatment at least six weeks before becoming pregnant.