Endocrine Abstracts

Precedents: Thirty-nine year old Woman. Classic phenylketonuria diagnosed for neonatal screening in Germany. Good adherence to the diet from the infancy, with good metabolic control. Not response to test with BH4.

Pregnancy in 2007 with good controls of phenylalanine (Phe). Son with congenital cardiopathy.

Evolution: In 2013 she planed new pregnancy, departing from very good controls (<4 mg/dl) and ingestion of 22–24 Phe’s rations and supplements without Phe.

She did Phe and tyrosine controls weekly (Tyr), analysis with plasmatic amino acids and dietary survey quarterly.

In 24 pregnancy week O’Sullivan test was pathological (164 mg/dl). Oral overload of glucose was not tolerated. She had fast glycemias between 99 and 121 mg/dl and postprandial glycemias up to 146–169 mg/dl.

Initially controlling the ingestion of carbohydrates improved the glycemic control. In the third quarter the low levels of Phe and Tyr did necessarily to increase up to duplicating Phe’s rations. Since the patient could not take proteins of high biological value, she increased the ingestion of vegetables, potatoes and changed the cereals, pasta and rice without proteins into others of normal content into proteins. This implied a deterioration of the glycemic control that derived in the prescription of Insulin NPH in two doses, and rapid insulin for postprandial control with good later control. She needed supplementation with tyrosine.

The childbirth was without incidents, with a healthy newborn child. Later she returned to reduce Phe’s rations of the diet, tyrosine supplement and insulin therapy was suspended.

Discussion: The syndrome of maternal phenylketonuria appears in children of mothers affected for seriously or moderated hiperphenylalaninemia with Phe’s plasmatic high concentrations during the previous months and/or the gestation. It involves in the fetus mental delay, microcephaly, cardiac malformations, atresia of esophagus and dismorfias facial, between others. The Phe crosses the placenta and high concentrations of the same one are difficultly metabolizables due to the foetal immaturity. It is indispensable to contribute quantity of proteins and energy adapted and to evaluate the contribution of proteins of formula without Phe. We report a case in the one that is necessary to be increasing Phe’s rations based on food and supplements rich in carbohydrates, which complicates the managing of the pregnancy diabetes and it us forces the insulinoterpy, since it is not possible to reduce the ingestion of carbohydrates because a minor caloric contribution in patients with phenylketonuria would worsen Phe’s levels.