Maternal tetrahydrobiopterin deficiency: The course of two pregnancies and follow-up of two children in a mother with 6-pyruvoyl-tetrahydropterin synthase deficiency

Summary

No reports are available about the course of pregnancies in women with tetrahydrobiopterin (BH₄) deficiencies or the effects of treatment with BH₄, l-dopa/carbidopa and 5-hydroxytryptophan (5-OHTrp) on fetal development. We present for the first time the case of a mother with late-diagnosed mild form of 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency, the course of her two subsequent pregnancies and clinical evaluation with follow-up of two offspring. In both pregnancies neurotransmitter precursors, as well as BH₄ dosages were increased proportionally to the mother’s weight gain. To prevent maternal phenylketonuria (MPKU) syndrome, special attention was paid to increasing BH₄ dosages. Both pregnancies were complicated by threatened premature labour, by the mother’s nicotinism and additionally, in the first pregnancy, by gestational diabetes mellitus and vaginitis. The first child was born in the 31st week of pregnancy with the symptoms of moderate intrauterine growth retardation (IUGR) and brain malformation in the form of right sided closed-lip schizencephaly with absence of septum pellucidum. Although the girl demonstrates mild left-sided hemiparesis, her psychological development at the age of 8 years is above average. The second child was born in the 37th week of pregnancy without brain anomalies and at the age of 5 years his psychomotor development is appropriate for the age. As the cause of brain malformations resulting in physical impairment in the first child is unknown, more data are essential to verify conclusions about the influence of the mother’s BH₄ deficiency and the safety of her treatment for fetal development.