Neonatal fibrinogen depletion caused by sodium valproate

Foetal safety of old and new antiepileptic drugs

INTRODUCTION

Drugs teratogenicity has been studied for many years, especially teratogenic effects of antiepileptic drugs, because of the important impact that epilepsy has always had for young women, but data from literature are often conflicting.

AREAS COVERED

We have carried out a critical review of all human studies about the antiepileptic drugs teratogenicity. A systematic search was performed in Medline and PubMed up to May 1, 2015. The use of older antiepileptic drugs in pregnancy is associated with an increased risk of fetus malformations; in particular, Valproate can determine neural-tube-like defects; in Phenytoin and Phenobarbital-exposed pregnancies, orofacial clefts, cardiac and genitourinary malformations are the major anomalies described. Spina bifida is the only specific major congenital malformation significantly associated with exposure to Carbamazepine monotherapy Despite the small number of studies on the teratogenic effects of new antiepileptic drugs, the analysis of the literature shows that exposure of the fetus to the new antiepileptic drugs is associated with a lower risk of major congenital malformations compared to the use of older drugs.

EXPERT OPINION

Where possible, Valproate should be avoided in women of childbearing potential. Results about the safety of newer antiepileptic drugs require validation and further investigation.

Valproate-associated coagulopathies are frequent and variable in children

PURPOSE

Valproic acid (VPA) is an antiepileptic drug (AED) commonly used for generalized and focal epilepsies. The clinical relevance of coagulopathies, known as side effects of VPA therapy, especially thrombocytopenia, von Willebrand disease, and a decrease of factor XIII, is still unclear.

METHODS

In our institute, we noticed a high incidence of clinically relevant coagulation problems related to VPA in eight patients within 1 year only and a further seven children with significant coagulopathy were identified in the context of planned surgery.

RESULTS

We provide an overview of these patients and all six VPA-induced coagulopathies.

CONCLUSIONS

At this time, it cannot be recommended to control all hemostatic parameters in every patient. Whenever an increased bleeding tendency is observed, or before surgical procedures, a platelet count, thrombelastography, prothrombin time, activated partial thromboplastin time, TT, fibrinogen, von Willebrand factor, and factor XIII should be examined. With 385 VPA-treated patients per year and 15 cases of coagulation disorders in this period, we estimate the incidence of coagulation disorders related to VPA in children to be nearly 4%.

Neonatal hypoglycaemia and withdrawal symptoms after exposure in utero to valproate

AIMS

To define, in a prospective study, the risk of hypoglycaemia-defined as blood glucose concentration < 1.8 mmol/l-in term infants exposed in utero to valproate and to describe the withdrawal symptoms.

METHODS

Twenty epileptic women were treated with valproate only during pregnancy and two were treated with valproate and carbamazepine. In the first trimester, the daily median dose of valproate was 1.0 g (range 0.3-4.2) and in the third trimester 1.2 g (range 0.3-4.8).

RESULTS

Thirteen of the 22 infants became hypoglycaemic. One infant had eight episodes of hypoglycaemia, one had three episodes, two had two episodes, and nine had one episode each. The lowest blood glucose concentration was 1.0 mmol/l. All episodes were asymptomatic. The maternal mean plasma concentration of total valproate during the third trimester correlated negatively with blood glucose concentration one hour after delivery (p < 0.0003) and with the development of hypoglycaemia (p < 0.0001). There was no evidence for hyperinsulinaemia as the cause of hypoglycaemia. Ten infants developed withdrawal symptoms, which correlated positively with the mean dose of valproate in the third trimester and the concentration of the free fraction of valproate in maternal plasma at delivery (p < 0.02).

CONCLUSIONS

Infants exposed to valproate in utero had a significantly elevated risk of hypoglycaemia, and withdrawal symptoms were often observed.