RESUMO
The phosphocreatine/creatine system is fundamental for the proper development of the embryonic brain. Being born prematurely might alter the creatine biosynthesis pathway, in turn affecting creatine supply to the developing brain. We enrolled 53 preterm and very preterm infants and 55 full-term newborns. The levels of urinary guanidinoacetate, creatine, creatinine and amino acids were measured in the preterm and very preterm groups, 48 h and 9 days after birth and at discharge, and 48 h after birth in the full-term group. Guanidinoacetate concentrations of both preterm and very preterm newborns were significantly higher at discharge than the values for the full-term group at 48 h, while very preterm infants showed urinary creatine values significantly lower than those measured in the full-term group. Our results suggest an impairment of the creatine biosynthesis pathway in preterm and very preterm newborns, which could lead to creatine depletion affecting the neurological outcome in prematurely born infants.
Assuntos
Arginina/metabolismo , Creatina/metabolismo , Glicina/análogos & derivados , Recém-Nascido Prematuro/metabolismo , Redes e Vias Metabólicas , Arginina/urina , Peso ao Nascer/fisiologia , Estudos de Casos e Controles , Creatina/biossíntese , Creatina/sangue , Creatina/urina , Feminino , Idade Gestacional , Glicina/metabolismo , Glicina/urina , Humanos , Lactente Extremamente Prematuro/sangue , Lactente Extremamente Prematuro/metabolismo , Lactente Extremamente Prematuro/urina , Recém-Nascido/sangue , Recém-Nascido/metabolismo , Recém-Nascido/urina , Recém-Nascido Prematuro/sangue , Recém-Nascido Prematuro/urina , Masculino , Redes e Vias Metabólicas/fisiologia , Modelos BiológicosRESUMO
OBJECTIVE: To report a case of nonidentical twins affected with a congenital form of Steinert's myotonic dystrophy (DM1), conceived by IVF owing to parental sterility, in which the mother presented a paucisymptomatic form of DM1 which was diagnosed as a result of the condition inherited by the twins. DESIGN: Case report. SETTING: Neonatal intensive care unit of a tertiary hospital. PATIENT(S): Newborn twins affected with the congenital form of DM1 and a 35-year-old nulliparous mother. INTERVENTION(S): In vitro fertilization. MAIN OUTCOME MEASURE(S): Molecular study of the CTG triplet expansion related with DM1. RESULT(S): Molecular study evidenced a pathologic expansion in both twins as well as in their mother. CONCLUSION(S): This case should serve as a reminder to practitioners that assisted reproductive techniques have opened the possibility that asymptomatic or paucisymptomatic carriers of a genetic syndrome can inadvertently conceive fetuses affected with more serious forms of the illness.
