Antenatal Bartter syndrome: a rare cause of unexplained severe polyhydramnios

Abstract

A woman presented with polyhydramnios at 22 weeks of gestation with a structurally normal fetus and placenta. Biochemical analysis of amniotic fluid detected a very high level of chloride (582 mmol/L), which led to the diagnosis of Bartter syndrome. With serial amniocentesis and indomethacin therapy, the pregnancy continued to 36 weeks. Neonatal and subsequent investigations further supported the diagnosis of Bartter syndrome. The infant was well at birth and now, at 5 months of age, is gaining weight normally on indomethacin.

Antenatal Bartter Syndrome: A Review

“…The normal blood pressure despite high levels of renin and angiotensin is thought to be due to nonresponsive of their blood vessels to angiotensins [1–7]. Continuous loss of calcium in urine results in nephrocalcinosis [2–4]. …”

“…Mothers of fetus with Bartter syndrome often present with unexplained polyhydramnios between 24 and 30 weeks of gestation [3, 4, 7]. Intrauterine growth restriction may also be associated.…”

“…Inability of the kidney tubule to retain salt and water results in fetal polyuria. Important biochemical abnormality in amniotic fluid is normal sodium and potassium but consistently elevated chloride levels [4, 8–12]. Infants are usually born preterm.…”

“…The awareness of the condition is important for early recognition. The typical features include fetal polyuria, early onset maternal polyhydramnios, intrauterine growth restriction, preterm birth, postnatal polyuria, episodes of dehydration, recurrent vomiting, and failure to thrive [3, 4]. Another syndrome, Gitelman syndrome, is often called as variant of Bartter syndrome.…”

Síndrome de Bartter como causa de polihidramnios severo. A propósito de un caso

“…Suele ocurrir en pacientes con diabetes gestacionales mal controladas, anomalías fetales (generalmente del tracto gastrointestinal), alteraciones cromosómicas y defectos del tubo neural, tales como anencefalia. Los polihidramnios sin causa identificada constituyen un reto para los obstetras, y el síndrome de Bartter debería ser sospechado en los polihidramnios severos y precoces sin anomalías fetales aparentes 10 . Pese a ser una enfermedad muy poco frecuente (1,2/100.000 RN) debería plantearse realizar la cuantificación de cloro en el líquido amniótico ante un polihidramnios severo e idiomático para poder realizar un adecuado diagnóstico prenatal.…”