Fetal congenital midaortic syndrome with unilateral renal artery stenosis prenatally presenting with polyhydramnios and postpartum as hyponatremic hypertensive syndrome.

The midaortic syndrome (MAS) is a rare anomaly, characterised by narrowing of the distal aorta and its major branches. The most common symptom is severe arterial hypertension. The combination of hyponatremia, polyuria and renovascular hypertension caused by a unilateral renal artery stenosis is described as hyponatremic hypertensive syndrome. We report a case of MAS with unilateral renal artery stenosis in a preterm female neonate. A pregnant woman at 34 weeks of gestation was referred with fast growing abdominal circumference and pain. The ultrasound revealed severe polyhydramnios and fetal myocardial hypertrophy. Within the first 48 hours of the neonatal period, the diagnosis of MAS was made. We conclude that symptomatic MAS, caused by unilateral renal artery stenosis, resulting in increased renin-angiotensin-aldosterone system activity and subsequent polyuria of the non-stenotic kidney, lead to clinically significant polyhydramnios.

Severe hyponatraemia associated with pre-eclampsia.

Pre-eclampsia is a multisystem disorder with incidence rates ranging from 2% to 5%. Hyponatraemia is a rare complication of pre-eclampsia. A 41-year-old, para 0+1 in vitro fertilisation monochorionic diamniotic triplet pregnancy woman presented at 25 weeks with dyspnoea and general malaise. Her antenatal course was complicated by the diagnosis of intrauterine growth restriction in triplet one at 27 weeks of gestation. At 27+3 weeks gestation, she was diagnosed as having pre-eclampsia. Subsequent biochemical analysis demonstrated hyponatraemia with serum sodium falling steadily to 117 mmol/L over the next 19 days. She was admitted to intensive care unit for stabilisation of fulminant pre-eclampsia and severe hyponatraemia at 30+5 weeks of gestation. Hypertonic saline and intravenous labetolol were administered prior to delivery by caesarean section. She recovered well postdelivery with stabilisation of her blood pressure and normalisation of her sodium level to 135 mmol/L. Awareness and frequent monitoring of hyponatraemia should become an integral part of monitoring women with pre-eclampsia.

Neonatal hyponatremia: differential diagnosis and treatment.

Hyponatremia is very frequent in neonates, especially in VLBW. Recent data have shown that hyponatremia is not so benign as previously believed,and several clinical studies have indicated that preterms with mild to moderate chronic hyponatremia may experience poor growth and development retardation. The aim of this review is to present how to differentiate hypovolemic, euvolemic and hypervolemic hypernatremias, suggesting algorithms for practical management.

[Oxytocin and syndrome of inappropriate secretion of antidiuretic neonatal hormone. Case report of early severe hyponatremia and literature review]. / Oxitocina y sindrome de secreción inapropiada de hormona antidiurética neonatal. Reporte de un caso de hiponatremia severa temprana y revisión de la bibliografia.

This is a clinical case presentation of a full term newborn infant who suffered severe hyponatremia and early seizures, associated with maternal fluid overload with electrolyte free solutions and high doses of oxytocin for labor augmentation. Although this condition has been recognized since the 1960's with isolated reports, this particular case has features that needs further investigation, not only for the unsually severe hyponatremia, but most importantly we think, for the prominent signs of fluid retention, the infant had, that suggest excessive antidiuretic activity probably due to oxytocin. These findings are consistent with syndrome of inappropriate secretion of antidiuretic hormone. Although until now there is no proof that oxytocin by itself produces this syndrome. We think the association is possible in certain clinical circumstances, such as those found in this case. We also, briefly discussed the pathophysiology of perinatal hyponatremia, the neonatal treatment of this condition and the current guidelines for the women in labor. Hyponatremia should not be considered a benign condition, since in the neonate, it may affect brain function.

Adrenal insufficiency and abnormal genitalia in a 46XX female with Smith-Lemli-Opitz syndrome.

OBJECTIVE: To report the first case of a 46XX female infant with Smith-Lemli-Opitz syndrome (SLOS), adrenal insufficiency and abnormal genitalia. METHODS: The patient was assessed for hormonal status on day 4 and 6 months later and was followed-up from the study time (2.5 years of age). RESULTS: The patient had a persistent urogenital sinus, posterior labial fusion without clitoromegaly. She presented with a salt-wasting syndrome on day 4. Adrenal insufficiency was confirmed. Adrenal androgen levels, including 17-hydroxyprogesterone and 11-deoxycortisol were moderately elevated. CONCLUSION: Children with SLOS should be assessed for adrenal insufficiency. In female infants, abnormal external genitalia can be observed even if the precise mechanism behind these abnormalities is yet to be determined.

The hyponatremia of neonatal urinary ascites: clinical observations, experimental confirmation and proposed mechanism.

A case of neonatal urinary ascites with severe hyponatremia is reported. Critical review of the literature on neonatal urinary ascites, which included determination of serum electrolytes, revealed a 70% incidence of hyponatremia. In an attempt to explain the mechanism of the hyponatremia, urinary ascites was produced in rats by creation of either a unilateral (uretero-peritoneal) or bilateral (vesicoperitoneal) shunt. Hyponatremia did not occur in the unilateral group but it was profound in the bilateral group. At 48 hours postoperatively renin was unchanged in the unilateral group but it was significantly elevated in the bilateral group. Aldosterone was elevated in the unilateral group and markedly elevated in the bilateral group. Urine entering the peritoneal cavity equilibrates with plasma. The proposed mechanism of hyponatremia in the bilateral group is autodialysis with intraperitoneal urine containing progressively lower sodium concentration secondary to increased renin and aldosterone.