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.

Unmasking of neonatal renovascular hypertension by milrinone used for cardiac dysfunction.

A neonate initially presented with heart failure, with severe cardiac dysfunction confirmed by echocardiography, at 3 days of age. Blood pressure at presentation was in the high normal range. It was not until there was a rapid improvement of left-ventricular function on intravenous milrinone that the infant was noted to be hypertensive on day of life 7. It is noteworthy that milrinone, a drug with vasodilator and inotropic properties, paradoxically unmasked hypertension by rapidly improving left-ventricular function. Subsequent work-up showed the etiology of hypertension to be left renal artery stenosis. We present this case to alert clinicians to the rarer causes of left-ventricular dysfunction and to point out that its etiology, i.e., hypertension, may not be apparent until there is improvement in the systolic function of the left ventricle.

An unusual case of severe therapy-resistant hypertension in a newborn.

Hypertension can occur in up to 2% of neonates, and the spectrum of potential causes is broad. Prompt and thorough evaluation with a main focus on kidney disease is key for appropriate therapy. Here we describe a 2-day-old neonate with feeding intolerance and elevated blood pressure readings. Within 24 hours after birth, the infant's blood pressure increased significantly, with sustained mean arterial pressure >85. Renal Doppler ultrasound showed decreased venous blood flow in the right kidney with an abnormal Doppler wave form suggestive of unilateral renal venous thrombosis. Despite aggressive antihypertensive therapy including hydralazine and enalaprilat, hypertension remained sustained. On day-of-life 4, the infant developed clinical signs of hypertensive encephalopathy and significant cardiac dysfunction. A renal angiography showed complete, likely thrombotic occlusion of the right renal artery. Renal MAG3 imaging showed minimal function of the affected kidney, and a nephrectomy secondary to medically uncontrollable hypertension and worsening cardiac dysfunction was performed. The child is developing normally in all aspects on follow-up evaluations at 6 months and 1 year of age. Reevaluation of the working diagnosis in neonates with hypertension can be necessary to optimize the outcome. The overall prognosis can be excellent even in newborns with profound cardiac and neurologic involvement.

Severe hypertension and massive proteinuria in a newborn with renal artery stenosis.

Renal vein thrombosis and the congenital nephrotic syndrome have been associated with nephrotic-range proteinuria/nephrotic syndrome and hypertension in the newborn period. We describe a newborn with severe hypertension and proteinuria secondary to unilateral renal artery stenosis. Proteinuria completely disappeared with blood pressure control (with sodium nitroprusside and an angiotensin-converting enzyme inhibitor). Although renin was not measured, we speculate that proteinuria might have been induced by a high renin state, and was controlled by the angiotensin-converting enzyme inhibitor.

Persistent severe hypertension in an infant with posterior urethral valves.

Severe hypertension, an infrequent problem in pediatrics, usually has a single secondary cause. We report an infant with severe hypertension and left reflux nephropathy, a known cause of secondary hypertension. The severity of hypertension and poor response to pharmacological therapy prompted further investigation, including a renal arteriogram that showed a right segmental renal artery stenosis.

[Symptomatology and treatment of neonatal hypertension]. / Symptomatologie en behandeling van neonatale hypertensie.

A newborn child of a diabetic mother is described, who developed neonatal hypertension after birth. Clinical signs were not specific and the diagnosis would have been missed if blood pressure had not been measured. The cause of the neonatal hypertension appeared to be a thrombus in the left renal artery, probably originating from the ductus arteriosus Botalli. Control of the neonatal hypertension according to a stepwise treatment regime was very difficult. Based on our experience and on study of the literature it is advised to start treatment in the acute stage with nifedipine orally or with sodium nitroprusside intravenously.

Unilateral renal agenesia in the angiographic material and renovascular hypertension.

Analysis of 1216 abdominal aortographies and selective renovasographies undertaken at the Institute of Radiology, Clinical Hospital Centre Rijeka during the period 1979-1985, was performed 39 (3.2%) unilateral renal agenesias were established, a percentage that is significantly higher than reported by other authors. Analysis of all angiographic parameters of a single kidney was also worked out. A significantly high percentage (66.7%) of hypertension was diagnosed in this group. Congenital renal failures make their appearance in the early embryological development and are discovered, if compatible with life, most frequently at an advanced age. Statistical data on the frequency during a lifetime are less reliable because a great number of anomalies are never discovered during a person's life. The etiology of variations and congenital failure of renal arteries is unknown in 90% of the cases, and most of the malformations are without characteristic symptomatology. Since the anatomic relations in anomalous kidney are disturbed, the sign of the disease can develop atypical forms causing frequent errors in diagnosis. The kidney is supplied by numerous lateral branches of the medial sacral artery, i.e. the aorta, during embryological development. Later, some of them degenerate or mutually connect themselves, and the definitive kidney has been usually penetrated by only one artery and one vein on the same side.(ABSTRACT TRUNCATED AT 250 WORDS)

Neonatal renovascular hypertension: haematoma within the renal arterial wall. A case report.

A two-hour-old girl with renovascular hypertension is presented. After aggressive antihypertensive medication, nephrectomy was carried out, but she expired soon after operation. Autopsy revealed intramural haematomas between the media and the adventitia at the centre of both renal arteries where the luminal occlusions were observed.