Case report: Neonatal hypertension

Background: Neonatal arterial hypertension is rare with an incidence between 0.2 - 3 %. Clinical presentation varies widely and is in some cases dramatic. Patient: A 4-day old full-term neonate was admitted to the intensive care unit with severe congestive heart failure and metabolic acidosis. Mechanical ventilation was initiated and dobutamine administered because of poor systolic function. Continuous monitoring of blood pressure revealed severe arterial hypertension (30 to 40 mm Hg above the 95th percentile). Ultrasonography showed an echogenic left kidney with normal perfusion. Laboratory examinations revealed a raised peripheral renin activity, thrombocytopenia, slightly raised d-dimers, a microhematuria and mild proteinuria. After resolution of hypertension under therapy with an ACE-inhibitor, a MAG3 renal scan showed complete absence of renal function on the left side. Renal artery stenosis was excluded by venous transcardial angiography. Under therapy with Captopril, the patient was discharged and followed up for 8 months. He is developing normally with normal serum creatinine (0.4 mg/dl), but low renal function (17%) of the left side as assed by DMSA-scan and compensatory right kidney hypertrophy are observed. Discussion: Diagnosis and treatment of neonatal hypertension are discussed with respect to the proposed case. After exclusion of other causes we conclude that a perinatal microangiopathic event may have lead to the renal lesions with malignant renovascular hypertension.