[Renal oncocytoma in pregnancy--an unusual presentation of secondary hypertension]

Renal oncocytoma accounts for 5-7% of primary renal neoplasms. It is usually, diagnosed in asymptomatic patients and is characterized by a benign behavior without invasion of adjacent tissues or metastasis. Diagnosis during pregnancy is uncommon and to date there have been only a few cases reported in the literature.

The authors present the case of a 32-year-old nulliparous woman with uncontrolled hypertension diagnosed at seven weeks gestation. She was referred to our institution at 24 weeks with superimposed pre-eclampsia complicated by acute pulmonary edema and hemodynamic instability requiring mechanical ventilatory support, fetal growth restriction and stillbirth. Etiological study of the hypertensive disorder performed in the postpartum period was consistent with renal oncocytoma.

The clinical behavior of renal oncocytoma remains poorly characterized during pregnancy and may lead to an adverse maternal and fetal outcome despite its theoretically benign behavior. It is essential to exclude a possible secondary cause of hypertension in cases that are difficult to control.