A 10-month-old girl with nephrotic proteinuria, hypercholesterolaemia, hypoalbuminaemia, hyponatraemia, hypokalaemia, hypocalcaemia, metabolic alkalosis, normal auscultatory blood pressure on multiple occasions, and an enlarged left kidney on ultrasound, was referred to hospital. A left-kidney biopsy showed normal glomeruli with mild mesangial proliferation and the thickening of arteriolar walls. Glucocorticoid therapy was started. A further course was complicated by vomiting, irritation, pulsatile fontanel, and an enlarged ventricular system on ultrasound. A ventriculoperitoneal shunt was inserted but, during anaesthesia, repeated automated, oscillometric measurements revealed blood pressure of 220/120 mmHg. Intravenous antihypertensive treatment lowered the blood pressure to 110–120/70 mmHg, with a decrease in proteinuria. A CT abdominal angiography revealed left-renal-artery stenosis, a reduced right kidney and an enlarged left kidney, with foci of a post-infarct area in the lower pole. The patient was referred to a tertiary-care hospital. Renal scintigraphy showed that the right-kidney function had decreased to 6%. A right nephrectomy was performed but, due to persistent arterial hypertension, oral antihypertensive treatment was intensified. Microscopic analysis of the removed right kidney revealed relatively normal glomeruli and fibromuscular dysplasia in the right-renal-artery specimen. Oral antihypertensive therapy based on an angiotensin-converting enzyme inhibitor and a calcium-channel blocker continued after surgery allowed the attaining of normotension, the gradual normalisation of proteinuria and metabolic abnormalities, and an improvement in the left-kidney function. This case shows that auscultatory blood-pressure measurements in small children and incorrect interpretation of the obtained test results can lead to the erroneous misdiagnosis of hypertensive crisis, with dramatic consequences.A 10-month-old girl with nephrotic proteinuria, hypercholesterolaemia, hypoalbuminaemia, hyponatraemia, hypokalaemia, hypocalcaemia, metabolic alkalosis, normal auscultatory blood pressure on multiple occasions, and an enlarged left kidney on ultrasound, was referred to hospital. A left-kidney biopsy showed normal glomeruli with mild mesangial proliferation and the thickening of arteriolar walls. Glucocorticoid therapy was started. A further course was complicated by vomiting, irritation, pulsatile fontanel, and an enlarged ventricular system on ultrasound. A ventriculoperitoneal shunt was inserted but, during anaesthesia, repeated automated, oscillometric measurements revealed blood pressure of 220/120 mmHg. Intravenous antihypertensive treatment lowered the blood pressure to 110-120/70 mmHg, with a decrease in proteinuria. A CT abdominal angiography revealed left-renal-artery stenosis, a reduced right kidney and an enlarged left kidney, with foci of a post-infarct area in the lower pole. The patient was referred to a tertiary-care hospital. Renal scintigraphy showed that the right-kidney function had decreased to 6%. A right nephrectomy was performed but, due to persistent arterial hypertension, oral antihypertensive treatment was intensified. Microscopic analysis of the removed right kidney revealed relatively normal glomeruli and fibromuscular dysplasia in the right-renal-artery specimen. Oral antihypertensive therapy based on an angiotensin-converting enzyme inhibitor and a calcium-channel blocker continued after surgery allowed the attaining of normotension, the gradual normalisation of proteinuria and metabolic abnormalities, and an improvement in the left-kidney function. This case shows that auscultatory blood-pressure measurements in small children and incorrect interpretation of the obtained test results can lead to the erroneous misdiagnosis of hypertensive crisis, with dramatic consequences
