<unk>  or<unk>  phenomena is a potentially reversible form of secondary arterial hypertension caused by external compression of the renal parenchyma by some perirenal process. Any process that causes mass effect can be a potential cause of<unk> . Hematomas, urinomas, tumors, cysts, lymphoceles, and aneurysms have all been reported in the literature. The compression is believed to cause activation of the renin–angiotensin–aldosterone system (RAAS) via microvascular ischemia. Initially, the majority of cases that were described had a traumatic etiology but this has since shifted to iatrogenic causes. Since<unk>  is primarily a unilateral process, symptoms will differ depending on if the patient has native kidneys or not. In patients with only one solitary functioning kidney, the acute hypertension will also be accompanied by an acute decrease in renal function. In patients with one functioning kidney, prompt diagnosis and surgical treatment are needed to prevent irreversible kidney damage and restoration of kidney function. Medical treatment involves use of an angiotensin-converting enzyme inhibitor (ACEi) or an angiotensin receptor blocker (ARB) to control the hypertension.
Page kidney
Multicystic dysplastic kidney
Horseshoe kidney
Medullary sponge kidney
Crossed renal ectopia
Ectopic kidney
Glomerulocystic kidney disease
Medullary cystic kidney disease