Juxtaglomerular cell tumour of the kidney: a rare cause of resistant hypertension

Abstract

Summary Juxtaglomerular cell tumour (JGCT) is an unusually encountered clinical entity. A 33-year-old man with severe long-standing hypertension and hypokalaemia is described. The patient also suffered from polyuria, polydipsia, nocturia and severe headaches. On admission, laboratory investigation revealed hypokalaemia, kaliuresis, high aldosterone and renin levels, and the abdomen CT identified a mass of 4 cm at the right kidney. Kidney function was normal. Following nephrectomy, the histological investigation revealed the presence of a JGCT. Immunostaining was positive for CD34 as well as for smooth muscle actin and vimentin. Following surgery, a marked control of his hypertension with calcium channel blockers and normalization of the serum potassium, renin or aldosterone levels were reached. According to our findings, JGCT could be included in the differential diagnosis of secondary hypertension as it consists of a curable cause. The association of JGCT with hypertension and hypokalaemia focusing on the clinical presentation, diagnostic evaluation and management is herein discussed and a brief review of the existing literature is provided. Learning points Juxtaglomerular cell tumours (JGCT), despite their rarity, should be included in the differential diagnosis of secondary hypertension as they consist of a curable cause of hypertension. JGCT could be presented with resistant hypertension along with hypokalaemia, kaliuresis and metabolic alkalosis. Early recognition and management can help to prevent cardiovascular complications. Imaging (enhanced CT scans) may be considered as the primary diagnostic tool for the detection of renal or JGCT. For the confirmation of the diagnosis, a histopathologic examination is needed.

Renal venous sampling assisted the diagnosis of juxtaglomerular cell tumor: a case report and literature review

“…Juxtaglomerular cell tumor originates from the smooth muscle cells of the afferent arteriole within the juxtaglomerular apparatus. These tumors are consistently benign neoplasms and secrete the enzyme renin, resulting in the hyperactivation of the renin–angiotensin–aldosterone system ( 3 ). Nevertheless, some non-renal malignant tumors, such as pancreatic cancer and ovarian cancer, can also secrete excessive renin ( 4 , 5 ).…”

Diagnostic challenges in patients with reninomas and extrarenal renin‐producing tumours

“…Reninomas can appear isodense compared to the renal cortex on non-enhanced CT images and are in other cases undetectable. 5,20,21 Even with the use of contrast enhanced CT scan, reninomas may be difficult to detect. Some reninomas display low enhancement compared to the renal parenchyma and can even be mistaken for a cyst, 22,23 possibly explained by local vasoconstrictor effect of angiotensin II and/or a lack of neovascular development within the tumour.…”

“…To identify the tumour, a contrast enhanced CT scan was used first in two of the cases and MRI in one. Reninomas can appear isodense compared to the renal cortex on non‐enhanced CT images and are in other cases undetectable 5,20,21 . Even with the use of contrast enhanced CT scan, reninomas may be difficult to detect.…”

Reninoma: A Case of a Small Renal Mass Removed with Robotic-Assisted Surgery

“…Juxtaglomerular cell tumors secreted an excessive amount of renin, which causes secondary hyperaldosteronism and consequently hypertension. 5,6 Due to its rarity, the time it takes to reach a confirmed diagnosis is often extended.…”