Challenges in diagnosis of reninoma: three case reports and literature review

Reninoma is rare and very challenging to diagnose. It is characterized by excessive renin secretion that causes severe hypertension and occurs more frequently in young females. Here, we compare and analyze three cases, which were not initially considered reninoma, because there was no increase in plasma renin activity (PRA), patients had refractory hypertension, or were older.

In two cases, PRA is normal or decreased but the direct renin concentration (DRC) is elevated. The third is in an older man with ambiguous imaging assessments and no evident lateralization of renal vein renin levels.

Our findings suggest that the diagnosis of reninoma should not be completely excluded in patients with no elevated renin activity or refractory hypertension. In addition, a combination of blood tests and imaging analysis is highly recommended, and lateralization of renin levels is more applicable in cases where tumors are relatively small.