Amiloride, a drug often used to treat hypertension and congestive heart failure, was shown to improve kidney function in a patient with chronic kidney disease stage 2 with Alport syndrome, researchers at Hospital Britanico de Buenos Aires, Argentina, reported.
The study, “Podocyturia: A Clue for the Rational Use of Amiloride in Alport Renal Disease,” was published in the journal Case Reports in Nephrology.
People with Alport syndrome are advised to take certain, if limited, steps to delay loss of kidney function, such as keeping a healthy weight, controlling their blood pressure and salt intake, avoiding tobacco, and, if needed, medications with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers.
Because Alport syndrome is hereditary, these recommendations are most often followed by people familiar with this disease. Since all patients develop end-stage kidney disease early in adulthood, however, even those who are asymptomatic are in need of early and effective interventions, the study reported.
Researchers followed a 25-year-old man with a family background of Alport disease. Analyses showed that he had normal kidney function, microhematuria (presence of very small amounts of blood in the urine), and mild proteinuria (presence of proteins in the urine). However, the team also analyzed podocyturia, that is, the presence of podocytes (cells that compose the filtration barrier of the kidneys) in the urine, given that the presence of this cells rise as Alport syndrome progresses. Indeed, the patient’s podocyturia was higher than expected.
He was prescribed amiloride (5 mg/day orally) and, after three months, the treatment had reduced the presence of proteins and cells in his urine. This result suggests that podocyte detachment in Alport syndrome may ease with amiloride use, delaying the development of end-stage kidney disease. The mechanisms by which this drug exerts its beneficial effects, however, remain elusive.
“In summary, the decrease in podocyturia displayed by our patient after amiloride administration may suggest that podocyte molecular pathways may be involved in the pathogenesis of podocyturia and the development of proteinuria in Alport syndrome,” the authors concluded. “Due to the lack of specific treatments, amiloride may prove a useful, nonexpensive drug to be employed in Alport syndrome in order to delay kidney disease progression, mainly by the preservation of the podocyte population.”