Co-occurring Usher syndrome Type 1 and Renal Failure.

Abstract

To describe a patient with a rare co-occurrence of Usher syndrome type 1C (USH1C) and renal disease, suspected to be secondary to Alport syndrome. Case report and literature review of cases with Usher syndrome and renal failure. Clinical examination, color fundus photography, visual field tests, electroretinography and whole exome sequencing were used to diagnose and document the patient's clinical presentation. An 18-year-old female with known history of congenital hearing loss and chronic renal failure, presents with progressive night and peripheral visual impairment suspicious for an inherited retinal disease. Visual field testing, fundus exam and electroretinography findings supported the diagnosis of Usher syndrome. Whole exome sequencing (WES) identified a novel homozygous frameshift variant (c.238del) in USH1C. WES also identified a homozygous COL4A3 variant of unknown significance, which may be responsible for concomitant Alport syndrome. By presenting this rare case of co-occurring Usher syndrome Type 1 and renal failure, we highlight the importance of conducting further investigations that could reveal an additional underlying etiology when these entities are present.