Abstract: PUB395
A Rare Late Presentation of Galloway Mowat Syndrome (GAMOS) with Membranous Nephropathy
Session Information
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Sasidharan, Sandeep Raja, SUNY Downstate Health Sciences University, New York City, New York, United States
- Jatoi, Tahir Ahmed, SUNY Downstate Health Sciences University, New York City, New York, United States
- Yeboah, Eugene Kwabena, SUNY Downstate Health Sciences University, New York City, New York, United States
- Saggi, Subodh J., SUNY Downstate Health Sciences University, New York City, New York, United States
Introduction
GAMOS is a rare autosomal recessive disorder initially described in 1968. It is characterized by various neurological and renal abnormalities, with heterogeneous clinical and histopathological phenotypes reported. Renal presentations range from asymptomatic proteinuria to SRNS. Here, we present a unique case of GAMOS diagnosed in an elderly black male with a WDR73 gene deletion.
Case Description
A 64-year-old male with recurrent DVT on AC, UC, HTN, and CKD. He presented with worsening proteinuria due to membranous nephropathy despite being on Tacrolimus and low-dose steroids along with enalapril. He complained of increased urinary frequency with frothing. He was vitally stable and exam unremarkable. Labs were creat of 1.0, alb 3.5, UPCR 2.8, C3 127, C4 41, urinalysis showed protein >500 and rest were negative. The genetic test was negative for APOL1 and positive for WDR73 gene deletion. Biopsy showed 5/25 globally sclerosed glomeruli, with 20% mild to moderate interstitial fibrosis. IF had a granular pattern along capillary walls for 3+ IgG, 1+C3, 2+ kappa, and 2+ lambda light chains, rest negative, including M-type PLA2R. EM showed a markedly irregular contour of BM with subepithelial and intramembranous electron-dense deposits. Diagnosed as membranous glomerulonephritis stage 2-3, PLA2R negative. THSD7A and NELL-1 antigens are pending. Patient was advised Rituximab infusion and will follow up with his nephrologist in Barbados.
Discussion
Homozygous mutations in WDR73 were first implicated in patients with GAMOS in 2014. Recently, via whole exon sequencing and high-throughput exon sequencing, mutations were identified in the Kinase, Endopeptidase, and Other Proteins of Small Size (KEOPS) complex genes responsible for GAMOS. The complex comprises four subunits: LAGE3, OSGEP, TP53RK, and TPRKB. A fifth member of the complex, C14ORF142, has been identified recently. Our patient has a deletion of the WDR73 gene and presents late in life with only proteinuria. The reported life expectancy was between 0.3 to 28 years of age, with most individuals not surviving beyond their teenage years, with the commonest causes of death being nephrotic syndrome or seizures. We aim to contribute to the existing knowledge base by presenting the first known case of GAMOS in an elderly male.