Recurrence of DNAJB9-Positive Fibrillary Glomerulonephritis After Kidney Transplantation: A Case Series
AMERICAN JOURNAL OF KIDNEY DISEASES
Authors: El Ters, Mireille; Bobart, Shane A.; Cornell, Lynn D.; Leung, Nelson; Bentall, Andrew; Sethi, Sanjeev; Fidler, Mary; Grande, Joseph; Hernandez, Loren Herrera; Cosio, Fernando G.; Zand, Ladan; Amer, Hatem; Fervenza, Fernando C.; Nasr, Samih H.; Alexander, Mariam P.
Abstract
Rationale & Objective: Fibrillary glomerulonephritis (FGN) is a rare glomerular disease that often progresses to kidney failure requiring kidney replacement therapy. We have recently identified a novel biomarker of FGN, DnaJ homolog subfamily B member 9 (DNAJB9). In this study, we used sequential protocol allograft biopsies and DNAJB9 staining to help characterize a series of patients with native kidney FGN who underwent kidney transplantation. Study Design: Case series. Setting & Participants: Between 1996 and 2016, kidney transplantation was performed on 19 patients with a reported diagnosis of FGN in their native/transplant kidneys. Using standard diagnostic criteria and DNAJB9 staining, we excluded 5 patients (4 atypical cases diagnosed as possible FGN and 1 donor-derived FGN). Protocol allograft biopsies had been performed at 4, 12, 24, 60, and 120 months posttransplantation. DNAJB9 immunohistochemistry was performed using an anti-DNAJB9 rabbit polyclonal antibody. Pre- and posttransplantation demographic and clinical characteristics were collected. Summary statistical analysis was performed, including nonparametric statistical tests. Observations: The 14 patients with FGN had a median posttransplantation follow-up of 5.7 (IQR, 2.9-13.8) years. 3 (21%) patients had recurrence of FGN, detected on the 5- (n = 1) and 10-year (n = 2) allograft biopsies. Median time to recurrence was 10.2 (IQR, 5-10.5) years. Median levels of proteinuria and iothalamate clearance at the time of recurrence were 243 mg/d and 56 mL_/min. The remaining 11 patients had no evidence of histologic recurrence on the last posttransplantation biopsy, although the median time of follow-up was significantly less at 4.4 (IQR, 2.9-14.4) years. 3 (21%) patients had a monoclonal protein detectable in serum obtained pretransplantation; none of these patients had recurrent FGN. Limitations: Small study sample and shorter follow-up time in the nonrecurrent versus recurrent group. Conclusions: In this series, FGN had an indolent course in the kidney allograft in that detectable histologic recurrence did not appear for at least 5 years posttransplantation.
Integrated Analysis of Whole Exome Sequencing and Copy Number Evaluation in Parkinson's Disease
SCIENTIFIC REPORTS
Authors: Al Yemni, Eman; Monies, Dorota; Alkhairallah, Thamer; Bohlega, Saeed; Abouelhoda, Mohamed; Magrashi, Amna; Mustafa, Abeer; AlAbdulaziz, Basma; Alhamed, Mohamed; Baz, Batoul; Goljan, Ewa; Albar, Renad; Jabaan, Amjad; Faquih, Tariq; Subhani, Shazia; Ali, Wafa; Shinwari, Jameela; Al-Mubarak, Bashayer; Al-Tassan, Nada
Abstract
Genetic studies of the familial forms of Parkinson's disease (PD) have identified a number of causative genes with an established role in its pathogenesis. These genes only explain a fraction of the diagnosed cases. The emergence of Next Generation Sequencing (NGS) expanded the scope of rare variants identification in novel PD related genes. In this study we describe whole exome sequencing (WES) genetic findings of 60 PD patients with 125 variants validated in 51 of these cases. We used strict criteria for variant categorization that generated a list of variants in 20 genes. These variants included loss of function and missense changes in 18 genes that were never previously linked to PD (NOTCH4, BCOR, ITM2B, HRH4, CELSR1, SNAP91, FAM174A, BSN, SPG7, MAGI2, HEPHL1, EPRS, PUM1, CLSTN1, PLCB3, CLSTN3, DNAJB9 and NEFH) and 2 genes that were previously associated with PD (EIF4G1 and ATP13A2). These genes either play a critical role in neuronal function and/or have mouse models with disease related phenotypes. We highlight NOTCH4 as an interesting candidate in which we identified a deleterious truncating and a splice variant in 2 patients. Our combined molecular approach provides a comprehensive strategy applicable for complex genetic disorders.