Olga Kukuy1, Avi Livneh, Aharon Ben-David, Juri Kopolovic, Alexander Volkov, Yael Shinar, Eliezer Holtzman, Dganit Dinour, Ilan Ben-Zvi. 1. From the Institute of Nephrology and Hypertension, Sheba Medical Center, Tel Hashomer; Heller Institute of Medical Research, Sheba Medical Center, Tel Hashomer; Department of Pathology, Sheba Medical Center, Tel Hashomer; Department of Pathology, Hadassah-Hebrew University Medical Center, Jerusalem; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv; The Dr. Pinchas Borenstein Talpiot Medical Leadership Program 2012, Chaim Sheba Medical Center, Tel Hashomer, Israel.
Abstract
OBJECTIVE: Reactive (AA) amyloidosis may complicate familial Mediterranean fever (FMF), the prototype of autoinflammatory diseases. Thus, proteinuria in FMF is commonly viewed as resulting from amyloidosis, and kidney biopsy is deemed superfluous. However, nephropathy other than amyloidosis has been described in FMF, but its rate and distinctive characteristics are unknown. Our aim was to determine the rate and underlying pathology of FMF-related nonamyloidotic proteinuria and compare its clinical course, demographic, and genetic features to those of FMF-amyloid nephropathy. METHODS: This study is a retrospective analysis of data from patients with FMF undergoing kidney biopsy for proteinuria above 0.5 g/24 h, over 10 years (2001-2011). Clinical, laboratory, genetic, and pathology data were abstracted from patient files. Biopsies were viewed by an experienced pathologist, as necessary. RESULTS: Of the 25 patients referred for kidney biopsy, only 15 (60%) were diagnosed with amyloid kidney disease (AKD), and 10 were diagnosed with another nephropathy. The AKD and nonamyloid kidney disease (NAKD) groups were comparable on most variables, but showed distinct characteristics with regard to the degree of proteinuria (6.45 ± 4.3 g vs 2.14 ± 1.6 g, p = 0.006), rate of severe FMF (14 vs 5 patients, p = 0.022), and rate of development of end stage renal disease (73.3% vs 20%, p = 0.015), respectively. CONCLUSION: NAKD is common in FMF and, compared to amyloidosis, it is featured with milder course and better prognosis. Contrary to common practice, it is highly recommended to obtain a kidney biopsy from patients with FMF and proteinuria more than 0.5 g/24 h.
OBJECTIVE: Reactive (AA) amyloidosis may complicate familial Mediterranean fever (FMF), the prototype of autoinflammatory diseases. Thus, proteinuria in FMF is commonly viewed as resulting from amyloidosis, and kidney biopsy is deemed superfluous. However, nephropathy other than amyloidosis has been described in FMF, but its rate and distinctive characteristics are unknown. Our aim was to determine the rate and underlying pathology of FMF-related nonamyloidotic proteinuria and compare its clinical course, demographic, and genetic features to those of FMF-amyloid nephropathy. METHODS: This study is a retrospective analysis of data from patients with FMF undergoing kidney biopsy for proteinuria above 0.5 g/24 h, over 10 years (2001-2011). Clinical, laboratory, genetic, and pathology data were abstracted from patient files. Biopsies were viewed by an experienced pathologist, as necessary. RESULTS: Of the 25 patients referred for kidney biopsy, only 15 (60%) were diagnosed with amyloid kidney disease (AKD), and 10 were diagnosed with another nephropathy. The AKD and nonamyloid kidney disease (NAKD) groups were comparable on most variables, but showed distinct characteristics with regard to the degree of proteinuria (6.45 ± 4.3 g vs 2.14 ± 1.6 g, p = 0.006), rate of severe FMF (14 vs 5 patients, p = 0.022), and rate of development of end stage renal disease (73.3% vs 20%, p = 0.015), respectively. CONCLUSION: NAKD is common in FMF and, compared to amyloidosis, it is featured with milder course and better prognosis. Contrary to common practice, it is highly recommended to obtain a kidney biopsy from patients with FMF and proteinuria more than 0.5 g/24 h.
Authors: Sarah Wente-Schulz; Marina Aksenova; Atif Awan; Cahyani Gita Ambarsari; Francesca Becherucci; Francesco Emma; Marc Fila; Telma Francisco; Ibrahim Gokce; Bora Gülhan; Matthias Hansen; Timo Jahnukainen; Mahmoud Kallash; Konstantinos Kamperis; Sherene Mason; Antonio Mastrangelo; Francesca Mencarelli; Bogna Niwinska-Faryna; Michael Riordan; Rina R Rus; Seha Saygili; Erkin Serdaroglu; Sevgin Taner; Rezan Topaloglu; Enrico Vidal; Robert Woroniecki; Sibel Yel; Jakub Zieg; Lars Pape Journal: BMJ Open Date: 2021-05-28 Impact factor: 2.692