Key Information
Abstract
Objectives: Proteinuria, amyloidosis, and kidney failure are the main long-term renal complications of familial Mediterranean fever (FMF). This study assesses their risk factors, independent of ethnicity or residence.
Material and methods: Patients' data were drawn from the International AIDA Network registry for monogenic autoinflammatory diseases.
Results: A total of 598 FMF patients were enrolled, with 80 having proteinuria, 61 amyloidosis, and 25 kidney failure. At multivariate regression analysis, proteinuria was associated with out-of-flares thrombocytosis (OR: 4.78, 95%CI 1.54-14.8, p=0.007), increased out-of-flares erythrocyte sedimentation rate (ESR) (OR: 2.7, 95%CI 1.3-5.6, p=0.008), homozygous M694V mutation (OR: 2.27, 95%CI 1.1-4.66, p=0.025), and heterozygous M694V mutation (OR: 0.29, 95%CI 0.09-0.86, p=0.026); amyloidosis was associated with the disease duration (OR: 1.034, 95% CI1.004-1.065, p=0.027), during-flares anemia (OR: 2.9, 95%CI 1.18-7.19, p=0.021), out-of-flares leukocytosis (OR: 7.47, 95%CI 1.6-34.7, p=0.01), increased out-of-flares ESR (OR: 3.6, 95%CI 1.48-8.81, p=0.005), and heterozygous M694V mutation (OR: 0.18, 95%CI 0.035-0.9, p=0.04); kidney failure was associated with the age at diagnosis (1.04, 1.0003-1.19, p=0.048), the disease duration in years (OR: 1.07, 95%CI 1.02-1.12, p=0.005), attack frequency per year (OR: 1.04, 95%CI 1.007-1.076, p=0.019), anemia out-of-flares (OR: 4.7, 95% CI: 1.004-22.1, p=0.049), and out-of-flares leukocytosis (OR: 25.8, 95%CI 2.75-242, p=0.004). The intraclass correlation coefficient related to ethnicity and country of residence was 6.7% and 6.8% for amyloidosis, respectively, and 0% for proteinuria and kidney failure.
Conclusions: FMF patients with older age at diagnosis, longer disease duration, anemia, leukocytosis, thrombocytosis, elevated ESR, and homozygous M694V mutation are at higher risk of kidney complications.
Keywords: FMF; complications; kidney; outcome; prognosis.