[Pathological and clinical correlations in renal AA amyloidosis: A Moroccan series of 30 cases]

The Clinical Features and Outcomes of Renal Amyloidosis in Tunisia

Systemic amyloidosis is a rare disease characterized by clinical polymorphism. Indeed, the kidney is the most common organ involved and represents a real turning point in the disease. We aimed to determine the clinicopathological prognostic factors of renal amyloidosis (RA). We conducted a retrospective study including 40 cases with biopsy-proven RA collected in our department over a period of 10 years. Biochemical, demographic, and clinicopathological findings at diagnosis, as well as the follow-up data, were evaluated for each patient. The prevalence of amyloidosis was 2.7 per 100 nontransplant renal biopsies. The mean age at presentation was 55.5 ± 15.6 years with a male-to-female ratio of 1.85. The diagnosis of RA was confirmed by a renal biopsy in 85% of cases. Amyloid A (AA) amyloidosis was the most common type of amyloidosis (65%), and chronic infections ranked first in the panel of etiologies (41%). Amyloid light chain amyloidosis was mainly associated with multiple myeloma (57%). The median patient survival was 59 months versus 12 months for kidney survival. Age and extrarenal localization were independent predictors of mortality, whereas renal failure at presentation significantly influenced renal survival. The results of our study emphasize the rarity but also the severity of RA. AA amyloidosis was the most common type identified, which was mainly caused by chronic infections. Prevention remains the best solution until we can achieve therapeutic advances in inflammatory diseases.

[Renal amyloidoses in nephrology]

The purpose of this study was to investigate the epidemiological, evolutionary and clinical features of the renal amyloidosis and to identify poor prognostic factors. We conducted a retrospective study focusing on all patients hospitalized for renal amyloidosis between January 2013 and December 2014. The diagnosis was confirmed by renal puncture-biopsy or by biopsy of minor salivary glands. We collected data from 25 patients, 17 men and eight women, with an average age of 47.2 ± 18 years. Hospitalization rate and prevalence were 2.4% and 12.5 cases/year respectively. On admission, nephrotic syndrome was detected in 100% of cases and renal failure in 68% of cases. Proteinuria was ≥6g/24h in 60% of cases. Digestive symptoms (n=14), cardiac symptoms (n=10) and arterial hypotension (n=11) were the other manifestations. Infectious and inflammatory diseases were the main causes found (60%). Tuberculosis alone accounted for 20%. After a mean follow-up period of 219.5 days, chronic renal failure was found in 16 cases (64%), including 11 cases with end-stage disease (44%). Six patients died. Renal insufficiency at the time of diagnosis, the worsening of renal function and readmission were associated with a risk for chronic terminal renal failure (p: 0.03-0.04). Cardiac damage, the readmission and proteinuria ≥6g/24h were factors associated with the risk of mortality (p< 0.03). Renal failure, cardiac damage, proteinuria ≥6g/24h and readmission were the main factors for poor prognosis in this cohort.