Renal involvement in systemic amyloidosis: an Italian collaborative study on survival and renal outcome.

BACKGROUND: Few data are available from large population-based studies on survival and renal outcome of patients with renal involvement and different types of systemic amyloidosis. METHODS: Two hundred and ninety of over 373 patients affected from systemic amyloidosis with renal involvement diagnosed in Italy between January 1995 and December 2000 were followed from diagnosis to death or until the last available clinical control. Eighty-three patients were excluded from analysis either because the amyloid type remained undetermined or they were lost at follow-up. Clinical and laboratory information was collected according to the different types of amyloidosis using a specific form which included renal function with 24 h proteinuria at diagnosis and at the end of follow-up, the type and the date of onset of dialysis and the kind of treatment they underwent. RESULTS: The median time of follow-up was 24 months in primary (AL) amyloidosis (range: 1-88 months), 16 months in AL with associated multiple myeloma (MM + AL: range 1-76 months), 30 months in reactive (AA) amyloidosis (range: 1-99 months) and 52 months in patients with familial forms (AF: range 14-82 months). Patients with AL showed a significantly shorter survival than AA. Despite no significant differences of renal outcome or survival on dialysis being observed between the two groups, a lower renal survival with a higher number of patients who progressed to end-stage renal disease (ESRD) was observed in patients with AA. Overall survival was markedly improved in patients with AL who underwent a specific therapy (conventional chemotherapy or autologous stem cell transplantation (ASCT)) even in the absence of a positive kidney response. Multivariate analysis showed cardiac involvement and specific therapy to significantly influence survival in AL whereas age, serum creatinine (sCr) and heart involvement significantly affected survival in AA. In both groups, sCr and heart involvement were the most relevant predictors for renal outcome, together with urinary protein excretion, in patients with AA. CONCLUSIONS: Our results show a worse survival in AL due to the higher prevalence of heart involvement in this group and emphasize that a specific therapy significantly prolongs survival and slows the progression of renal disease in patients with AL. We suggest that a late nephrological referral is likely the cause of the higher sCr found at presentation in patients with AA and probably accounts for the lower renal survival observed in the short term in these patients. At the time being, renal transplantation and ASCT are still rare therapeutic options for renal patients affected from systemic amyloidosis.

IgA nephropathy in systemic lupus erythematosus.

Renal involvement in systemic lupus erythematosus (SLE) is a typical manifestation of the disease. The occurrence of non-lupus nephritis in SLE patients has rarely been reported; we describe the case of a woman suffering from SLE and IgA nephropathy (IgAN). Although IgAN and lupus nephritis share some common physiopathological characteristics, their laboratory and histopathologic findings and the extra-renal clinical manifestations are different and support a different pathogenesis. Our case highlights the importance of renal biopsy in lupus patients with urinary alterations since a correct diagnosis would permit the most appropriate treatment to be started, thus avoiding unnecessary immunosuppressive treatments.

[Nutcracker syndrome: a difficult case of recurrent gross hematuria]. / Sindrome di nutcracker: una macroematuria intermittente di difficile diagnosi.

BACKGROUND: The Nutcracker Syndrome (NS) is an uncommon clinical condition caused by compression and entrapment of the renal vein (LRV) as it passes through the angle between the superior mesenteric artery (SMA) and the aorta (meso-aortic angle). Intermittent macrohematuria, left peripelvic and gonadal vein varices and aspecific abdominal pain may be common manifestations of this syndrome. CASE-REPORT: A 15-year-old white boy developed recurrent macrohaematuria in June 2002. He had a history of upper respiratory infection prior the first episode of gross hematuria followed by 4 other episodes of macrohematuria 'sine causa'. Blood pressure and renal function were normal. Routine laboratory tests showed only an increase in serum LDH levels (901 IU/L) with negative Coombs' test, both direct and indirect, and absence of schistocytes in the blood smear. Renal ultrasonography showed normal kidneys while an intravenous pyelography showed a 'minus' in the right ureter. For this reason, a cystoscopy and a retrograde pielography were performed but resulted normal. A renal biopsy was carried out because of the presence of one episode of post-infective macrohaematuria, but light microscopy and immunofluorescence examinations were found to be normal. Renal ultrasonography and Color Doppler ultrasonography (CD-USG) oriented our diagnosis towards NS. An abdominal computerised tomography (CT) scan confirmed that the LRV was compressed between the aorta and the SMA. CONCLUSIONS: NS cannot be diagnosed with routine diagnostic methods. Endoscopic and radiological methods may provide some clues for the presence of NS, while CD-USG may be considered to be the first level non-invasive method for diagnosis. The sensitivity and specificity of this test for diagnosing NS is reported as being 78% and 94%, respectively. The best treatment available for this syndrome is still being debated.