RESUMO
BACKGROUND: Secondary hyperparathyroidism (SHPT) is frequent in haemodialysis (HD) patients. Oral cinacalcet-hydrochloride (HCl) decreases parathyroid hormone (PTH); however, real-life PTH data, according to Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, are still lacking. Our goal is to assess the percentage of cinacalcet-HCl-treated HD patients with controlled SHPT (PTH <9× upper limit of the normal range) after 12 months (M12) of treatment. METHODS: This is a retrospective observational study in HD patients with SHPT treated by cinacalcet-HCl between 2005 and 2015 and dialysed in seven French HD centres using the same database (Hemodial™). RESULTS: The study included 1268 patients with a mean (standard deviation) follow-up of 21 ± 12 months. Their mean dialysis vintage was 4.3 ± 5.6 years. PTH values were available and exploitable at M12 in 50% of them (645 patients). Among these patients, 58.9% had controlled (mean PTH of 304 ± 158 pg/mL) and 41.1% uncontrolled SHPT (mean PTH of 1084 ± 543) at M12. At the baseline, patients with controlled SHPT were older (66 ± 15 versus 61 ± 17 years), and had lower PTH (831 ± 346 versus 1057 ± 480 pg/mL) and calcaemia (2.18 ± 0.2 versus 2.22 ± 0.19 mmol/L) than uncontrolled patients. In multivariate analysis, these three factors still remained significantly associated with controlled SHPT. CONCLUSION: In this real-life study, 41.1% of HD patients with SHPT treated with cinacalcet-HCl remained with a PTH above the KDIGO recommended target after 12 months of treatment. Apart from the possibility of non-compliance, the severity of SHPT appears to be a major factor determining the response to cinacalcet-HCl treatment, reinforcing the importance of treating SHPT at earlier stages.
RESUMO
BACKGROUND: The clinical relevance of distinguishing two types of glomerulonephritis (GN) with non-amyloid organized immunoglobulin (Ig) deposits-fibrillary GN (FGN) and immunotactoid (microtubular) GN (IT/MTGN)-on the basis of ultrastructural organization, is debated. METHODS: Twenty-three patients with organized glomerular Ig deposits were classified into two groups based on the fibrillar or microtubular ultrastructural appearance of the deposits. Kidney biopsy samples were studied by immunofluorescence microscopy, using anti-light chain conjugates (all cases) and anti-IgG subclass conjugates (13 patients). In each group, we studied clinicopathological features, associated monoclonal gammapathy (detected by immunoelectrophoresis and/or immunoblot) or B-cell lymphoproliferative disease, effects of chemotherapy and long-term renal outcome. RESULTS: In 14 IT/MTGN and 9 FGN patients, clinical symptoms [hypertension, nephrotic syndrome (NS) and hematuria] and the mean diameters of the substructures were similar. In 13 IT/MTGN patients, glomerular (IgG1, 2 or 3) deposits were monotypic (kappa, 7 cases; lambda, 6 cases). Glomerular deposits were associated with a monoclonal Ig of the same isotype in eight patients, detected in the serum (5 cases), and/or in the cytoplasm of lymphocytes (4 cases), and with lymphoproliferative disease in seven patients. The ultrastructural features of monoclonal Ig inclusions in lymphocytes were similar to those of glomerular microtubular deposits. In contrast, none of the FGN patients presented lymphoplasmocytic proliferation or paraproteinemia. Glomerular Ig deposits were polyclonal in eight cases and contained IgG4 in all three cases studied. Although patient and renal survival did not differ significantly between the two groups, chemotherapy led to remission of NS in ten IT/MTGN patients, with parallel improvement in hematological parameters. CONCLUSIONS: The identification of ultrastructural patterns in these nephropathies is important. GN with organized microtubular monoclonal deposits (GOMMID) probably accounts for a large proportion of immunotactoid (microtubular) GN cases.