[Show abstract][Hide abstract] ABSTRACT: Background
Immunoglobulin (Ig) A nephropathy (IgAN) is characterized by mesangial deposits of IgA1 and C3, often with co-deposits of IgG. We attempted to clarify the clinical significance of mesangial IgG deposition in patients with IgAN.
We retrospectively reviewed 57 patients who were diagnosed with IgAN on the basis of pathological examination of renal biopsy specimens obtained between October 2006 and December 2010. Subjects were divided into two groups: IgA+IgG deposition (IgA-IgG) group (n = 29) and IgA deposition alone (IgA) group (n = 28). The study outcome was complete remission (CR), defined as negative proteinuria by dipstick urinalysis and urinary erythrocytes of less than 1–4/high-power field.
Proteinuria was greater in the IgA-IgG group than the IgA group (1.1 ± 0.8 vs. 0.7 ± 0.6 g/day, Mann–Whitney U test, P = 0.042). Capillary wall IgA deposits were noted more frequently in the IgA-IgG group than the IgA group (59 vs. 11 %, Fisher’s exact test, P = 0.014). During the median follow-up period of 33.3 months (range 6–55 months) in the 57 patients, we observed CR in 24 cases (42.1 %). After the start of treatment, urinary abnormalities disappeared earlier in the IgA group than in the IgA-IgG group (log rank test, P = 0.012). Cox’s regression model showed that IgG deposition reduced the hazard ratio for CR (hazard ratio 0.35; 95 % confidence interval 0.14–0.82, P = 0.014). Therefore, IgG deposition is a risk factor for persistent urinary abnormalities.
Mesangial IgG deposition is associated with more severe clinical features in patients with IgAN.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this crossover comparison study is to elucidate the differences between the effects of a novel calcitriol analog, 22-oxacalcitriol, and calcitriol on parathyroid hormone (PTH) and bone mineral metabolism in hemodialysis patients with secondary hyperparathyroidism (SHPT). Twenty-three patients with moderate to severe SHPT were included in a random 2 x 2 crossover trial with two vitamin D analogs (12 weeks for each treatment). Two patients withdrew during the run-in period for personal reasons. Serum electrolyte, bone metabolic marker, intact PTH (iPTH) and whole PTH (wPTH) levels were measured periodically. The primary endpoint measure was a decrease in serum iPTH level, and the secondary outcome measures included changes in serum calcium (Ca), phosphate (P), and metabolic bone marker levels. Both treatments decreased iPTH and wPTH levels by similar degrees. Serum Ca, P, and Ca x P product levels at the end of each treatment were comparable and the frequencies of hypercalcemia and hyperphosphatemia were also similar during each treatment period. 22-Oxacalcitriol significantly decreased the levels of bone metabolic markers, namely, bone-specific alkaline phosphate, intact osteocalcin, pyridinoline, and cross-linked N-telopeptide of type I collagen, after a 12-week treatment. In contrast, calcitriol did not change any of the levels of bone metabolic markers. The present study showed that 22-oxacalcitriol is equally effective for PTH suppression, and Ca and P metabolism. In addition, 22-oxacalcitriol might have putative actions on bone remodeling independent of its PTH suppression. Further study is necessary to confirm the effects of 22-oxacalcitriol on bone metabolism in SHPT.
Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 07/2007; 11(3):202-9. DOI:10.1111/j.1744-9987.2007.00422.x · 1.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Secondary hyperparathyroidism (SHPT) leads not only to bone disorders, but also to cardiovascular complications in long-term dialysis patients. Conventional treatment with calcium (Ca) supplement, phosphate (P) binders and active vitamin D analogs lead in part to amelioration of SHPT, but are simultaneously associated with unacceptable side-effects, including hypercalcemia, hyperphosphatemia, and increased Ca x P products, which are the risk factors for cardiovascular disease in dialysis patients. Conventional treatment has been unable to facilitate the attainment of optimal management of SHPT proposed in the K/DOQI guidelines. Cinacalcet HCl (cinacalcet), a novel calcimimetic compound, restores the sensitivity of the Ca-sensing receptor in parathyroid cells, and decreases serum parathyroid hormone (PTH) without introducing hypercalcemia or hyperphosphatemia. Cinacalcet treatment enables a significant number of patients to achieve the K/DOQI guideline. Based on experimental data, calcimimetics could ameliorate cardiovascular calcification and remodeling in uremic rats with SHPT. Clinical trials have shown that cinacalcet significantly reduced the risks of parathyroidectomy, fracture and cardiovascular hospitalization among long-term dialysis patients with SHPT. Parathyroid intervention therapy (parathyroidectomy and percutaneous direct injection) is also a useful alternative. In the present article, we review novel therapeutic strategies for SHPT.
Therapeutic apheresis and dialysis: official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy 09/2006; 10(4):355-63. DOI:10.1111/j.1744-9987.2006.00389.x · 1.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Patients with chronic renal disease (CKD)almost always develop secondary hyperparathyroidism (SHPT) due to hypocalcemia, phosphate retention, and abnormalities in vitamin D (VD) metabolism. Concomitant decreases in VD receptor and calcium sensing receptor in the parathyroid glands render them more resistant to the action of VD and calcium, and accelerate parathyroid cell growth. Several types of bone diseases are known to occur in CKD patients. Excessive secretion of parathyroid hormone (PTH) due to SHPT causes high-turnover bone disease, called osteitis fibrosa. Among low-turnover bone disease (LTBD), osteomalacia which is characterized by calcification defect is often complicated with VD deficiency and/or aluminum accumulation. Recently, frequency of adynamic bone disease caused by PTH suppression, another type of LTBD, is increasing probably due to calcium salts as phosphate binder with or without VD treatment.