Trends of elevated parathormone serum titers in hemodialysis patients on intensive therapy for bone disease: a multicenter study

To determine the prevalence of controlled parathyroid hormone (PTH) serum levels with intensified therapy for chronic kidney disease mineral and bone disorder (CKD-MBD) in the dialysis population, we studied 563 chronic hemodialysis patients recruited from three different dialysis centers from three different major cities in the Kingdom of Saudi Arabia. The trend of the routine monthly chemistries related to CKD-MBD was evaluated besides the whole-molecule PTH serum levels over 28 months (January 2011 to April 2013). The cost ratios of the medications to the estimated dialysis total cost were calculated. There were 323 (57.4%) males in the study, and the mean age of the patients was 50.2±15.2 years; 371 (65.9%) patients were initiated on dialysis before 2011. The causes of the original kidney disease included diabetes mellitus in 163 (29%) patients. Parathyroidectomy was performed in 23 (4.1%) patients and only six (23%) patients underwent the operation during the study period; most of the parathyroidectomies (69%) were performed before 2011. The trend of the medians of monthly serum levels of calcium, phosphorus, albumin, bicarbonate, alkaline phosphatase, serum levels of PTH and vitamin D25 assays showed better control of the levels with time. The added cost of cinacalcet was more significant than the other drugs, including vitamin D and phosphate binders, but the cost was minimal in comparison with the whole dialysis bill. The ratios of the discontinuation rates to the total patient-months of treatment for the different drugs were in the range of 3-4% and mostly due to transient overdosing of medications. We conclude that the trends of the median serum levels of PTH and related minerals in the CKD patients in our dialysis patients suggested a good inclination toward control and prevention of the vascular calcifications prevalent in the CKD-MBD. The popularity of use of new drugs such as cinacalcet is promising and does not seem to add much to the current out-patient cost of chronic dialysis.

Rituximab as a rescue therapy in patients with glomerulonephritis

To evaluate the use of rituximab in the treatment of severe glomerulonephritis (GN) in order to prevent progression of kidney disease toward the end stage, we designed a multicenter, retrospective study in Saudi Arabia about the efficacy and safety of the use of "off label" rituximab in a variety of severe refractory GN to conventional treatment and the progression of kidney disease for at least one year of follow-up. All the patients had kidney biopsies before treatment with rituximab, and proteinuria and glomerular filtration rate (GFR) were followed-up for the period of the study. The immediate side-effect at the time of administration of rituximab included itching in three patients, hypotension in one patient and anaphylaxis in one patient (dropped out from the study). After the administration of rituximab in 42 patients and during the first six months of therapy, 16 (38%) patients had complete remission (CR), 13 (31%) patients had partial remission (PR) and 13 (31%) patients had no remission. The mean follow-up period for the patients was 19.0 ± 6.97 months (median 18.0 months). The long-term follow-up during the study period disclosed a good hospitalization record for almost all of the patients. Membranous GN (MGN) was the largest group in the cohort (58% of the patients), and we observed CR and PR in 40% and 28% of them, respectively, which was comparable with the previous experience with rituximab in MGN patients with more CR than PR in our cohort. We conclude that our study suggests the safety and efficacy of the use of rituximab in patients with refractory GN and that larger and long-term prospective studies are required to define the role of rituximab in the different categories of these diseases.