Osteitis condensans ilii: prevalence and characteristics of a neglected mimic of sacroiliitis

Clinical Rheumatology - Osteitis condensans ilii (OCI) is a benign condition characterised by triangular sclerosis of the iliac bone which may mimic radiographic sacroiliitis. Prevalence is...     

Catheter lock solutions: it's time for a change

In recent years, the number of patients on hemodialysis (HD) with central vascular catheters (CVCs) has grown. However, CVC use is often associated with an important risk for catheter related bloodstream infections (CR-BI) and inadequate dialysis due to flow problems. In this study, we reviewed alternative solutions to heparin for locking HD CVCs. Several experiences have demonstrated that trisodium citrate (TSC) (30-47%), citrate (4%) and taurolidine (1.35%) solutions are effective and safe for the prevention of CRBI, while heparin stimulates biofilm formation. High citrate (47%) concentrations can also provide significant advantages in reducing catheter clotting, but controlled studies with larger populations are necessary to confirm and to extend the use of such solutions in clinical practice. Side effects with high sodium citrate concentrations have been reported only immediately after locking, the symptoms are probably caused by a temporary drop in ionized calcium and magnesium, but it is evident that these solutions should only be used by skilled and authorized personnel, with a rigorous protocol.     

How to improve dialysis adequacy in patients with vascular access problems

Blood flow rate is a critical factor in the achievement of an adequate dialysis dose. The aim of this review is to evaluate the possibility of optimizing dialysis dose in terms of Kt/V in patients with reduced vascular access (VA) flow rate, considering effective blood flow (Qb eff), recirculation, access flow and hemodialyzer. In patients where the achievement of adequate blood flow rates are difficult to obtain and no surgical revision is necessary, to avoid under dialysis the increase in the treatment time should be the first choice solution. If such a solution is difficult for various reasons, a forced partial blood flow recirculation, especially in central venous catheters (CVCs) with reversed lines can be useful, on condition that the dialysis session is prolonged. The possibility of increasing the efficiency of dialysis through an increase in filter clearance has to be considered. Monitoring arterial pre-pump pressure (P asp) and optimizing ratio P asp/Qb eff during hemodialysis (HD) is one possible solution to improve blood flow rates, but it is necessary to educate and involve the staff. Recent developments in a new class of highly effective hemodialyzer due to dialysate distribution, has opened up interesting opportunities in terms of dialysis adequacy in patients with reduced VA flow rate.     

Sclerochoroidal calcifications associated with early-onset calcium pyrophosphate deposition disease

Clinical Rheumatology -     

Leptin and beta2-microglobulin kinetics with three different dialysis modalities

BACKGROUND: Leptin is a protein produced by fat cells and involved in body weight regulation. In patients with normal kidney function, leptin has been considered an independent predictor of cardiovascular events. In uremic patients, leptin in plasma serum was assumed to be associated with malnutrition, inflammation and atherosclerosis. Because of its molecular weight and characteristics, leptin can be considered as a protein-bound uremic retention solute. Some authors have reported the possibility of decreasing the serum leptin concentration with high flux membranes, but limited data are available on the elimination with medium-flux membranes or alternative dialysis strategies such as hemodiafiltration. METHODS: We evaluated the kinetics of leptin and beta2m in a study of 18 chronic hemodialysis patients using low-flux, medium-flux and high-flux biocompatible membranes, the last one used in hemodiafiltration (HDF). Blood samples for leptin and beta2m were collected pre- and post-treatment and 30 minutes after the end of treatment, over a 1-week period that included 3 dialysis sessions. Clearances of leptin and beta2m across the dialyzer were also determined directly from the arterial and venous blood concentrations 60 and 210 minutes after starting dialysis. RESULTS: At baseline, all groups showed similar leptin (18.8+/-4.4 ng/mL) and beta2m concentrations (29.2+/-7.1 ng/mL). After a single dialysis session, a reduction of both solutes was observed with HDF (39.8+/-1.9%, 78.1+/-4.9) and medium flux membranes (18.2+/-0.9%, 52.2+/-1.7%), whereas the concentrations remained unchanged with the low-flux membranes. After one-week period, a trend of reduction of plasma pre dialysis leptin and beta2m were observed with HDF and medium flux membranes. At 60 minutes, HDF showed the best instantaneous clearance across the filter for leptin (56.2+/-10.1 ml/min) and beta2m (75.3+/-4.4 ml/min). The magnitude of post dialysis rebound of leptin at 30 min was variable and strongly correlated with the instantaneous clearance of the solute (r2= 0.88). CONCLUSIONS: Leptin serum concentration can be influenced by dialysis modalities and membrane permeability; data on rebound suggest a multicompartimental kinetic of leptin similar to beta2m. Leptin removal, as measured by the reduction rate, can be considered as an index of dialysis efficiency for protein-bound uremic retention solutes.     

Azathioprine hypersensitivity: report of two cases and review of the literature

Azathioprine (AZA) is a widely-used drug in the treatment of different diseases such as vasculitis, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel diseases and in renal transplantation. Side effects of AZA can be classified as toxic, mainly dose related (myelosuppression and hepatotoxicity) and idiosyncratic, mainly dose independent. While the toxic effects are common and well documented, the hypersensitivity reactions are rare and it is not often easy to distinguish them from systemic sepsis or disease recurrence. We report two cases of AZA hypersensitivity occurring in patients with anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis each mimicking a vasculitis relapse or a septic complication of immunosuppression, as well as a review of the literature.