Kidney Function

Background: The optimal hemoglobin target and possible toxicity of epoetin therapy in hemodialysis patients are controversial. Previous studies suggest that African American patients use higher doses of epoetin and have better survival compared with white hemodialysis patients.Study Design: Retrospective longitudinal cohort.Setting & Participants: Epoetin-exposed incident hemodialysis patients (N = 12,733; African Americans, n = 4,801; white, n = 7,386) treated in Dialysis Clinic Inc facilities during 2000 to 2006.Predictors: Hemoglobin, epoetin, iron.Outcomes: Mortality, hospitalization.Measurements: Proportional hazards models with time-varying covariates.Results: Hemoglobin concentrations less than 10 g/dL in whites and less than 11 g/dL in African Americans were associated with increased mortality and hospitalization versus the referent hemoglobin level of 11 to 11.9 g/dL. Hemoglobin levels of 13 g/dL or greater in whites were associated with decreased noncardiovascular mortality. Six-month cumulative epoetin doses of 20,000 U/wk or greater were associated with increased mortality and hospitalization versus the referent group (8,000 to 12,499 U/wk). Epoetin doses less than 8,000 U/wk were associated with decreased risk. Higher epoetin doses were associated with increased mortality at hemoglobin concentrations of 10 to 12.9 g/dL and with increased hospitalization at all hemoglobin concentrations of 10 g/dL or greater. Higher epoetin doses were associated with increased mortality and hospitalization within each tertile of serum albumin concentration. These patterns did not differ by race.Limitations: Treatment-by-indication bias and unidentified confounders cannot be excluded. Small sample sizes in the highest and lowest hemoglobin strata decrease statistical power.Conclusions: Relationships between hemoglobin concentration and mortality differed between African Americans and whites. Additionally, the relationship of lower mortality with greater achieved hemoglobin concentration seen in white patients was observed for all-cause, but not cardiovascular, mortality. A higher cumulative epoetin dose was associated with worse outcomes, even in patients with albumin levels greater than 4 g/dL. There were no statistically significant interactions between race and epoetin dose. Further studies are needed to confirm and to define the mechanism of these findings.

Lupus nephritis is a major manifestation of systemic lupus erythematosus. Treatment with such immunosuppressive agents as corticosteroids or cyclophosphamide can decrease the progression of lupus nephritis; however, these agents have potentially severe adverse reactions. Therefore, the development of new drugs with fewer side effects is needed. Here, we report 2 patients with lupus that were treated successfully with retinoids. Initially, both patients were treated with 60 mg/d of prednisolone. However, nephrotic syndrome was not improved. Subsequently, treatment with 10 mg/d of all-trans-retinoic acid was started orally and elicited a good response, showing a decrease in proteinuria. Although additional controlled clinical studies are needed to confirm these findings, we suggest that therapy using retinoids may represent a novel approach to the treatment of patients with lupus nephritis.

Serum sickness after rabbit antithymocyte globulin administration has a reported incidence of 7% to 27% in kidney transplant recipients. We describe 4 patients with previous exposure to rabbits who developed serum sickness after primary rabbit antithymocyte globulin induction. All patients presented with jaw pain. Three of 4 patients treated with plasmapheresis and steroids had prompt recovery, and 1 patient treated with steroids had slower recovery. We performed a telephone interview of 214 patients who contemporaneously underwent transplantation between November 2006 and July 2008 regarding rabbit exposure. More than half the patients had some type of previous rabbit exposure. There was a suggestion that patients with serum sickness were exposed more frequently to rabbits than those without. Jaw pain appears to be a hallmark symptom, and treatment with plasmapheresis and steroids relieves symptoms more rapidly than steroids alone.