Systematic review of rituximab for autoimmune diseases: a potential alternative to intravenous immune globulin.

BACKGROUND: The anti-CD20 monoclonal antibody rituximab has immune-modulatory effects similar to intravenous immunoglobulin (IVIG). We performed a systematic review and meta-analysis to determine the efficacy and safety of rituximab in autoimmune diseases that are also treated with IVIG. STUDY DESIGN AND METHODS: The most common indications for immune modulation with IVIG, as identified from a 2012 regional audit in Canada, were chronic inflammatory demyelinating polyneuropathy (CIDP), immune thrombocytopenia (ITP), myasthenia gravis, multifocal motor neuropathy, Guillain-Barré syndrome, systemic lupus erythematosus (SLE), Sjogren's syndrome, and pemphigus vulgaris. We searched MEDLINE, EMBASE, and the Cochrane Library until July 2016 for studies evaluating rituximab in each of these conditions. The primary outcome in our meta-analysis was clinical response at 6 months as defined by disease-specific criteria in randomized trials. We also calculated pooled proportions of responders within disease types from observational studies. RESULTS: Ninety-five rituximab studies were identified: 86 were observational studies in patients with ITP (n = 1746), SLE (n = 1047), pemphigus vulgaris (n = 564), Sjogren's syndrome (n = 138), myasthenia gravis (n = 66), and CIDP (n = 31) and nine were randomized controlled trials (n = 992) in patients with ITP, SLE, and Sjogren's syndrome that compared rituximab with placebo plus standard of care. Among randomized trials, response rates were higher with rituximab (relative risk, 1.38; 95% confidence interval [CI], 1.05-1.83). The pooled proportion of rituximab responses ranged from 94% (95% CI, 88%-98%) for pemphigus vulgaris to 48% (95% CI, 30%-66%) for CIDP. Rituximab was generally well tolerated in observational studies although in the randomized trials, adverse events were more common in the rituximab group. CONCLUSION: Rituximab is an immune-modulating agent with biologic activity across many autoimmune conditions. Our data support the use of comparative trials with broad eligibility criteria to evaluate rituximab as an alternative to IVIG in autoimmune diseases.

A primer in pretransfusion testing.

Pretransfusion testing encompasses much more than testing a patient's sample in the laboratory. All aspects pertaining to this testing will be reviewed, from the clinician's order to the final step of when the blood product is ready to be issued to the clinical side from the laboratory. The importance of patient safety and positive outcomes will be stressed through discussion of positive patient identification and appropriate labelling in order to get the right product to the right patient at the right dose. Transfusion service does not stop in the laboratory; it is imperative that all who are involved in this service appreciate the significance of performing tasks accordingly to standards and regulations.

Severe hemolytic anemia post-renal transplantation produced by donor anti-D passenger lymphocytes: case report and literature review.

The passenger lymphocyte syndrome (PLS), often associated with immune-mediated hemolytic anemia after solid organ and hematopoietic stem cell transplantation, is the result of concomitant transplantation of donor lymphocytes along with the donor allograft. Antibodies directed against recipient red blood cells (RBCs) are frequently found in ABO-mismatched solid organ transplants; however, passenger lymphocyte-mediated hemolysis due to Rh-incompatible antibodies has only rarely been reported. In this report, we present a case of severe hemolytic anemia related to the PLS in an ABO-matched renal allograft recipient. The recipient's blood type was A Rh(D) positive; and the donor, who had been previously alloimmunized, was A Rh(D) negative. The renal allograft recipient's hemoglobin abruptly decreased on postoperative day 12 in the setting of a newly positive direct antiglobulin test and anti-D antibodies in the plasma. The patient required intermittent RBC transfusions for ongoing hemolysis during the first 6 months post-renal transplant. Of all reported cases of anti-D-mediated PLS, our patient would seem to have been one of the most severe, as indicated by a nadir hemoglobin of 41 g/L and the need for 23 U of transfused RBCs. A hemolytic anemia occurring after organ transplantation should raise the possibility of donor-derived antibodies directed against the recipient RBCs. Passenger lymphocyte syndrome-associated hemolysis is occasionally severe as in our case, but can be effectively treated with compatible RBC transfusions.