A retrospective analysis of haemolytic reactions to intravenous immunoglobulin using data from the Transfusion-Transmitted Injuries Surveillance System (Ontario).

BACKGROUND AND OBJECTIVES: Haemolysis can occur following intravenous immunoglobulin (IVIG) infusion. Haemovigilance data were analysed using a novel approach for including two control groups with no haemolysis to IVIG. Objectives included a summary of all reactions to IVIG, rate estimates and analysis of haemolytic reactions including risk factors. MATERIALS AND METHODS: Canadian haemovigilance data from Ontario (2013-2021), IVIG distribution and transfusion data from the blood supplier, and data from a large local transfusion registry were used. An 'other-reactions' control group included patients with IVIG reactions that were not haemolytic, and registry patients with no-reaction were the 'no-reaction controls'. Descriptive analysis and two logistic regression models for the different control groups were performed. RESULTS: One thousand one hundred and seventy reactions were included. Most common were febrile non haemolytic (26.1%), minor allergic (24.5%) and IVIG headache (15.3%) followed by haemolytic 10.9% (128/1170). Haemolytic reaction rates decreased over time: rates since 2020 estimated between 1.5 and 2.9/1000 kg IVIG used. The regression model for other-reaction controls identified two risk factors for haemolysis: non-O blood group recipients compared with group O recipients (p value = 0.0106) and IVIG dose per 10 g increase (OR 1.359; 95% CI 1.225-1.506). The model using no-reaction controls gave similar results and also showed no pre-medication was associated with a higher risk of haemolysis (OR 29.084; 95% CI 1.989-425.312). CONCLUSION: The frequency of haemolytic reactions has decreased over time. We confirmed non-O blood group recipients and IVIG dose as risk factors for haemolysis and raise the hypothesis that no pre-medication may increase the risk of haemolysis.

Prevalence of birefringent crystals in cardiac and prostatic tissues, an observational study.

INTRODUCTION: The prevalence of urate crystals in residual tissue samples from coronary arteries, aortic valves and prostate glands was assessed. METHODS: Alcohol-fixed coronary arteries from 55 explanted hearts, alcohol-fixed aortic valves collected from 75 valve replacement surgeries and 40 frozen, unfixed prostate specimens resected during cancer surgery were examined for birefringent crystals with polarising microscopy. RESULTS: In the 55 explanted hearts, 6 (10.9%) contained a coronary artery with birefringent crystals. One of the 75 aortic valves (1.4%) contained negatively and positively birefringent crystals. Nineteen of the 40 (47.5%) prostates contained birefringent crystals. CONCLUSIONS: We found that a remarkable percentage of coronary arteries and prostate specimens contained birefringent crystals. Crystal presence is an obvious prerequisite for possible crystal induced-inflammation in these tissues, just as similar crystals elicit a gouty inflammatory cascade in synovial joints. Further studies are necessary to determine whether urate crystals may play this role in these tissues and, if so, to establish whether urate-lowering therapy may be beneficial in prostatitis and coronary disease.

Development of criteria to distinguish inflammatory from noninflammatory arthritis, enthesitis, dactylitis, and spondylitis: a report from the GRAPPA 2013 Annual Meeting.

OBJECTIVE: To describe a research project to develop simple clinical criteria to aid in the identification of inflammatory arthritis, enthesitis, dactylitis, and spondylitis and distinguish these from non-inflammatory conditions. The criteria are particularly intended to aid non-rheumatologists, e.g., dermatologists, who need assistance identifying psoriatic arthritis in patients with psoriasis, but may be useful to all clinicians in properly diagnosing rheumatologic conditions. METHODS: The proposed research methodology includes the use of a nominal group exercise among expert clinicians and patient focus groups, Delphi exercises among clinicians and patients, application of criteria test sets to a small group of representative patients with inflammatory and non-inflammatory musculoskeletal conditions, and validation by application of optimal criteria sets to large groups of patients with inflammatory and noninflammatory conditions. RESULTS: Examples of elements to describe inflammatory conditions derived from a nominal group exercise conducted at the 2013 GRAPPA annual meeting are described, along with planned project activities. CONCLUSION: This project will lead to the development of practical criteria to aid in the diagnosis and appropriate clinical care of patients with chronic inflammatory musculoskeletal conditions.