Warm red blood cell autoantibodies and clinical diagnoses in patients with or without autoimmune hemolysis.

OBJECTIVES: Red blood cell autoantibodies (RBC autoAbs) of IgG class are found in the majority of patients with warm autoimmune hemolytic anemia (wAIHA) but sometimes also during the pretransfusion testing of patients with different diagnoses but without hemolysis. The aim of the study was to identify the main differences between these two groups of patients according to age, gender, subclass and titer of IgG RBC autoAbs and diagnosis. MATERIAL AND METHODS: In the 9-year retrospective study, data were collected from records of 291 patients with IgG RBC autoAbs detected by gel technique, from which 111 with wAIHA. RESULTS: More than 85% of patients in both groups were over 40 years old, with male to female ratio 1:1.9 in wAIHA vs 1:1.3 in patients without hemolysis (P=0.0916). The main characteristics of patients with wAIHA vs patients without hemolysis were: IgG only 38% vs 70%, IgG+Complement 62% vs 30%, total IgG1 79% vs 55%, IgG1+IgG3 35% vs 11%, titer of 100 for IgG1+IgG3 17% vs 3% (P<0.0001), respectively, while titer of 100 for IgG1 18% vs 9% (P=0.0241). The underlying diagnosis in wAIHA vs patients without hemolysis: hematologic disorders 41% vs 22% (P=0.0006), autoimmune disorders 12% vs 13% (P=0.8033), solid tumors 5% vs 14% (P=0.0154) and surgery procedures 6% vs 26% (P<0.0001). CONCLUSION: We observed more wAIHA patients with high titer of IgG1 and high prevalence of IgG1+IgG3 and consider that patients without hemolysis having identical results might be interesting to find out how they are protected from damage by RBC autoAbs.

Do patients with autoantibodies or clinically insignificant alloantibodies require an indirect antiglobulin test crossmatch?

BACKGROUND: Compatibility testing is the standard protocol that identifies suitable blood for patients requiring transfusion. If the antibody screen is negative or no clinically significant antibodies are detected, BCSH guidelines and AABB standards allow an immediate-spin crossmatch (IS XM) or even electronic issue. The testing requirement is less clear where autoantibodies or non-clinically significant alloantibodies compromise the indirect antiglobulin test crossmatch (IAT XM). Performing an IAT XM will give a mismatched result anyway, delays the supply of blood to the patient, and provides no additional benefit or safety. STUDY DESIGN AND METHODS: From January 2002 to April 2006, the provision of blood for autoimmune hemolytic anemia (AIHA) patients with autoantibodies and no alloantibodies as well as patients with alloantibodies that exhibited a "high-titer, low-avidity" (HTLA) mode of reactivity was reviewed. RESULTS: A total of 222 AIHA patients (428 samples) with autoantibodies had 1585 units of red cells supplied after IAT XM; 1308 (82.5%) were mismatched. In 50 patients (80 samples) with HTLA-like antibodies, 286 units of 328 (87.2%) were mismatched by IAT XM. CONCLUSION: No adverse reactions were reported for the study groups where "suitable" blood was provided after a serologically mismatched IAT XM. No additional benefit for these patients can be claimed by performing an IAT XM over an IS XM, as a check of ABO match. The IAT XM is both costly and time-consuming. It is proposed that for these study group patients, a reduction to an IS XM can be applied and can be beneficial.

Anaemia in systemic lupus erythematosus: from pathophysiology to clinical assessment.

Haematological abnormalities are common in systemic lupus erythematosus. Anaemia is found in about 50% of patients, with anaemia of chronic disease being the most common form. Impaired erythropoietin response and presence of antibodies against erythropoietin may contribute to the pathogenesis of this type of anaemia. Patients with autoimmune haemolytic anaemia usually belong to a distinct category, which is associated with anticardiolipin antibodies, thrombosis, thrombocytopenia, and renal disease, often in the context of secondary antiphospholipid syndrome. Autoantibodies, T lymphocytes, and deregulation of the cytokine network can affect bone marrow erythropoiesis, leading to anaemia.

Assessment of lipid peroxidation and serum vitamin E concentration in dogs with immune-mediated hemolytic anemia.

OBJECTIVE: To determine plasma malondialdehyde (MDA) and serum vitamin E concentrations in dogs with immune-mediated hemolytic anemia (IMHA) and healthy control dogs. SAMPLE POPULATION: Serum and plasma samples from 36 dogs with IMHA and 40 healthy control dogs. PROCEDURE: Blood samples were collected from all study dogs. Plasma MDA concentrations were measured by use of a commercial colorimetric assay, and serum vitamin E concentrations (alpha-, gamma, and delta-tocopherol concentrations) were measured via high-performance liquid chromatography. RESULTS: Plasma MDA concentrations were significantly higher in the dogs with IMHA than in the control dogs. Compared with control dogs, serum alpha-, gamma-, and &tocopherol concentrations were significantly lower in the IMHA-affected dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated a state of oxidative stress and reduced antioxidant reserve in dogs with IMHA; this finding provides support for further investigation of the potential benefits of antioxidant treatment in dogs with this disease.

Assessment of red cell autoantibodies in autoimmune hemolytic anemia of warm type by a radioactive anti-IgG test.

To evaluate the applicability of a radioactive 125I-anti-IgG test (RIAT) for the detection of small amounts of IgG antibodies on red blood cells (RBC) of patients with autoimmune hemolytic anemia of warm type (AIHA), RBC of 125 patients were studied (AIHA, n = 53; Coombs'-negative AIHA, n = 6; chronic cold agglutinin disease, n = 7; non-immune anemias, n = 59). It was found that the RBC of all cases (33/33) with a positive direct IgG antiglobulin test (DAT-IgG), but also 13 out of 20 patients with a negative DAT-IgG, but detectable complement (C3/C4), and 4 out of 6 cases with Coombs'-negative AIHA gave positive results in the direct RIAT. RBC-associated IgG was higher in the DAT-IgG positive group (n = 33; -x = 8.1%) than in the DAT-IgG negative group (n = 26; -x3.4%). There was no correlation between hypergammaglobulinemia and RBC-associated IgG. The sensitivity of the indirect RIAT was not remarkable better as compared to the indirect antiglobulin test. The RIAT is valuable in the serology of borderline cases of AIHA.