INTRODUCTION:

: Thrombotic microangiopathy (TMA) is characterized by microvascular thrombosis, thrombocytopenia, and microangiopathic hemolytic anemia. Previous studies have shown that cyclosporine (CsA) is associated with TMA but the number of reported cases is very limited. We describe a 13-year-old girl with CsA-associated TMA and thrombocytopenia-associated multiple organ failure (TAMOF).

CASE REPORT:

: The patient was diagnosed with polyglandular deficiency syndrome and had a history of celiac disease, autoimmune thyroiditis, and diabetes mellitus type I. CsA was started 7 months before her admission to our pediatric intensive care unit for persistent diarrhea associated with celiac disease. At the time of her admission to our pediatric intensive care unit, she was thrombocytopenic and anemic with multiple organ failure. Laboratory and clinical findings were consistent with TMA and TAMOF. CsA was discontinued and therapeutic plasma exchange was performed daily for 5 days. The patient improved clinically, laboratory findings normalized, and TMA and multiple organ failure dissolved.

CONCLUSION:

: This case report indicates that therapeutic plasma exchange may be effective in the treatment of CsA-associated TMA and TAMOF, especially in the presence of systemic findings.

CD3 chain expression defects including CD3 gamma, epsilon, delta, and zeta chain subunits, are autosomal recessive inherited severe combined immunodeficiencies (SCID). The phenotype is usually T-B+NK+ SCID with lymphopenia where the clinical findings may be mild (CD3γ) or severe (CD3δ, ε, ζ) owing to the underlying molecular defect. There is limited information about the disease in literature.Here, we present two siblings from non-consanguineous family with autoimmunity including Evans syndrome, autoimmune hepatitis, nephrotic syndrome, and Hashimoto's thyroiditis and with no previous history of infections. To define the molecular basis of the disease, we performed linkage analysis around the CD3 receptor cluster and found consistent linkage to this region.The patient one displayed low TCRαβ expression, low IgG, low IgA, low IgM, low CD3, low CD4, low CD8. The patient two also displayed low TCRαβ expression and low anti-HBs titer. We went onto identify a homozygous splicing mutation (IVS2-1G>C) in the two affected individuals in the CD3γ gene.To date, only four cases have been reported with CD3γ deficiency. Occasionally, the patients present with only autoimmunity including autoimmune hemolytic anemia, vitiligo, Hashimoto's thyroiditis, and autoimmune enteropathy. However, Evans syndrome, autoimmune hepatitis, and nephrotic syndrome have not been reported in previous cases. We believe that our cases will contribute to the literature.

A 9-month-old boy with life-threatening multiresistant pure red cell anemia/autoimmune hemolytic anemia within the frame of a possible, undiagnosed immune-mediated disease was initially treated with prednisone. Further-line therapies of the following 7 relapses included immunoglobulins, rituximab, cyclophosphamide, and alentuzumab followed by other maintenance treatments as cyclosporine, methotrexate, and mycophenolate. After all the administered therapies failed, the patient was successfully treated by splenectomy followed by fludarabine and then sirolimus as maintenance treatment. Relapses might have been caused by the lack of a complete debulking of triggering cells and/or ineffective maintenance therapy. Splenectomy and sirolimus may have played a complementary role in the management of both situations.

Immune hemolytic anemia is a well-recognized complication after allogeneic hematopoietic stem cell transplantation (HSCT). There are 4 possible causes for this complication. First, antibodies present in the recipient destroy donor cells. Second, donor red cell antibodies at the time of stem cell infusion are transferred to the recipient. Third, sometimes, engrafted donor lymphocytes cause active production of red cell antibodies. Fourth, another cause of hemolysis after allogeneic HSCT is autoimmune hemolytic anemia (AIHA). It is thought to be due to antibodies produced by the donor's immune system against antigens on red cells of donor origin. Autoimmune hemolytic anemia after allogeneic HSCT is rare, it is still not well characterized, and it represents a life-threatening situation. We describe 2 patients with acute myeloid leukemia treated with intensive chemotherapy and umbilical cord blood stem cell transplantation (UCBT). One patient developed AIHA at day +182 and the other at day +212 after receiving UCBT. Patients received 5 and 7 line treatment options, respectively, including continuous corticosteroids, intravenous immunoglobulin, splenectomy, cyclophosphamide, plasma exchange, rituximab, bortezomib, and eculizumab. However, both patients died because of massive hemolysis after 85 and 106 days of intensive treatment, respectively. These cases reflect the extreme difficulty in the therapeutic management of patients with AIHA following UCBT. After an extensive review of the literature, the exact physiopathologic mechanisms of AIHA after allogeneic HSCT in general, and after UCBT in particular, and therefore an effective treatment remain unknown.

A 68-year-old man was diagnosed with chronic lymphocytic leukemia (CLL) 3 years ago. His course was progressive, and he was complicated with autoimmune hemolytic anemia (AIHA). After the lack of efficacy of prednisone and cyclo-phosphamide, rituximab (375mg/m(2)) was administered based on the presence of CD20 positive leukemic cells by flow cytometric analysis of bone marrow. During 4 courses of rituximab administration, both anemia and hemolysis improved dramatically. Furthermore, the percentage of CLL cells in his peripheral blood was reduced. Rituximab may be one of the effective treatments for CLL associated AIHA in Japan as well as in foreign countries.

Previously, we described a group of patients with hemocytopenia who did not conform to diagnostic criteria of known hematological and nonhematological diseases. Most patients responded well to adrenocortical hormone and/or high-dose intravenous immunoglobulin treatment, indicating that cytopenia might be mediated by autoantibodies. Autoantibodies were detected on the membrane of various bone marrow (BM) hemopoietic cells by bone marrow mononuclear-cell-Coombs test or flow cytometric analysis. Thus, the hemocytopenia was termed "Immunorelated Pancytopenia" (IRP) to distinguish it from other pancytopenias. Autoantigens in IRP were investigated by membrane protein extraction from BM hemopoietic cells and BM supernatant from IRP patients. Autoantibody IgG was detected in the BM supernatant of 75% of patients (15/20), which was significantly higher than that in aplastic anemia, myelodysplastic syndrome, or autoimmune hemolytic anemia patients (0%) and normal healthy controls (0%) (P < 0.01). Autoantigens had approximate molecular weights of 25, 30, 47.5, 60, 65, 70, and 80 kDa, some of which were further identified by mass fingerprinting. This study identified that a G-protein-coupled receptor 156 variant and chain P, a crystal structure of the cytoplasmic domain of human erythrocyte band-3 protein, were autoantigens in IRP. Further studies are needed to confirm the antigenicity of these autoantigens.

Autoantibodies against integral membrane proteins are usually pathogenic. Although anti-endothelial cell antibodies (AECAs) are considered to be critical, especially for vascular lesions in collagen diseases, most molecules identified as autoantigens for AECAs are localized within the cell and not expressed on the cell surface. For identification of autoantigens, proteomics and expression library analyses have been performed for many years with some success. To specifically target cell-surface molecules in identification of autoantigens, we constructed a serological identification system for autoantigens using a retroviral vector and flow cytometry (SARF). Here, we present an overview of recent research in AECAs and their target molecules and discuss the principle and the application of SARF. Using SARF, we successfully identified three different membrane proteins: fibronectin leucine-rich transmembrane protein 2 (FLRT2) from patients with systemic lupus erythematosus (SLE), intercellular adhesion molecule 1 (ICAM-1) from a patient with rheumatoid arthritis, and Pk (Gb3/CD77) from an SLE patient with hemolytic anemia, as targets for AECAs. SARF is useful for specific identification of autoantigens expressed on the cell surface, and identification of such interactions of the cell-surface autoantigens and pathogenic autoantibodies may enable the development of more specific intervention strategies in autoimmune diseases.

A 58-year-old woman presented with rheumatoid arthritis-associated Evans syndrome (simultaneous autoimmune hemolytic anemia and autoimmune thrombocytopenic purpura); she was treated unsuccesfully with steroids, romiplostin, rituximab, immunoglobulin G, and splenectomy. The platelet count responded to the combined use of prednisone, eltrombopag, and romiplostin. It may be more reasonable to use combined treatments than sequential monotherapies.

Chronic lymphocytic leukemia (CLL) is frequently associated with autoimmune hemolytic anemia (AIHA). However, the mechanisms governing the association between CLL and AIHA are poorly understood. MicroRNAs (miRNAs) have been associated with different clinico-biological forms of CLL and are also known to play a substantial role in autoimmunity. However, there are no studies correlating miRNA expression with the likelihood that patients with CLL will develop AIHA. In this study, we found that malignant B-cells from patients with CLL subsequently developing AIHA present nine down-regulated (i.e. miR-19a, miR-20a, miR-29c, miR-146b-5p, miR-186, miR-223, miR-324-3p, miR-484 and miR-660) miRNAs. Interestingly, two of these miRNAs (i.e. miR-20a and miR-146b-5p) are involved in autoimmune phenomena, and one (i.e. miR-146b-5p) in both autoimmunity and CLL. Furthermore, we demonstrated that miR-146b-5p modulates CD80, a molecule associated with the B-T-cell synapse and in restoration of the antigen presenting cell capacity of CLL cells.