Acquired Pure Red Cell Aplasia and Acquired Amegakaryocytic Thrombocytopenia Associated With Clonal Expansion of T-Cell Large Granular Lymphocytes in a Patient With Lipopolysaccharide-responsive Beige-like Anchor (LRBA) Protein Deficiency.

Acquired pure red cell aplasia and acquired amegakaryocytic thrombocytopenic purpura are rare in children. Similarly, clonal expansion of T-cell large granular lymphocytes is infrequently seen in pediatrics. Lipopolysaccharide-responsive beige-like anchor (LRBA) protein deficiency is a recently described immunodeficiency syndrome that has been associated with inflammatory bowel disease and autoimmune phenomena such as Evans syndrome. Here, we describe a patient with LRBA deficiency who developed acquired pure red cell aplasia and acquired amegakaryocytic thrombocytopenic purpura associated with expansion of clonal T-cell large granular lymphocytes. This has not been described in the literature previously and adds to the knowledge on the spectrum of manifestations of LRBA deficiency.

Amegakaryocytic Thrombocytopenia and Subsequent Aplastic Anemia Associated with Apparent Epstein-Barr Virus Infection.

Acquired amegakaryocytic thrombocytopenia (AAT), a rare entity characterized by severe thrombocytopenia and the absence of megakaryocytes in the bone marrow, may mimic or precede the diagnosis of aplastic anemia (AA). Here, we describe a patient who presented with apparent Epstein-Barr virus (EBV)-associated immune thrombocytopenia resistant to several lines of therapies, which was in fact a form of AAT with some features of AA. He eventually responded to therapy with eltrombopag, cyclosporine A (CSA), and antithymocyte globulin (ATG) and recovered completely. EBV infection is known to cause a variety of benign and malignant hematologic disorders, including bone marrow failure. However, to the best of our knowledge, this is the first case report of EBV-associated AAT. Treatment options for AAT are still not well defined, and even response to eltrombopag together with CSA and ATG does not always imply successful therapy. The natural history of EBV infection may well be sufficient to explain unexpected eventual recovery.

Nonclinical Safety Profile of BMS-986001, a Nucleoside Transcriptase Inhibitor for Combination Retroviral Therapy.

Nucleoside reverse transcriptase inhibitors (NRTIs)/nucleotide reverse transcriptase inhibitors are key components of combination antiretroviral therapy for HIV infection. First-generation NRTIs are associated with mitochondrial toxicity in patients, mainly due to inhibition of human DNA polymerase γ (hDNA polγ) that manifests as adverse events such as lipodystrophy, lactic acidosis, myopathy, cardiomyopathy, or nephropathy in patients. In chronic nonclinical studies in rodents and nonrodents, eukaryotic (host) mitochondrial toxicity manifests as some drug-specific toxicities similar to human toxicity. BMS-986001, a novel thymidine analog with minimal hDNA polγ inhibition, has demonstrated antiretroviral activity in early clinical studies. The primary toxicity of BMS-986001 in rats and monkeys is bone marrow dyserythropoiesis with associated decreases in red blood cell mass. Additionally, at high doses, severe platelet reductions accompanied by cutaneous petechiae began during weeks 8 and 11 in 3 of 60 monkeys in chronic toxicity studies. In a 6-month study, platelet reductions required euthanasia of the 2 affected monkeys (300 mg/kg/d) at week 14, but with dose reduction (200 mg/kg/d) remaining monkeys had no platelet changes. One affected monkey (200 mg/kg/d) in a 9-month study completed dosing and its platelet counts recovered during a 1-month recovery. Formation of platelet-bound immunoglobulin in the presence of BMS-986001, together with rapid and complete platelet recovery in the absence of BMS-986001, suggested that platelet decreases in monkeys may be immune mediated. No findings indicative of mitochondrial toxicity were observed in rats or monkeys given BMS-986001, suggesting an improved safety profile compared to marketed NRTI or tenofovir disoproxil fumarate.

Laboratory testing for platelet antibodies.

Laboratory testing for immune-mediated thrombocytopenias involves identification and classification of antibodies present in patient sera or attached to patient platelets. This article summarizes the available types of platelet antibody testing and applications in disorders such as neonatal alloimmune thrombocytopenia, post-transfusion purpura, multiple platelet transfusion refractoriness, immune thrombocytopenia, and drug-induced thrombocytopenia.

Managing uncontrolled postsplenectomy reactive thrombocytosis in idiopathic thrombocytopenic purpura: role of thrombocytapheresis.

Reactive thrombocytosis occurs in response to infection, trauma, or surgery. Splenectomy alone accounts for 19% of all possible causes of extreme thrombocytosis. We performed thrombocytapheresis in a young lady with chronic idiopathic thrombocytopenic purpura (ITP) who developed postsplenectomy reactive thrombocytosis. Her post splenectomy platelet count was 227 × 10(6)/ml which elevated to 1623 × 10(6)/ml on the 7th postoperative day. A single thrombocytapheresis procedure reduced her platelet to 403 × 10(6)/ml. She was discharged on the 10th postoperative day and then maintained a count of 204-238 × 10(6)/ml with aspirin. Thrombocytapheresis reduces the platelet count rapidly in thrombocytosis and prevents patients from having thrombotic events. However, such procedures should be performed very meticulously to ensure patient safety.

Bilateral nephrectomy for the treatment of refractory lupus nephritis with features overlapping with thrombotic microangiopathy resembling thrombotic thrombocytopenia purpura.

We report a patient with a diagnosis of systemic lupus erythematosus who concurrently developed a syndrome of thrombotic microangiopathy that resembled thrombotic thrombocytopenic purpura. The patient underwent plasma exchange and immunosuppressive therapy for months before clinical improvement was finally achieved through bilateral nephrectomy. Ultimately, our patient died of disseminated aspergillosis from prolonged immunosuppression. We believe that recognition of bilateral nephrectomy as a potential treatment earlier in her course would have spared her this unfortunate demise. We hope that this review of current literature will help the reader to consider bilateral nephrectomy in patients with refractory systemic lupus erythematosus with clinical overlap of thrombotic microangiopathy resembling thrombotic thrombocytopenic purpura.

Mycophenolate mofetil therapy for juvenile dermatomyositis with immune thrombocytopenic purpura.

A 6-year-old girl, who had received corticosteroid and cyclosporine on the diagnosis of interstitial pneumonitis related to juvenile dermatomyositis, developed severe thrombocytopenia. Her thrombocytopenia was resistant to repeated intravenous immunoglobulin administration and methylprednisolone pulse therapy. After additional treatment with mycophenolate mofetil (MMF), instead of cyclosporine, the thrombocytopenia improved, facilitating a reduction in the dose of corticosteroid without exacerbation of the interstitial pneumonitis. We propose MMF as effective option in the treatment of immune thrombocytopenic purpura with autoimmune disease.

[Dynamic beta-endorphin determination in hematologic patients].

AIM: To perform a dynamic study of beta-endorphin, hypoxia-inducible factor-1alpha (HIF-1alpha), and cytokines in hematologic patients. SUBJECTS AND METHODS: Fifty-nine patients with different types of acute leukemia (AL), 30 with anaplastic anemia (AA), 24 with thrombocytopenic purpura, and 20 healthy volunteers were examined during their 40-day stay at 3200 m above sea level. beta-Endorphin and HIF-la were measured by a sandwich-type enzyme immunoassay using the Abcam antibodies. Cytokines (interleukin (IL)-2, IL-6, and tumor necrosis factor-alpha) were estimated by enzyme immunoassay applying the Pro Con kits (Saint Petersburg). RESULTS: Serum beta-endorphin concentrations were 1.5-2-fold above the normal values in the majority of patients with AL. The patients with initial leukocytosis at onset of disease were noted to have elevated white blood cell beta-endorphin concentrations up to 85.9 +/- 22.4 pg/ml; moreover, during chemotherapy this index increased about two times (170.74 +/- 33.8 pg/ml). There was a direct correlation between the concentrations of beta-endorphin and HIF-1alpha (r = 0.9) and an inverse correlation between the levels of IL-6 and beta-endorphin (r = -0.7). On ascending to 3200 m, under the conditions of hypoxic hypoxia the patients with AA or idiopathic thrombocytopenic purpura showed a considerable increase in serum beta-endorphin concentrations, mainly in the acute period of being at high altitudes. CONCLUSION: Stress factors (tumor, use of cytostatics, pain, anemia, hypoxia, high environment temperature) stimulate the elaboration of beta-endorphin, particularly in the white blood cells of patients with AL during chemotherapy. The highest elevation in the index was seen during acute adaptation to hypoxic hypoxia.

Thrombotic microangiopathies: new insights and new challenges.

PURPOSE OF REVIEW: Thrombotic microangiopathies (TMAs) manifest as a spectrum of related disorders in the form of thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). New data on both diseases support more and more the relatedness of the disorders and reveal related pathomechanisms, which, however, manifest in different organs. TTP develops primarily at neurological sites, and also in the kidney, and HUS is a kidney disease. In TTP thrombi formation occurs subsequently to the release of multimers of von Willebrand factor (vWF), and in HUS endothelial cell damage is considered the reason for complement and platelet activation leading to thrombus formation. RECENT FINDINGS: Genetic mutations are associated with both disorders: in TTP the ADAMTS13 gene, the vWF cleaving protease, is affected, and in HUS several complement genes are mutated. In addition autoimmune forms, with acquired, de-novo generated inhibitors in the form of autoantibodies exist for both disorders, affecting ADAMTS13 in TTP or the central complement inhibitor factor H in HUS. In HUS autoantibodies can develop in the context of a specific mostly homozygous chromosomal deletion that represents a new subform of the disease, which is termed DEAP-HUS (deficient for CFHR proteins and autoantibody positive HUS). SUMMARY: As the underlying disease mechanisms of TMA are now being better understood new options for a more precise diagnosis, improved therapy and prognosis for kidney transplantation become available for the benefit of patients. Here we summarize the recent developments in this rapidly progressing field.

Acquired amegakaryocytic thrombocytopenia and red cell aplasia in a patient with thymoma progressing to aplastic anemia successfully treated with allogenic stem cell transplantation.

Association of pure red-cell aplasia with thymoma is well documented. However, acquired amegakaryocytic thrombocytopenia (AAMT) has been rarely associated with thymoma with only five reported cases in literature. We report a patient with thymoma complicated by pure red cell aplasia (PRCA) and AAMT who progressed to develop aplastic anemia (AA). The patient was refractory to 10-months of immunosuppressive therapy with cyclosporine, prednisone, and antithymocyte globulin. She was eventually treated with allogeneic stem cell transplantation (allo-SCT). On Day +323 the patient continues to be transfusion-independent. This case illustrates how in patients with thymoma and AAMT may herald development of AA. This is also the first report of a patient with AAMT progressing to thymoma-associated AA being successfully treated with allo-SCT. The successful outcome suggests allo-SCT as a feasible option similar to other AA patients.

Successful treatment of acquired amegakaryocytic thrombocytopenic purpura refractory to corticosteroids and intravenous immunoglobulin with antithymocyte globulin and cyclosporin.

Four patients with acquired amegakaryocytic thrombocytopenic purpura, who had failed corticosteroids, intravenous immunoglobulin and cyclophosphamide therapy, were treated with antithymocyte globulin, followed by cyclosporin. Three patients achieved complete remission in 28-178 days and the response duration was 16-60 months from the beginning of treatment. One patient achieved a partial response for 2 months followed by myelodysplastic syndrome 5 months later. He died in 9 months due to intracerebral bleeding. Marrow cytogenetics showed 47, XY, +21.

Thrombotic thrombocytopenic purpura associated with multiple myeloma.

Thrombotic thrombocytopenic purpura is a thrombotic microangiopathic disease. Associations with collagen vascular diseases, pregnancy, some drugs, surgical intervention, and infections are documented (known). Malignancy is also one of the known factors associated with thrombotic thrombocytopenic purpura. These malignancies are usually the disseminated solid organ tumors. Hematological malignancies constitute a rare association. Here, we present a patient with thrombotic thrombocytopenic purpura associated with multiple myeloma and discuss the pathogenesis. To our knowledge, this is the first case report of thrombotic thrombocytopenic purpura associated with multiple myeloma.

Glomeruloid hemangioma.

A 64-year-old Japanese woman suffering from idiopathic thrombocytopenic purpura was treated with prednisolone. During the course of steroid withdrawal she developed parotid gland enlargement and cervical lymph node swelling with multiple dome-shaped red papules on her trunk and upper limbs. On admission the patient was found to have numbness of her lower limbs (polyneuropathy), lymph node swelling (organomegaly), high glucose level (endocrinopathy), Bence-Jones protein-kappa in the urine (M protein) and skin with hyperpigmentation, hypertrichosis and multiple glomeruloid hemangiomas (skin abnormalities), indicating polyneuropathy-organomegaly-endocrinopathy-M-protein-skin abnormality (POEMS) syndrome. The patient was also found to have peripheral edema, ascites, and pleural effusion. The glomeruloid hemangiomas had intravascular capillary growth, which was composed of conglomerates of capillaries resulting in structures resembling renal glomeruli. Cells within the capillary loops were lined by endothelial cells with scant cytoplasm (CD31(+)/CD34(+)/CD68(-)/CD105(+)/UEA-1(+)) while the outer surfaces of the loops were covered by either swollen endothelial cells containing PAS- and immunoglobulin-positive eosinophilic hyaline globules (CD31(+)/CD34(-)/CD68(-/+)/CD105(-)/UEA-1(-)) or cells without globules. These two phenotypically different endothelial cells were separated by alpha-smooth muscle actin-positive pericytes. Pericytes and endothelial cells covering the outer surface of the loops were bordered by basement membrane. Biopsy of parotid gland and lymph node indicated Sjögren's syndrome and Castleman's disease of a hyaline-vascular type, respectively. Resumed prednisolone therapy has been successful, and the patient was left with minimal residual symptoms. Glomeruloid hemangioma is a specific marker of POEMS syndrome and is related to Castleman's disease. Idiopathic thrombocytopenic purpura and Sjögren's syndrome may also be related.

Mechanisms of thrombocytopenia in chronic autoimmune thrombocytopenic purpura. Evidence of both impaired platelet production and increased platelet clearance.

Mechanisms of thrombocytopenia were studied in 38 patients with mild to moderately severe chronic autoimmune thrombocytopenia (AITP). 51Cr and 111In-labeled autologous platelet turnover studies and in vitro analysis of committed megakaryocyte progenitors (CFU-Meg) were used as independent measures of platelet production. Autologous 111In-labeled platelet localization studies were performed to assess platelet clearance. Although there was no increase in the frequency of marrow CFU-Meg, a specific increase in the CFU-Meg [3H]TdR suicide rate was seen which was inversely correlated with the platelet count (P less than 0.001). Platelet turnover studies showed significant numbers of patients had inappropriate thrombopoietic responses to their reduced platelet counts. Platelet-associated antibody levels correlated inversely with platelet turnover suggesting that antiplatelet antibody impairs platelet production. The circulating platelet count was best predicted by an index relating platelet production (i.e., turnover) to the spleen-liver platelet clearance that correlated directly with platelet survival (P less than 0.001). In summary, both depressed platelet production and increased platelet clearance by the liver and spleen contribute to the thrombocytopenia of AITP.

Lack of clinical efficacy of rituximab in the treatment of autoimmune neutropenia and pure red cell aplasia: implications for their pathophysiology.

We describe 11 patients with severe refractory autoimmune cytopenias treated with the anti-CD20 monoclonal antibody rituximab. Six patients had autoimmune neutropenia (AIN), two had pure red cell aplasia (PRCA), one had AIN and autoimmune haemolytic anaemia, one had AIN and immune thrombocytopaenia purpura (ITP) and one had PRCA and ITP. Rituximab was administered at a dose of 375 mg/m(2) as an intravenous infusion weekly for 4 weeks. Six of eight patients with AIN and all three patients with PRCA did not respond. Two patients died: one with resistant AIN and autoimmune haemolytic anaemia died of pneumocytis pneumonia infection, and one with PRCA and ITP died of an acute exacerbation of bronchiectasis. Rituximab in AIN and PRCA appears to be less effective than Campath-1H when compared to historical data from our group. This supports the hypothesis that T cells may be important in the pathophysiology of AIN and PRCA.

Tosufloxacin tosilate-induced thrombocytopenic purpura.

Tosufloxacin tosilate, a member of the naphthyridine group, was developed in Japan and became commercially available in 1990. We experienced a 69-year-old male who developed thrombocytopenic purpura due to tosufloxacin tosilate. The diagnosis was made when similar symptoms (petechiae and thrombocytopenia) were induced by inadvertent challenge with tosufloxacin tosilate. In this paper, we report the first case of tosufloxacin tosilate-induced thrombocytopenic purpura and present a brief published work review.

[Acquired amegacaryocytic thrombocytopenic purpura hiding acute myeloid leukemia]. / Un purpura thrombopénique amégacaryocytaire acquis qui cache une leucémie aigue myéloblastique.

Acquired amegakaryocytic thrombocytopenic purpura is a very rare condition characterized by severe thrombocytopenia linked to the reduction or disappearance of megakaryocytes in the bone marrow. It may be primary idiopathic or secondary to many pathological conditions including hematologic disorders. We report the case of a 24-year-old patient admitted for haemorrhagic syndrome caused by immunological thrombocytopenic purpura. The diagnosis was acquired amegakaryocytosis after the failure of corticotherapy and the performance of myelography. The patient was treated with ciclosporin with rapid progression to acute myeloblastic leukemia. The progression of acquired amegakaryocytosis to acute leukemia is reported but it is generally not so rapid and above all it is preceded by myelodysplastic syndrome or medullary aplasia. This study highlights the importance of a close follow-up of these pathologies with a benign-like appearance.