Acquired Amegakaryocytic Thrombocytopenia Research Articles

Case report:Clinical manifestations and therapeutic options following rhTPO-induced neutralizing antibody production in a child with immune thrombocytopenia.

Recombinant human thrombopoietin (rhTPO) is commonly used to improve low platelet status in immune thrombocytopenia (ITP), as one protein product, even with a very low rate, there is still the possibility to produce neutralizing antibodies of thrombopoietin (TPO). We described a 7-year-old boy with ITP and normal TPO levels who had previously received rhTPO for 2 weeks but showed persistent thrombocytopenia and was misdiagnosed as acquired amegakaryocytic thrombocytopenia (AATP) and ineffectively treated with cyclosporine A (CsA) in combination with avatrombopag (AVA). As suspicious the TPO neutralizing antibody development as re-test of TPO level is 0, the CD20 + deletion antibody drug rituximab (RTX) was prescribed and received efficacy. rhTPO serves as one bio-protein drug and should be cautious with developing neutralizing antibodies if the drug effect is lost. The tests for antibody and/or TPO level should be done for the diagnosis, and the antibody eradication medication as an anti-CD20 antibody, RTX, should be prescribed to delete thes e neutralizing antibodies to recover the TPO level to reattain the response of ITP treatment.

Acquired Amegakaryocytic Thrombocytopenia with Glycoprotein IIb/IIIa Antibody in a Patient with Mantle Cell Lymphoma.

Background Acquired amegakaryocytic thrombocytopenia (AAMT) is a rare disorder characterized by thrombocytopenia, marked megakaryocytic hypoplasia, and preserved other-lineage hematopoiesis in the bone marrow. The etiology of AAMT remains poorly understood owing to its rarity. Case description We encountered a diagnostically challenging case involving a 66-year-old man who showed severe thrombocytopenic bleeding with isolated megakaryocytic hypoplasia, elevated serum thrombopoietin levels, glycoprotein IIb/IIIa antibody positivity, and prolonged platelet transfusion refractoriness following mantle cell lymphoma (MCL). Treatment with corticosteroids and intravenous immunoglobulin was ineffective, while a combination of multiagent chemotherapy, including rituximab, was beneficial for both thrombocytopenia and MCL. Ultimately, the patient was diagnosed with AMMT and immune thrombocytopenia (ITP)-like platelet destruction. Discussion This case suggests that AAMT and ITP are non-exclusive and sometimes overlap as components of a broad spectrum of platelet-related autoimmune diseases.

The Development of Acquired Amegakaryocytic Thrombocytopenia in a Patient with Idiopathic Thrombocytopenic Purpura

A 67-year-old Japanese male patient with Helicobacter pylori infection developed severe thrombocytopenia and was diagnosed with primary immune thrombocytopenia (ITP) on December 22, 2021. He was treated with Helicobacter pylori eradication therapy, corticosteroids, and eltrombopag (ELT). The platelet count (PLT) improved rapidly; however, after ELT cancellation and corticosteroid reduction, the PLT swiftly decreased. When the corticosteroid dose was increased, the PLT rapidly increased. The corticosteroid dose was reduced immediately; however, the patient presented with subacute arterial obstruction in the right leg and ultimately underwent surgical thrombectomy and transmetatarsal amputation. After corticosteroid cancellation, the PLT again decreased swiftly. Corticosteroids and ELT were thus re-administered. The PLT showed a tendency to recover temporarily, although the drug reaction was not gradual and showed a tendency to decrease. After a repeated BM aspiration, only megakaryocytes were not detected. We determined that the pathogenesis of the severe thrombocytopenia converted from ITP to acquired amegakaryocytic thrombocytopenia (AAMT). Cases of a conversion from ITP to AAMT are extremely rare, and the mechanism underlying this conversion is not well understood. Herein, we report the first case, to the best of our knowledge, in which transmetatarsal amputation triggered the progression of ITP to AAMT.

Acquired Amegakaryocytic Thrombocytopenia Progressing to Aplastic Anaemia.

Acquired amegakaryocytic thrombocytopenia (AAMT) is a rare disorder of the bone marrow characterized by a lack of megakaryocytes and preservation of other cell lines. It can occur due to an intrinsic stem cell defect or secondary to viral infections, autoimmune disorders, lymphoproliferative disorders or environmental toxins. With time, it can progress to aplastic anaemia (AA) and can have a poor prognosis. No standard guidelines exist for the treatment of AAMT progressing to AA. Herein, we report a rare case of AAMT leading to AA and review the handful of cases previously published in the literature.LEARNING POINTSAcquired amegakaryocytic thrombocytopenia can present as isolated severe thrombocytopenia which can initially be misdiagnosed as immune thrombocytopenia.Lack of response to steroids and intravenous immunoglobulin should raise suspicion for acquired amegakaryocytic thrombocytopenia.Over time, acquired amegakaryocytic thrombocytopenia can progress to aplastic anaemia, which confers a worse prognosis.

Pembrolizumab-Induced Acquired Amegakaryocytic Thrombocytopenia and Successful Combination Treatment With Eltrombopag, Romiplostim and Cyclosporine: A Brief Communication.

Pembrolizumab is a humanized antibody directed against the programmed death-1 receptor on the cell surface, resulting in a T-cell-mediated immune response against tumor cells that can be complicated by immune-related adverse events. Here we present a novel case of pembrolizumab-induced acquired amegakaryocytic thrombocytopenia (AAT) in a patient with metastatic nasopharyngeal carcinoma. AAT is an incredibly rare and challenging entity for which there is no standardized treatment. We discuss our therapeutic approach using a calcineurin inhibitor and thrombopoietin receptor agonists for successful treatment of AAT and resumption of multiagent cytotoxic chemotherapy.

Successful Treatment of Acquired Amegakaryocytic Thrombocytopenia (AAT) with Cyclosporine and Eltrombopag: A Case Report

Successful Treatment of Acquired Amegakaryocytic Thrombocytopenia (AAT) with Cyclosporine and Eltrombopag: A Case Report

Invasive Thymoma with Pure Red Cell Aplasia and Amegakaryocytic Thrombocytopenia

We here describe a case involving a 67-yearold female patient who was referred to our hospital due to severe anemia (hemoglobin, 5.0 g/dL), thrombocytopenia (platelet count, 0.6 × 104/μL), and a mediastinal shadow with calcification noted on X-ray. On admission, an anterior mediastinal tumor was detected, and bone marrow biopsy revealed few megakaryocytes and severely reduced numbers of erythroid cells. The diagnosis was thymoma with pure red cell aplasia (PRCA) and acquired amegakaryocytic thrombocytopenia (AAMT). On Day 8 of admission, the patient received immunosuppressive therapy together with cyclosporine for the 2 severe hematologic diseases, which were stabilized within 2 months. Subsequently, total thymectomy was performed. The diagnosis of the tumor invading the left lung was invasive thymoma, Masaokakoga stage III. The histological diagnosis was World Health Organization type AB. Thymoma accompanied with PRCA and AAMT is very rare, and, based on our case, immunotherapeutic therapy for the hematologic disorders should precede surgical intervention.

P247 Common variable immunodeficiency (CVID) with acquired amegakaryocytic thrombocytopenia (AAT) and kikuchi-fujimoto disease (KFD)

AAT and KFD are uncommon entities not associated with CVID.

Acquired Amegakaryocytic Thrombocytopenia in a Child: A Very Rare Case

Acquired amegakaryocytic thrombocytopenia (AATP) is a very rare hematological disorder causing severe thrombocytopenia and bleeding. Our patient a two year old girl presented with history of severe bleeding from nose, gums, conjunctive with purpuric and petechial spots all over the body. She had mild hepatosplenomegaly with very low Platelet counts. Bone marrow examination revealed absence of apparent megakaryocytes. Bone marrow biopsy ruled out disorders of marrow suppression. This child was treated with methyl prednisolone, prednisolone and oral cyclosporine for 5 months. On follow up the child has been asymptomatic with complete improvement of the platelet counts and recovery of bone marrow picture.

“Almost Bleeding to Death”: The Conundrum of Acquired Amegakaryocytic Thrombocytopenia

Acquired amegakaryocytic thrombocytopenia (AAT) is a rare hematological disorder causing severe thrombocytopenia and bleeding. Previous in vitro studies postulated both cell-mediated suppression of megakaryocytopoiesis in early megakaryocytic progenitor cells and humoral-mediated suppression by anti-thrombopoietin antibodies as possible etiologies of AAT. Patients with AAT usually present with severe bleeding and thrombocytopenia that is unresponsive to steroids and intravenous immunoglobulin (IVIG). Although standard guidelines have not been established for management of AAT, a few case reports have indicated a response to immunosuppressive treatment. The prompt recognition of this disease entity is essential in view of the substantial risk of morbidity and mortality from excessive bleeding. We report a case of AAT successfully treated with equine antithymocyte globulin (ATG) and cyclosporine (CSP).

Acquired Amegakaryocytic Thrombocytopenia in a Patient With Occupational Chemical Exposure

Acquired amegakaryocytic thrombocytopenia (AAT) is a hematologic disorder that presents as thrombocytopenia with absent megakaryocytes in the bone marrow. Causes of AAT include toxins, drugs, viral infections, systemic lupus erythematosus, and cytokine deficiencies. Patients with AAT should be followed for possible progression to aplastic anemia or myelodysplastic syndrome. We present a case of a 61-year-old woman with AAT due to occupational chemical exposure.

Successful treatment of acquired amegakaryocytic thrombocytopenia with cyclosporine in adult onset Still’s disease

Acquired amegakaryocytic thrombocytopenia (AAT) is a rare disorder, characterized by severe thrombocytopenia and selective, marked decrease or absence of megakaryocytes in the bone marrow. We describe a 29-year-old female with adult onset Still's disease preceding a diagnosis of AAT and autoimmune hemolytic anemia, which was successfully treated with cyclosporine. This is the first case of AAT in a patient with adult onset Still's disease.

Acquired amegakaryocytic thrombocytopenia: Three case reports and a literature review

Acquired amegakaryocytic thrombocytopenia (AAT) is a rare disease characterized by thrombocytopenia due to selective reduction/absence of bone marrow (BM) megakaryocytes. In the BM culture isolated reduction of colony-forming units-megakaryocyte (CFU-Mk) may occur. BM aspirates and trephine biopsies were obtained from all patients and processed by routine methods. In vitro BM culture and cytogenetic analysis was performed in one patient. This article presents three patients with manifested signs of hemorrhagic syndrome due to severe thrombocytopenia caused by an absence/significant reduction of BM megakaryocytes. Existence of systemic or any other disease was excluded in all patients. BM culture of the second patient showed reduction of all hematopoietic progenitors. In the subsequent course of the disease in this patient, signs of dysplastic erythrocytic series and megakaryocytes were also noted, although there were no positive proofs of evolution into myelodysplastic syndrome. AAT is a disease of hematopoietic stem cells manifesting in a certain period as amegakaryocytic thrombocytopenia which subsequently may progress into aplastic anemia or myelodysplastic syndrome. Patients were treated with corticosteroids, lithium carbonate, androgens, vincristine, immunoglobulins, folic acid, platelet and erythrocyte transfusions along with plasma substitution. The first patient reacted positively to the therapy. In two other patients a minimal, short-term therapeutic effect was achieved, followed by improvement of hemorrhagic syndrome and an insignificant increase in platelet count. In one patient the treatment was stopped after 4 months and the other died of bleeding after 4 months. AAT is a rare disease with unpredictable course. This is a case report of three patients with AAT and different therapeutic effects.