Pure red cell aplasia and myasthenia gravis with thymoma: a case report and review of the literature

Pembrolizumab-induced Pure Red Cell Aplasia Successfully Treated with Intravenous Immunoglobulin

We herein report a 64-year-old man who was treated with pembrolizumab for relapsed Hodgkin lymphoma. After the third administration of pembrolizumab, he showed acute anemia with a positive direct anti-globulin test. Because of the markedly erythroid hypoplasia, he was diagnosed with pure red cell aplasia (PRCA) caused by pembrolizumab. He was initially treated with prednisolone, but the reticulocytes decreased after tapering prednisolone. He then received high-dose intravenous immunoglobulin (IVIG) with prednisolone, and PRCA was successfully treated. Although the pathogenesis of PRCA caused by immune checkpoint inhibitors (CPIs) remains unclear, IVIG treatment may be effective for some steroid-refractory CPI-induced PRCA cases.

A systematic review of paraneoplastic syndromes associated with thymoma: Treatment modalities, recurrence, and outcomes in resected cases

OBJECTIVE

Paraneoplastic syndromes associated with thymomas remain incompletely understood. The objective was to examine the association between surgically resected thymomas and paraneoplastic syndromes over the past half century.

METHODS

A primary PubMed/MEDLINE search was used to identify published articles describing paraneoplastic syndromes associated with thymomas from 1960 to 2019. A secondary search identified additional articles referenced in the articles found in the primary search. Kaplan-Meier and log-rank test were used for time-to-event data analyses.

RESULTS

From 407 articles describing 507 patients, 123 different paraneoplastic syndromes were associated with thymoma. The 5 most common paraneoplastic syndromes were myasthenia gravis, pure red cell aplasia, lichen planus, Good syndrome, and limbic encephalitis. Complete or partial resolution of paraneoplastic syndrome symptoms after surgery was noted in 76% of patients, of whom 21% had a relapse or new paraneoplastic syndrome onset after surgery. The most common adjunctive therapy associated with resolution of paraneoplastic syndrome was corticosteroids (30%). For all patients after surgery, thymoma recurrence was observed in 17% of cases, whereas recurrence of paraneoplastic syndrome was observed in 34% of cases, and both were observed in approximately 11% of cases. The 5- and 10-year overall survivals were 78% and 66%, respectively. Improved overall survival was associated with patients who had total resolution from paraneoplastic syndrome.

CONCLUSIONS

A comprehensive assessment of publications over the past half century suggests that a multimodal treatment approach that includes surgical resection of thymomas is able to achieve paraneoplastic syndrome resolution in a majority of patients. Onset of new paraneoplastic syndromes after surgery is associated with the recurrence of the first paraneoplastic syndrome, and resolution of paraneoplastic syndrome is associated with improved overall survival.

Non-Myasthenia Gravis Immune Syndromes and the Thymus: Is There a Role for Thymectomy?

Thymectomy has long been considered, performed, and discussed for many different nonmyasthenic immune syndromes. Thymectomy is now an established treatment for MG, and has been performed for other immune syndromes with varying degrees of improvement. Although numerous reports document immune syndromes' association with thymoma, few address the role of thymectomy in symptom resolution. This review assesses thymectomy in the various nonmyasthenic immune syndromes for which it has been tried. Based on this review, it seems appropriate to revisit a more active role for thymectomy in pure red cell aplasia, pemphigus, rheumatoid arthritis, autoimmune hemolytic anemia, and ulcerative colitis.

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.

Isoniazid-induced Pure Red Cell Aplasia in a Patient with Sarcoidosis: A Patient Summary and Review of the Literature

A 41-year-old woman treated with isoniazid (INH) for latent tuberculosis infection and an oral corticosteroid for sarcoidosis developed severe anemia two months after initiating INH. A bone marrow examination showed erythroblastopenia, and a diagnosis of INH-induced pure red cell aplasia (PRCA) was made. Her reticulocyte count and hemoglobin levels improved two weeks after discontinuation of INH. A literature review of INH-induced PRCA shows that it occurs very rarely in the context of autoimmune disorders. This report describes a case of INH-induced PRCA occurring in a patient with sarcoidosis.

Pure red cell aplasia and myasthenia gravis: a patient having both autoimmune conditions in the absence of thymoma

This is a patient who was presented initially with symptoms of malaise, tiredness and exertional dyspnoea and found to have a severe normocytic normochromic anaemia with low reticulocyte counts. Bone marrow confirmed the diagnosis of pure red cell aplasia (PRCA) and at the time serology for recent parvovirus infection was positive. He was successfully treated with transfusions and intravenous Ig. Six years later, he had a mild relapse of his PRCA and subsequently developed severe dysphagia and dysarthria which were fatigable. Positive antiacetylcholine receptor antibodies confirmed the diagnosis of myasthenia gravis. The two conditions are both known to be associated with thymoma. Imaging and resection of the thymus gland showed only the presence of a thymic cyst. Treatment with pyrdistogmine and intravenous Ig have kept the patient asymptomatic and in remission. The rare association of the two autoimmune conditions associated in the same patient without thymoma is discussed.

Isoniazid-triggered pure red cell aplasia in systemic lupus erythematosus complicated with myasthenia gravis

A 47-year-old woman who had been treated for systemic lupus erythematosus (SLE) with myasthenia gravis (MG) was admitted to our hospital with acute onset of severe anemia after administration of isoniazid. Pure red cell aplasia (PRCA) was confirmed by elevated serum iron levels, reticulocytopenia and bone marrow aspiration showing a remarkable reduction of erythroblasts. Finally, cyclosporine A successfully improved PRCA. Although both SLE and MG have the potential complication of PRCA, we report here a case of isoniazid-triggered PRCA.

Type AB thymoma accompanied by pure red cell aplasia and Good syndrome with CMV infection of tumor cells

Reported herein is a case of type AB thymoma accompanied by pure red cell aplasia (PRCA) and Good syndrome. The patient was a 55-year-old woman who was found to be anemic and to have an abnormal shadow at the left pulmonary hilus on routine medical examination. Bone marrow aspiration was performed and she was diagnosed as having PRCA. She also had hypogammaglobulinemia. The anemia was temporarily cured with oral prednisolone and cyclosporin A, and the patient underwent total thymectomy. The tumor was type AB thymoma, composed mainly of type A components; widespread spindle cell components showed slight to moderate infiltration of immature T-cells. In addition, CMV inclusion bodies were scattered throughout this tumor. The CMV-infected cells were tumor cells, because they were positive for pancytokeratin and negative for CD34. Several cases of Good syndrome with widespread CMV infection have been reported, but it is extremely rare for CMV-inclusion bodies to be found in tumor cells. No thymoma cases involving CMV infection of tumor cells have been reported.

Cryptogenic middle cerebral artery infarction in pure red cell aplasia

Pure red cell aplasia (PRCA) is a rare hematological disorder characterized by an isolated depletion of erythroid precursors with preservation of other cell lines. Neurological concomitants are not a recognized feature. We report a case of unexplained middle cerebral artery infarction in a 32-year-old woman with PRCA. This concurrence may reflect a predisposition to ischemic stroke in patients with PRCA.

Immunological system status and the appearance of respiratory system disturbances in thymectomized patients

Introduction

Adult-onset thymoma may be responsible for several diseases, such as pure red cell aplasia, myasthenia gravis, and immunodeficiency (Good’s syndrome). Thymectomy does not always improve the patient’s condition, and may even produce additional symptoms. Its pathogenesis is still not entirely understood, but autoimmunological processes and bone marrow defect are the most frequently suggested.

Materials and Methods

Eleven patients (mean age: 56.2 ± 15.5 years) were analyzed 6 months to 10 years after thymectomy due to thymoma as were 25 healthy persons serving as controls. Enzyme-linked immunosorbent assay (ELISA) and flow cytometry techniques were used to evaluate the immunological status of the subjects.

Results

Good’s syndrome was diagnosed in one patient, 4 subjects suffered from myasthenia gravis, and recurrent infections of upper and lower respiratory tract appeared in 9 patients. The immunological analyses (ELISA and flow cytometry) revealed a significantly lower IgG level (p < 0.05), percentage of peripheral blood B lymphocytes (p < 0.0005), and CD4:CD8 ratio (p < 0.05) in thymectomized patients compared with the healthy controls. The percentages of CD4⁺ and CD8⁺ T lymphocytes expressing CD28 antigen were significantly lower in thymectomized patients than in healthy subjects (p < 0.005 and p < 0.01, respectively). The percentage of naïve T helper lymphocytes was significantly lower in the patients than in the control group (p < 0.05).

Conclusions

Immunodeficiency and recurrent infections may be the first symptoms of immunological disturbances after thymectomy in adults. It is suggested that regular medical monitoring of these patients is important in preventing further complications, which may result in irreversible lung tissue destruction.

Early autoimmune complications after thymomectomy in a patient with interstitial lung disease. Case report

Thymoma has been associated with a variety of autoimmune disorders. We report a case of myasthenia gravis and pancytopenia in a 53-year-old man with lymphoepithelial thymoma and interstitial lung disease. Preoperative examination revealed neither hematologic abnormality nor myasthenia gravis. The patient had enteritis prior to thymomectomy, sternal infection in the first month of operation, and urinary infection at the third month. About three months after thymomectomy, he required mechanical ventilation support due to myasthenia gravis-related respiratory failure. One month later, a rapidly progressing pancytopenia developed. The patient died within two weeks of overwhelming septicemia unresponsive to treatment with antibiotics and steroids. The possible onset of myasthenia gravis or pancytopenia after thymomectomy should be kept in mind during follow-up. Recurrent infections in the early stages of thymomectomy may suggest a lethal onset of pancytopenia.

Malignant thymoma complicated by amegakaryocytic thrombocytopenic purpura

We report the case of a 41-year-old man with malignant thymoma complicated by amegakaryocytic thrombocytopenia 10 years after diagnosis of myasthenia gravis. A bone marrow aspirate showed an absence of megakaryocytes with normal maturation and differentiation of myeloid precursors. Three months later, severe neutropenia occurred, and a bone marrow examination confirmed the diagnosis of severe aplastic anemia. Associations between thymoma and myasthenia gravis, between thymoma and pure red cell aplasia, and between thymoma and aplastic anemia are well documented. Amegakaryocytic thrombocytopenia is not a recognized paraneoplastic syndrome complicating thymoma. Amegakaryocytic thrombocytopenia complicating thymoma may be a very early presentation of impending aplastic anemia.

Triad of thymoma, myasthenia gravis and pure red cell aplasia combined with Sjögren’s syndrome

A 36-year-old woman complained of cough and high fever. Computed tomographic scans demonstrated a mediastinal mass. A couple of months later, she developed dryness in her eyes and mouth. Biopsy of the lip confirmed the diagnosis of Sjögren's syndrome. She underwent thymo-thymomectomy. Pathological findings of the mass revealed thymoma. At two months after surgery, she developed ptosis and dysphagia that were compatible with myasthenia gravis. The clinical symptoms were adequately controlled with prednisolone. At eleven months after surgery, she presented with severe anemia, which led to the diagnosis of pure red cell aplasia. The following treatment with cyclosporin caused hemoglobin concentration to rise. However, she continues to suffer from dryness of her eyes and mouth. The case is the first to be reported with Sjögren's syndrome and the triad of thymoma, myasthenia gravis and pure red cell aplasia, and is compared with previously reported cases of the three conditions.

Initial predictors of development of pure red cell aplasia in myasthenia gravis after thymectomy

Pure red cell aplasia (PRCA) is well known to be concomitant with myasthenia gravis (MG), but it is difficult to predict the development of PRCA in patients with MG. Of 135 patients with MG, four (2.9%) had PRCA. All patients developed PRCA after thymectomy during a period when MG was in remission. The frequencies of thymoma, bulbar involvement and high anti-acetylcholine receptor (AChR) antibody levels were significantly higher in four patients with PRCA. Japanese MG patients with these characteristics at presentation were at significant risk for the development of PRCA after thymectomy.

Histologic types of thymoma associated with pure red cell aplasia: a study of five cases including a composite tumor of organoid thymoma associated with an unusual lipofibroadenoma

The histologic type of thymomas associated with pure red cell aplasia (PRCA) has generally been regarded to be predominantly the spindle cell type. The 5 thymomas associated with PRCA we studied showed various histologic types and none of them was a spindle cell thymoma. Some cases reported as spindle cell thymoma associated with PRCA in the literature might not be spindle cell type. The discrepancy could be due to the lack of consensus in the histologic classification of thymomas in the past. Our study showed that thymomas associated with PRCA lacked a strong correlation with a particular histologic type and the pathogenesis of PRCA associated with thymoma did not seem to be related to the histologic type. One of our cases was an unusual composite tumor of an organoid thymoma (WHO type B1) and a hitherto undescribed "lipofibroadenoma." The clinical outcome was influenced by the invasive character and the histologic type of the thymoma.