Thymoma with Concomitant Pure Red Cell Aplasia, Good's Syndrome and Myasthenia Gravis Responding to Rituximab

Eculizumab in thymoma-associated myasthenia gravis: a real-world cohort study

Background

Thymoma-associated myasthenia gravis (TAMG) is a subtype of myasthenia gravis (MG) that is associated with more severe symptoms and a relatively poor prognosis. Eculizumab, an inhibitor to target human C5 component of the complement cascade, is considered a treatment option for refractory generalized MG (gMG).

Objectives

To explore the safety and efficacy of eculizumab in patients with TAMG.

Design

This is an observational multicenter real-world cohort study to assess TAMG who were treated with eculizumab from June 2023 to June 2024.

Data sources and methods

Clinical features associated with thymoma-associated multi-organ autoimmunity (TAMA), Myasthenia Gravis Activities of Daily Living (MG-ADL) score, and the incidence of treatment-emergent adverse events (TEAEs) were prospectively collected.

Results

Overall, 42 patients with gMG were treated with eculizumab at 5 research centers, of whom 22 patients with TAMG were finally included. This cohort had a mean age of 51.5 ± 12.1 years and an average disease duration of 4.0 ± 4.3 years. Regarding thymomas, the World Health Organization (WHO) histological classification was primarily B2 and B3 (63.7%), and Masaoka staging was predominantly IV (45.5%). Nine participants (40.9%) switched from efgartigimod to eculizumab aiming at a better clinical improvement and reducing steroid use. By week 12, the MG-ADL score decreased to 4.8 ± 4.7 (baseline: 11.7 ± 6.0), and the corticosteroid dose reduced to 23.2 ± 26.5 mg (baseline: 41.8 ± 63.9 mg). Two patients with TAMA showed significant improvement in skin lesions and thrombocytopenia. Two TEAEs were recorded including COVID-19 and herpes labialis infection. Four patients (18.2%) died of respiratory or circulatory failure owing to thymoma metastasis.

Conclusion

This real-world study demonstrates the efficacy of eculizumab in achieving symptom control and corticosteroid reduction for TAMG. It may also be a therapeutic option for refractory TAMG and TAMA.

Trial registration

NCT04535843.

Good syndrome combined with multiple microbial pulmonary infections: case report and review of the literature

Good syndrome (GS), a rare acquired immunodeficiency disorder characterized by thymoma and hypogammaglobulinemia, predisposes individuals to recurrent infections. This study reports a case of a 37-year-old male GS with multiple pulmonary infections and reviews relevant literature. The patient, with a history of thymoma resection, experienced multiple hospitalizations due to lung infections and neutropenia. The alveolar lavage fluid was detected by macro-genomic sequencing (NGS) to detect multiple pathogens, and targeted anti-infective and immunity-enhancing treatments led to improved symptoms and normal neutrophil counts. A literature review of 98 case reports from 2000 to 2023 was conducted, summarizing the associated diseases and pathogens in GS patients. Regular immunoglobulin monitoring in thymoma patients is essential for early GS diagnosis. When empirical antimicrobial therapy fails, mNGS for pathogen detection and targeted therapy are crucial, and regular IVIG injections can reduce infection rates in GS patients.

Good's Syndrome With Pure Red Cell Aplasia and Subclinical Myasthenia Gravis: A Case Report and Review of Literature

Good's syndrome is a pathologic condition characterized by thymoma and immunoglobulin disorder. Here, we report a rare case of a patient with Good's syndrome with simultaneous pure red cell aplasia (PRCA) and subclinical myasthenia gravis with detectable serum anti-acetylcholine receptor antibody (AChR Ab). While thymectomy did not result in the improvement of any paraneoplastic syndromes, cyclosporine A (CsA) treatment successfully improved PRCA; however, hypoglobulinemia was not recovered, and anti-AchR Ab did not disappear by CsA treatment in our case. A review of the literature on simultaneous Good's syndrome with PRCA also suggested the efficacy of CsA on PRCA but not hypoglobulinemia, suggesting the distinct underlying mechanisms between these two paraneoplastic symptoms with thymoma. Future research is needed to understand the mechanism underlying this rare pathologic condition and to generate appropriate treatment.

Case Report: Roxadustat in Combination With Rituximab Was Used to Treat EPO-Induced Pure Red Cell Aplasia

Recombinant human erythropoietin (rHuEPO) is a drug given to patients who have low hemoglobin related to chronic kidney disease or other anemia-related diseases. Some patients who receive rHuEPO repeatedly develop anti-rHuEPO-neutralizing antibodies, leading to the occurrence of pure red cell aplasia (PRCA). PRCA associated with rHuEPO includes severe rHuEPO resistance, blood transfusion dependence, high serum ferritin, severe reticulocytopenia, and presence of anti-rHuEPO antibody. However, the optimal treatment of erythropoietin (EPO)-induced PRCA is unclear. Therapeutic options against it remain a major clinical challenge. Herein we report on 2 male patients with PRCA during rHuEPO treatment, who received a combination therapy of roxadustat plus rituximab but had completely different clinical outcomes. The results obtained in this study show that roxadustat in combination with rituximab could be one of the treatment options for EPO-induced PRCA, but the treatment efficacy can vary from one individual to another. Additionally, we recommend starting reticulocyte monitoring and immunosuppressive agent therapy as early as possible to shorten the course of the disease and improve the outcomes of the patients.

When the Good Syndrome Goes Bad: A Systematic Literature Review

Background

Good syndrome is a rare adult-onset immunodeficiency characterized by thymoma and hypogammaglobulinemia. Its clinical manifestations are highly heterogeneous, ranging from various infections to autoimmunity.

Objective

This study was to summarize patient characteristics, identify prognostic factors and define clinical subgroups of Good syndrome.

Methods

A systematic literature review was conducted to include patients with Good syndrome identified in PubMed, Embase and Cochrane databases between January 2010 and November 2020. Logistic and Cox regressions were used to identify prognostic factors impacting outcomes. Clinical subgroups were defined by multiple correspondence analysis and unsupervised hierarchical clustering. A decision tree was constructed to characterize the subgroup placement of cases.

Results

Of 162 patients included in the current study, the median age at diagnosis was 58 years and 51% were male. Type AB was the most common histological subtype of thymoma, and infections as well as concurrent autoimmune disorders were identified in 92.6% and 51.2% patients, respectively. Laboratory workup showed typical findings of combined immunodeficiency. Thymoma status (odds ratio [OR] 4.157, confidence interval [CI] 1.219-14.177, p = 0.023), infections related to cellular immunity defects (OR 3.324, 95% CI 1.100-10.046, p = 0.033), infections of sinopulmonary tract (OR 14.351, 95% CI 2.525-81.576, p = 0.003), central nerve system (OR 6.403, 95% CI 1.205-34.027, p = 0.029) as well as bloodstream (OR 6.917, 95% CI 1.519-31.505, p = 0.012) were independent prognostic factors. The 10-year overall survival was 53.7%. Cluster analysis revealed three clinical subgroups with distinct characteristics and prognosis (cluster 1, infections related to cellular immunity defects; cluster 2, infections related to other immunity defects; cluster 3, infections related to humoral and phagocytic immunity defects). A decision tree using infection types (related to humoral and cellular immunity defects) could place patients into corresponding clusters with an overall correct prediction of 72.2%.

Conclusions

Infection type and site were the main prognostic factors impacting survival of patients with Good syndrome. We identified three subgroups within Good syndrome associated with distinct clinical features, which may facilitate the study of underlying pathogenesis as well as development of targeted therapy.

Clinical manifestations and long-term prognosis of Good syndrome: Results from a single-center cohort study from China

OBJECTIVE

To describe clinical features and long-term prognosis in patients with Good syndrome (GS).

METHODS

We retrospectively reviewed medical records of GS patients at Peking Union Medical College Hospital from January 2001 to May 2019. Data regarding clinical manifestations and treatments were collected. Patients were routinely followed-up via clinical and telephone interviews, and survival analysis was performed with Kaplan-Meier analysis.

RESULTS

Twenty-four patients were identified, including eight males and 16 females, with a median age at diagnosis of 58 years (interquartile range [IQR], 52-62 years). Twelve patients (50%) had autoimmune manifestations. Multi-organ involvements included musculoskeletal (37.5%), respiratory (33.3%), gastrointestinal (29.2%), hematologic (29.2%) systems, et.al. Infections were detected in 23 (95.8%) patients, mostly located in lung (69.6%), blood (26.1%), and gastrointestinal tract (21.7%). Thymectomy was performed in 23 patients, with the most common histology of type AB (10, 47.6%). Twenty-one patients were consecutively followed-up with a median follow-up of 84 (IQR, 48-116) months and 11 (52.4%) died, mainly due to infection (8/11, 72.7%). The 5- and 10-year survival rates were 90% (95% confidence interval [CI], 77.8-100%) and 38.5% (95% CI, 19.6-75.5%), respectively.

CONCLUSION

GS patients tended to present with various infections and autoimmune manifestations. The 10-year survival rate from the Chinese population was poor, mainly due to infections.