Sequential development of diffuse panbronchiolitis and myasthenia gravis after thymectomy for thymic neoplasm: a case report.

BACKGROUND: Myasthenia gravis (MG) is the most common paraneoplastic disorder associated with thymic neoplasms. MG can develop after thymectomy, and this condition is referred to post-thymectomy myasthenia gravis (PTMG). Diffuse panbronchiolitis (DPB), is a rare form of bronchiolitis and is largely restricted to East Asia, has been reported in association with thymic neoplasms. Only three cases of combined MG and DPB have been reported in the literature. CASE PRESENTATION: A 45-year-old Taiwanese woman presented to our hospital with productive cough, rhinorrhea, anosmia, ear fullness, shortness of breath, and weight loss. She had a history of thymoma, and she underwent thymectomy with adjuvant radiotherapy 7 years ago. Chest computed tomography scan revealed diffuse bronchitis and bronchiolitis. DPB was confirmed after video-assisted thoracoscopic surgery lung biopsy, and repeated sputum cultures grew Pseudomonas aeruginosa. She has been on long-term oral azithromycin therapy thereafter. Intravenous antipseudomonal antibiotics, inhaled amikacin, as well as oral levofloxacin were administered. Three months after DPB diagnosis, she developed ptosis, muscle weakness, and hypercapnia requiring the use of noninvasive positive pressure ventilation. MG was diagnosed based on the acetylcholine receptor antibody and repetitive stimulation test results. Her muscle weakness gradually improved after pyridostigmine and corticosteroid therapies. Oral corticosteroids could be tapered off ten months after the diagnosis of MG. She is currently maintained on azithromycin, pyridostigmine, and inhaled amikacin therapies, with intravenous antibiotics administered occasionally during hospitalizations for respiratory infections. CONCLUSIONS: To our knowledge, this might be the first case report of sequential development of DPB followed by PTMG. The coexistence of these two disorders poses a therapeutic challenge for balancing infection control for DPB and immunosuppressant therapies for MG.

Thymic MALT lymphoma associated with Sjögren's syndrome with postoperative cardiac tamponade and acute pleuritis: a case report.

BACKGROUND: Thymic mucosa-associated lymphoid tissue (MALT) lymphoma is rare and is known to be associated with Sjögren's syndrome (SjS). SjS is rarely accompanied by serositis. Here, we describe the first case of postoperative cardiac tamponade and acute pleuritis in a patient with thymic MALT lymphoma associated with SjS. CASE PRESENTATION: A 33-year-old woman with SjS presented with an anterior mediastinal mass on chest computed tomography, which was performed for further examination of the condition. Suspecting a thymic MALT lymphoma or thymic epithelial tumor, total thymectomy was performed. The mediastinal mass was histopathologically diagnosed as a thymic MALT lymphoma. The patient was discharged with a good postoperative course but visited the hospital 30 days after surgery for dyspnea. Cardiac tamponade was observed and drainage was performed. Four days after pericardial drainage, chest radiography revealed massive left pleural effusion, and thoracic drainage was performed. The patient was diagnosed with serositis associated with SjS and treated with methylprednisolone, which relieved cardiac tamponade and pleuritis. CONCLUSIONS: Surgical invasion of thymic MALT lymphomas associated with SjS may cause serositis. Postoperative follow-up should be conducted, considering the possibility of cardiac tamponade or acute pleuritis due to serositis as postoperative complications.

Effects of antibiotics, hospitalisation and surgical complications on self-reported immunological vulnerability following paediatric open-heart surgery and thymectomy: a single-centre retrospective cohort study.

BACKGROUND: Partial or complete thymectomy is routinely performed in paediatric open-heart surgeries when treating congenital heart defects. Whether or not thymectomised children require systematic immunological monitoring later in life is unknown. The objective of this study was to investigate the effects of preoperatively and postoperatively used antibiotics, hospitalisation and surgical complications on self-reported immunological vulnerability in paediatric patients with early thymectomy to better recognise the patients who could benefit from immunological follow-up in the future. METHODS: We conducted a retrospective cohort study, including 98 children and adolescents aged 1-15 years, who had undergone an open-heart surgery and thymectomy in infancy and who had previously answered a survey regarding different immune-mediated symptoms and diagnoses. We performed a comprehensive chart review of preoperative and postoperative factors from 1 year preceding and 1 year following the open-heart surgery and compared the participants who had self-reported symptoms of immunological vulnerability to those who had not. RESULTS: The median age at primary open-heart surgery and thymectomy was 19.5 days in the overall study population (60% men, n=56) and thymectomies mainly partial (80%, n=78). Broad-spectrum antibiotics were more frequently used preoperatively in participants with self-reported immunological vulnerability (OR=3.05; 95% CI 1.01 to 9.23). This group also had greater overall use of antibiotics postoperatively (OR=3.21; 95% CI 1.33 to 7.76). These findings were more pronounced in the subgroup of neonatally operated children. There was no statistically significant difference in the duration of intensive care unit stay, hospitalisation time, prevalence of severe infections, surgical complications or glucocorticoid use between the main study groups. CONCLUSION: Antimicrobial agents were more frequently used both preoperatively and postoperatively in thymectomised children with self-reported immunological vulnerability after thymectomy. Substantial use of antimicrobial agents early in life should be considered a potential risk factor for increased immunological vulnerability when evaluating the significance of immune-mediated symptom occurrence in thymectomised paediatric patients.

Does Surgical Removal of the Thymus Have Deleterious Consequences?

The role of immunosenescence, particularly the natural process of thymic involution during aging, is increasingly acknowledged as a factor contributing to the development of autoimmune diseases and cancer. Recently, a concern has been raised about deleterious consequences of the surgical removal of thymic tissue, including for patients who undergo thymectomy for myasthenia gravis (MG) or resection of a thymoma. This review adopts a multidisciplinary approach to scrutinize the evidence concerning the long-term risks of cancer and autoimmunity postthymectomy. We conclude that for patients with acetylcholine receptor antibody-positive MG and those diagnosed with thymoma, the removal of the thymus offers prominent benefits that well outweigh the potential risks. However, incidental removal of thymic tissue during other thoracic surgeries should be minimized whenever feasible.

The rate of QMGS change predicts recurrence after thymectomy in myasthenia gravis.

OBJECTIVE: To investigate the relationship between short-term changes in quantitative myasthenia gravis score (QMGS) after thymectomy and postoperative recurrence in myasthenia gravis (MG) patients without thymoma. METHODS: A retrospective observational cohort study. The QMGS of 44 patients with non-thymomatous MG were evaluated before and 1 month after thymectomy, and the frequency and time of postoperative recurrence were recorded. The reduction rate of QMGS (rr-QMGS) was defined as (QMGS one week before thymectomy - QMGS one month after thymectomy)/ QMGS one week before thymectomy × 100 %, as an indicator of short-term symptom change after thymectomy. The receiver operating characteristic (ROC) curve was established to determine an appropriate cut-off value of rr-QMGS for distinguishing postoperative recurrence. Multivariate Cox regression analysis was applied to predict postoperative recurrence. RESULTS: Postoperative recurrence occurred in 21 patients (30 times in total) during follow-up. The mean annual recurrence rate was 3.98 times/year preoperatively and 0.30 times/year postoperatively. ROC analysis determined the cut-off value of rr-QMGS was 36.7 % (sensitivity 90.5 %, specificity 52.2 %). Multivariate Cox regression analysis showed that rr-QMGS＜36.7 % (hazard rate[HR]6.251, P = 0.014) is positive predictor of postoperative recurrence. Kaplan-Meier analysis showed that postoperative recurrence time was earlier in the low rr-QMGS group than in the high rr-QMGS group (12.62 vs. 36.60 months, p = 0.005). CONCLUSIONS: Low rr-QMGS is associated with early postoperative recurrence. Rr-QMGS can be used to predict postoperative recurrence of non-thymomatous MG.

Cardiac herniation post left upper lobectomy and thymectomy: a case report.

BACKGROUND: Cardiac herniation occurs when there is a residual pericardial defect post thoracic surgery and is recognised as a rare but fatal complication. It confers a high mortality and requires immediate surgical correction upon recognition. We present a case of cardiac herniation occurring post thymectomy and left upper lobectomy. CASE PRESENTATION: Initial presentation: A 48-year-old male, hypertensive smoker presented with progressive breathlessness and was found to have a left upper zone mass confirmed on CT biopsy as carcinoid of unclear origin. PET-CT revealed avidity in a left anterior mediastinal area, left upper lobe (LUL) lung mass, mediastinal lymph nodes, and a right thymic satellite nodule. Intraoperatively: Access via left thoracotomy and sternotomy. The LUL tumour involved the left thymic lobe (LTL), left superior pulmonary vein (LSPV), left phrenic nerve and intervening mediastinal fat and pericardium, which were resected en-masse. The satellite nodule in the right thymic lobe (RTL) was adjacent to the junction between the left innominate vein and superior vena cava (SVC). The pericardium was resected from the SVC to the left atrial appendage. Clinical deterioration: Initially the patient was doing well clinically on day 1, however there was sudden bradycardia, hypotension, clamminess, and oligoanuria, with raised central venous pressures and troponins. ECG: no capture in leads V1-2, but positive deflections seen on posterior leads. Echo: no acoustic windows, but good windows seen posteriorly. CXR: left mediastinal shift. Redo operation: After initial resuscitation and stabilisation on the intensive care unit, on day 2 a redo-sternotomy revealed cardiac herniation into the left thoracic cavity with the left ventricular apex pointing towards the spine, and inferior caval kinking. After reduction and repair of the pericardial defect with a fenestrated GoreTex patch, the patient recovered well with complete resolution of the ECG and CXR. CONCLUSION: Cardiac herniation can even occur following sub-pneumonectomy lung resections and should be considered as a differential when faced with a sudden clinical deterioration, warranting early surgical correction.

Pneumonia, wheezing and asthma were more common in children after thymectomy due to open-heart surgery.

AIM: This nationwide study evaluated the clinical impact that an early thymectomy, during congenital heart defect (CHD) surgery, had on the health of children and adolescents. METHODS: The subjects were patients aged 1-15 years who had undergone CHD surgery at the University Children's Hospital, Helsinki, where all CHD surgery in Finland is carried out, from 2006 to 2018. The parents or the cases and population-based controls, matched for sex, age and hospital district, completed electronic questionnaires. We excluded those with low birth weights or a known immunodeficiency. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) were calculated for prespecified outcomes. RESULTS: We received responses relating to 260/450 (58%) cases and 1403/4500 (31%) controls and excluded 73 cases with persistent cardiac or respiratory complaints after surgery. The CHD group reported more recurrent hospitalisations due to infections (aOR 6.3, 95% CI 3.0-13) than the controls and more pneumonia episodes (aOR 3.5, 95% CI 2.1-5.6), asthma (aOR 2.5, 95% CI 1.5-4.1) and wheezing (aOR 2.1, 95% CI 1.5-2.9). CONCLUSION: Hospitalisation due to infections, pneumonia, wheezing and asthma was more common in children after a thymectomy due to open-heart surgery than population-based controls, underlining the importance of immunological follow-ups.

Myasthenia Gravis with Toxic Goiter: Challenges with Management in a Low-Resource Setting in Africa; Review of Literature and Case Report.

ABSTRACT: Myasthenia gravis (MG) is an antibody-mediated autoimmune disease with the cardinal feature being exertional voluntary skeletal muscle weakness and fatigability. It can be an isolated finding or in association with other autoimmune conditions such as Hashimoto's thyroiditis, Graves' disease, systemic lupus erythematosus (SLE), or rheumatoid arthritis. Thymectomy is recommended for most patients with MG whose symptoms begin before the age of 60 years. Patients with thymoma or thymic hyperplasia do respond to thymectomy compared to those without thymoma or enlarged thymus. Those with enlarged goiter would benefit from thyroidectomy. The management of these patients requires a multidisciplinary approach as performed in a low-resource setting. We are reporting the case of a 24-year-old who presented with MG with toxic goiter and had good control on medication. A computed tomography scan of the chest showed a superior mediastinal mass and a soft tissue scan of the neck was done which showed a diffusely enlarged thyroid gland. She subsequently had thymectomy and subtotal thyroidectomy with a satisfactory outcome. We highlight this case to show that MG with thymoma and goiter could coexist. Reports of such findings are infrequently reported in our environment.

Steroid-resistant minimal change nephrotic syndrome associated with thymoma treated effectively with rituximab following thymectomy and cyclosporine: a case report.

BACKGROUND: Minimal change nephrotic syndrome (MCNS) can be complicated by thymoma; however, no standard therapy for thymoma-associated MCNS has yet been established. We herein describe a case of steroid-resistant MCNS associated with thymoma, treated effectively with rituximab. CASE PRESENTATION: A 71-year-old Japanese man was referred to our department with severe proteinuria (20 g/gCr). Renal biopsy showed minimal change disease and computed tomography revealed an anterior mediastinal mass. Based on these findings, he was diagnosed with thymoma-associated MCNS. He was treated with oral prednisolone (50 mg/day) and cyclosporine, and underwent thymectomy and plasma exchange. However, no improvement in proteinuria was observed. He therefore received intravenous rituximab 500 mg, resulting in a marked decrease in proteinuria from 5328 to 336 mg/day after 1 week. CONCLUSIONS: This case suggests that rituximab might be an effective therapy in patients with steroid-resistant MCNS associated with thymoma.

Germinal centers are associated with postthymectomy myasthenia gravis in patients with thymoma.

BACKGROUND AND PURPOSE: Germinal centers (GCs) can be observed in the thymic tissues of patients with thymoma-associated myasthenia gravis (MG). Although an association between thymic GCs and MG has been suggested, it is unknown whether the presence of GCs could predict the development of MG after the resection of thymoma, known as postthymectomy MG. METHODS: We conducted a retrospective analysis of previously nonmyasthenic patients who underwent surgical removal of the thymoma. All available thymic tissue slides were rereviewed by a pathologist to assess for GCs. Patients were classified into GC-positive and GC-negative groups based on the presence of GCs. The incidence of postthymectomy MG was compared between the two groups, and the risk factors for postthymectomy MG were assessed. RESULTS: Of the 196 previously nonmyasthenic patients who underwent thymoma resection, 21 were GC-positive, whereas 175 were GC-negative. Postthymectomy MG developed in 11 (5.6%) patients and showed a higher incidence in the GC-positive group than in the GC-negative group (33.3% vs. 2.3%, p < 0.001). No postoperative radiotherapy and the presence of GCs were risk factors for postthymectomy MG in the univariate analysis. In multivariate analysis, invasive thymoma (hazard ratio [HR] = 9.835, 95% confidence interval [CI] = 1.358-105.372), postoperative radiotherapy (HR = 0.160, 95% CI = 0.029-0.893), and presence of GCs (HR = 15.834, 95% CI = 3.742-67.000) were significantly associated with postthymectomy MG. CONCLUSIONS: Thymic GCs may be a significant risk factor for postthymectomy MG. Even in patients with thymoma who do not show clinical symptoms of MG, postthymectomy MG should be considered, especially if thymic GCs are observed.

Immunology of THymectomy And childhood CArdiac transplant (ITHACA): protocol for a UK-wide prospective observational cohort study to identify immunological risk factors of post-transplant lymphoproliferative disease (PTLD) in thymectomised children.

INTRODUCTION: Paediatric heart transplant patients are disproportionately affected by Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disease (PTLD) compared with other childhood solid organ recipients. The drivers for this disparity remain poorly understood. A potential risk factor within this cohort is the routine surgical removal of the thymus-a gland critical for the normal development of T-lymphocyte-mediated antiviral immunity-in early life, which does not occur in other solid organ transplant recipients. Our study aims to describe the key immunological differences associated with early thymectomy, its impact on the temporal immune response to EBV infection and subsequent risk of PTLD. METHODS AND ANALYSIS: Prospective and sequential immune monitoring will be performed for 34 heart transplant recipients and 6 renal transplant patients (aged 0-18 years), stratified into early (<1 year), late (>1 year) and non-thymectomy groups. Peripheral blood samples and clinical data will be taken before transplant and at 3, 6, 12 and 24 months post-transplant. Single cell analysis of circulating immune cells and enumeration of EBV-specific T-lymphocytes will be performed using high-dimensional spectral flow cytometry with peptide-Major Histocompatibilty Complex (pMHC) I/II tetramer assay, respectively. The functional status of EBV-specific T-lymphocytes, along with EBV antibodies and viral load will be monitored at each of the predefined study time points. ETHICS AND DISSEMINATION: Ethical approval for this study has been obtained from the North of Scotland Research Ethics Committee. The results will be disseminated through publications in peer-reviewed journals, presentations at scientific conferences and patient-centred forums, including social media. TRIAL REGISTRATION NUMBER: ISRCTN10096625.

Health Consequences of Thymus Removal in Adults.

BACKGROUND: The function of the thymus in human adults is unclear, and routine removal of the thymus is performed in a variety of surgical procedures. We hypothesized that the adult thymus is needed to sustain immune competence and overall health. METHODS: We evaluated the risk of death, cancer, and autoimmune disease among adult patients who had undergone thymectomy as compared with demographically matched controls who had undergone similar cardiothoracic surgery without thymectomy. T-cell production and plasma cytokine levels were also compared in a subgroup of patients. RESULTS: After exclusions, 1420 patients who had undergone thymectomy and 6021 controls were included in the study; 1146 of the patients who had undergone thymectomy had a matched control and were included in the primary cohort. At 5 years after surgery, all-cause mortality was higher in the thymectomy group than in the control group (8.1% vs. 2.8%; relative risk, 2.9; 95% confidence interval [CI], 1.7 to 4.8), as was the risk of cancer (7.4% vs. 3.7%; relative risk, 2.0; 95% CI, 1.3 to 3.2). Although the risk of autoimmune disease did not differ substantially between the groups in the overall primary cohort (relative risk, 1.1; 95% CI, 0.8 to 1.4), a difference was found when patients with preoperative infection, cancer, or autoimmune disease were excluded from the analysis (12.3% vs. 7.9%; relative risk, 1.5; 95% CI, 1.02 to 2.2). In an analysis involving all patients with more than 5 years of follow-up (with or without a matched control), all-cause mortality was higher in the thymectomy group than in the general U.S. population (9.0% vs. 5.2%), as was mortality due to cancer (2.3% vs. 1.5%). In the subgroup of patients in whom T-cell production and plasma cytokine levels were measured (22 in the thymectomy group and 19 in the control group; mean follow-up, 14.2 postoperative years), those who had undergone thymectomy had less new production of CD4+ and CD8+ lymphocytes than controls (mean CD4+ signal joint T-cell receptor excision circle [sjTREC] count, 1451 vs. 526 per microgram of DNA [P = 0.009]; mean CD8+ sjTREC count, 1466 vs. 447 per microgram of DNA [P<0.001]) and higher levels of proinflammatory cytokines in the blood. CONCLUSIONS: In this study, all-cause mortality and the risk of cancer were higher among patients who had undergone thymectomy than among controls. Thymectomy also appeared be associated with an increased risk of autoimmune disease when patients with preoperative infection, cancer, or autoimmune disease were excluded from the analysis. (Funded by the Tracey and Craig A. Huff Harvard Stem Cell Institute Research Support Fund and others.).

Combined effect of thymectomy on myasthenia gravis in patients with concomitant auto-immune diseases: a 22-year single-center experience.

Myasthenia gravis (MG) is an autoimmune disease (AD), and patients with MG often have other types of ADs. We analyzed the prognosis of patients with MG complicated by AD after thymectomy. A retrospective analysis was performed for patients with MG complicated by ADs treated surgically in our center over the past 22 years, and their general condition and follow-up data were collected and analyzed. 33 patients were included totally. 28 patients displayed improvement or even complete recovery of MG, and 23 of 36 ADs revealed improvement or even complete recovery. The prognosis of MG is significantly correlated with the duration of postoperative follow-up time (p = 0.028), and in patients with thymoma, the larger the tumor diameter, the better the prognosis of MG (p = 0.026). Thymic hyperplasia patients were predominantly female (p = 0.049) and young (p < 0.001). The most common concomitant AD in this study was a thyroid-associated AD, which was associated with thymic hyperplasia (p < 0.001), Osserman type I MG (p < 0.001), and young age (p < 0.001). Thymectomy had a good therapeutic effect on MG complicated by AD, and there was a close correlation between surgery, thymus, MG, and ADs.

Thymectomy in severe (Myasthenia Gravis Foundation of America classes IV-V) generalized myasthenia gravis: is the game really worth the candle?

OBJECTIVES: Total thymectomy in addition to medical treatment is an accepted standard therapy for myasthenia gravis (MG). Patients with severe generalized MG present life-threatening events, poor prognosis and higher risk of postoperative myasthenic crisis. The aim of our study is to investigate neurological and surgical results in patients with Myasthenia Gravis Foundation of America (MGFA) class IV and V MG following thymectomy. METHODS: Data on 76 MG patients with preoperative MGFA classes IV and V who underwent thymectomy were retrospectively collected. Primary end points included short-term surgical outcomes and long-term neurological results including the achievement of complete stable remission and any improvement as defined by MGFA Post-Intervention Status criteria. RESULTS: There were 27 (35.5%) males and 49 (64.5%) females; 53 (69.7%) were classified as MGFA class IV and 23 (30.3%) as class V. Thymectomy was performed through sternotomy in 25 (32.9%) patients, Video-assisted thoracic surgery (VATS) in 5 (6.6%) and Robot-assisted thoracic surgery (RATS) in 46 (60.5%). The median operative time was 120 (interquartile range: 95; 148) min. In-hospital mortality was observed in 1 (1.3%) patient and postoperative complications in 14 (18.4%) patients. The median postoperative hospital stay was 4 (interquartile range: 3; 6) days. Pathological examination revealed 31 (40.8%) thymic hyperplasia/other benign and 45 (59.2%) thymomas. Cumulative complete stable remission and improvement probabilities were 20.6% and 83.7% at 5 years and 66.9% and 97.6% at 10 years, respectively. A significant improvement rate was found in patients with age at the time of thymectomy of ≤50 years (P = 0.0236), MGFA class V (P = 0.0154) and acetylcholine receptor antibodies positivity (P = 0.0152). CONCLUSIONS: Thymectomy in patients with severe MG yields good perioperative outcomes and satisfactory long-term neurological improvement, especially for patients younger than 50 years, with MGFA class V and anti-AChR+ MG.

Early Postoperative Results after Thymectomy for Thymic Cancer: A Single-Institution Experience.

BACKGROUND: Surgery for thymic cancers is considered the key of curative treatment. Preoperative patients' characteristics and intraoperative features might influence postoperative outcome. We aim to verify short-term outcomes and possible risk factors for complications after thymectomy. METHODS: We retrospectively investigated patients undergoing surgery for thymoma or thymic carcinoma in the period between January 1, 2008, and December 31, 2021, in our department. Preoperative features, surgical technique (open, bilateral VATS, RATS), intraoperative characteristics and incidence of postoperative complications (PC) were analyzed. RESULTS: We included in the study 138 patients. Open surgery was performed in 76 patients (55.1%), in 36 VATS (26.1%) and in 26 RATS (36.1%). Resection of one or more adjacent organs due to neoplastic infiltration was required in 25 patients. PC appeared in 25 patients (52% Clavien-Dindo grade I, 12% grade IVa). Open surgery had a higher incidence of PC (p < 0.001), longer postoperative in-hospital stay (p = 0.045) and larger neoplasm (p = 0.006). PC were significant related to pulmonary resection (p = 0.006), phrenic nerve resection (p = 0.029), resection of more than one organ (p = 0.009) and open surgery (p = 0.001), but only extended surgery of more organs was confirmed as independent prognostic factor for PC (p = 0.0013). Patients with preoperative myasthenia symptoms have a trend toward stage IVa complications (p = 0.065). No differences were observed between outcomes of VATS and RATS. CONCLUSIONS: Extended resections are related to a higher incidence of PC, while VATS and RATS guarantee a lower incidence of PC and shorter postoperative stay even in patients that require extended resections. Symptomatic myasthenia patients might have a higher risk toward more severe complications.

Nomogram for predicting the risk of postoperative myasthenic crisis in patients with thymectomy.

OBJECTIVE: This study aimed to develop and validate internally a clinical predictive model, for predicting myasthenic crisis within 30 days after thymectomy in patients with myasthenia gravis. METHODS: Eligible patients were enrolled between January 2015 and May 2019. The primary outcome measure was postoperative myasthenic crisis (POMC). A predictive model was constructed using logistic regression and presented in a nomogram. The area under the receiver operating characteristic curve (AUC) was calculated to examine the performance. The study population was divided into high- and low-risk groups according to Youden index. Calibration curves with 1000 replications bootstrap resampling were plotted to visualize the calibration of the nomogram. Decision curve analyses (DCA) with 1000 replications bootstrap resampling were performed to evaluate the clinical usefulness of the model. RESULTS: A total of 445 patients were enrolled. Five variables were screened including thymus imaging, onset age, MGFA classification, preoperative treatment regimen, and surgical approach. The model exhibited moderate discriminative ability with AUC value 0.771. The threshold probability was 0.113, which was used to differentiate between high- and low-risk groups. The sensitivity and specificity were 72.1% and 77.1%, respectively. The high-risk group had an 8.70-fold higher risk of POMC. The calibration plot showed that when the probability was between 0 and 0.5, the deviation calibration curve of the model was consistent with the ideal curve. INTERPRETATION: This nomogram could assist in identifying patients at higher risk of POMC and determining the optimal surgical time for these patients.

Effects of comorbid diseases on clinical outcomes in patients with myasthenia gravis.

BACKGROUND: This cross-sectional study was undertaken to evaluate the existence and distribution of comorbid disorders among myasthenia gravis (MG) patients according to subgroups and to identify the effects of the comorbid diseases of MG patients on clinical outcomes. METHODS: The patients were divided into six subgroups according to serum antibodies, age at onset, and thymoma presence. All patients were treated in line with the International Consensus Guidance for Management of Myasthenia Gravis. To assess the clinical outcome after treatment for MG, we used the MGFA Post-intervention Status. In generalized MG patients, the good prognosis group included patients who were classified as having minimal-manifestation status or better. In ocular MG patients, the remission subgroup included patients who were classified as having complete stable remission or pharmacological remission status. RESULTS: Our study included 168 MG patients, 85 were female while 83 were male. Comorbid diseases were present in 124 (73.8%) MG cases. After at least 1 year of follow-up, 106 (86.8%) of the generalized MG patients were in the good prognosis group and 16 (13.2%) generalized MG patients were in the poor prognosis group. 27 (58.6%) ocular MG patients were in the remission group and 19 (41.3%) ocular MG patients were in the non-remission group. Hypertension increased the risk of poor prognosis by 3.55-fold among patients with generalized MG and type 2 DM increased the risk of not achieving remission by 9.32-fold among patients with ocular MG. CONCLUSION: Hypertension and type 2 DM had negative effects on the clinical outcomes of MG.

Thymectomy in thymomatous generalized myasthenia gravis: An analysis of the prognosis and risk factors.

BACKGROUND AND PURPOSE: This study investigated the postthymectomy outcomes and factors affecting the prognosis of thymomatous generalized myasthenia gravis (TGMG). METHODS: Clinical records of 86 patients with TGMG who underwent thymectomy at our institution between 2012 and 2020 were retrospectively reviewed. Predictors of complete stable remission (CSR) and exacerbation were analyzed using multivariate regression analysis. RESULTS: A total of 16 patients achieved CSR, four achieved pharmacological remission, six exhibited deterioration, and eight died of myasthenia gravis (MG; mean follow-up = 75.1 months). Male sex (p = 0.049) and disease duration < 11.5 weeks before surgery (p = 0.003) were significant positive predictors of CSR. Onset age < 52.8 years and symptoms of ocular and limb muscle weakness had a higher CSR rate than onset age > 52.8 years (p = 0.056) and symptoms of bulbar muscles (p = 0.071). Female patients had a significant higher risk of exacerbation (p = 0.042). CONCLUSIONS: Male sex and disease duration < 11.5 weeks were independent predictors of CSR in TGMG postthymectomy. Onset age < 52.8 years and ocular and limb muscle weakness at onset were associated with a higher probability of achieving CSR than onset age > 52.8 years and bulbar muscle weakness. Female sex was an independent predictor of MG symptom exacerbation in TGMG postthymectomy.

Comparison of Short-Term Post-Thymectomy Outcomes by Time-Weighted Dosages of Drug Requirements between Thymoma and Non-Thymoma Myasthenia Gravis Patients.

(1) Background: Early thymectomy is suggested in all clinically indicated myasthenia gravis (MG) patients. However, short-term clinical response after thymectomy in MG patients has been limitedly described in the literature. This study aimed to compare the 5-year post-thymectomy outcomes between thymoma (Th) and non-thymoma (non-Th) MG patients. (2) Methods: MG patients aged ≥18 years who underwent transsternal thymectomy and had tissue histopathology reports in Songklanagarind Hospital between 2002 and 2020 were enrolled in a retrospective review. The differences in the baseline demographics and clinical characteristics between ThMG and non-Th MG patients were studied. We compared the time-weighted averages (TWAs) of daily required dosages of pyridostigmine, prednisolone or azathioprine to efficiently maintain daily living activities and earnings between the MG patient groups during 5 consecutive years following thymectomy. Post-thymectomy clinical status, exacerbations or crises were followed. Descriptive statistics were used for analysis with statistical significance set at p < 0.05. (3) Results: ThMG patients had significantly older ages of onset and shorter times from the MG diagnosis to thymectomy. Male gender was the only significant factor associated with ThMG. TWAs of the daily MG treatment drug dosages required showed no differences between the groups. Additionally, the rates of exacerbations and crises were not different, but decremental trends were shown in both groups after the thymectomies. (4) Conclusions: The daily dosage requirements of MG treatment drugs were not different. There was a trend of decreasing adverse event rates despite no statistically significant differences during the first 5 years after thymectomy in ThMG and non-ThMG patients.