A Comprehensive Approach to Myasthenia Gravis With Thymoma: A Case Report Highlighting Management of Myasthenic Crisis and Post‐Crisis Care

ABSTRACT

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder that leads to muscle weakness and rapid fatigue, often exacerbated by thymoma, a tumor of the thymus gland. This case report presents the clinical management of a 40‐year‐old female with MG complicated by thymoma, who presented with a severe myasthenic crisis. The patient required intensive care, including respiratory support, plasmapheresis, and immunosuppressive therapy. Initial evaluations confirmed the diagnosis of MG through the detection of high levels of anti‐acetylcholine receptor antibodies, and a CT scan revealed a thymic mass, indicative of thymoma. The management strategy included acetylcholinesterase inhibitors, immunosuppressive agents, and supportive therapies to stabilize the patient. The patient responded positively to plasmapheresis, which significantly improved her condition. Follow‐up CT imaging confirmed the presence of thymoma, reinforcing the need for further investigation into surgical interventions such as thymectomy. The report also emphasizes the critical role of a multidisciplinary approach in managing MG with thymoma, underscoring the importance of early diagnosis and timely intervention to prevent recurrent crises. Additionally, it discusses the evolving role of thymectomy in MG patients with thymoma and the potential of newer treatments, such as complement inhibitors, for refractory cases. This case highlights the complexities of managing MG complicated by thymoma and stresses the importance of ongoing research into therapeutic strategies. Early diagnosis, effective management, and continuous monitoring remain essential to optimizing outcomes for patients with these complex conditions.

Summary.

• Early diagnosis and multidisciplinary management of myasthenia gravis with thymoma, including plasmapheresis and immunosuppressive therapy, is critical for stabilizing myasthenic crisis and preventing recurrence. Timely intervention and ongoing monitoring optimize outcomes in this complex condition, highlighting the importance of integrated care.

• This case highlights the complexities of managing MG complicated by thymoma and stresses the importance of ongoing research into therapeutic strategies.

1. Introduction

Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder characterized by skeletal muscle weakness and rapid muscle fatigue. This condition arises from an antibody‐mediated blockade of neuromuscular transmission, leading to impaired communication between nerves and muscles. The hallmark of MG is muscle weakness that worsens with activity and improves with rest [1, 2]. The incidence of MG ranges from 4.1 to 30 cases per million person‐years, with a prevalence of 150–200 cases per million. Thymoma, a tumor originating from the thymus gland, is found in approximately 10%–20% of MG patients, while MG is present in 30%–50% of patients with thymoma [3]. This association suggests a significant interplay between these two conditions. The pathogenesis of MG involves the production of autoantibodies against acetylcholine receptors (AChRs) at the neuromuscular junction, leading to impaired neuromuscular transmission. In patients with thymoma, the thymus gland's role in T‐cell development may contribute to the production of these autoantibodies, thereby linking thymic pathology with MG [4, 5].

Patients with MG commonly present with ptosis, diplopia, and generalized muscle weakness. In severe cases, such as myasthenic crisis, respiratory muscles are affected, leading to respiratory distress and the potential need for mechanical ventilation. Diagnosis of MG involves clinical evaluation, electrodiagnostic studies, and serological tests for AChR antibodies. Thymoma is often identified incidentally during imaging studies conducted for MG evaluation. CT scans typically reveal a soft tissue mass in the anterior mediastinum, which may show mild heterogeneous enhancement post‐contrast, indicative of thymoma [1, 2, 4]. Management strategies for MG include acetylcholinesterase inhibitors, immunosuppressive therapies, plasmapheresis, and thymectomy. Thymectomy, the surgical removal of the thymus gland, is recommended for patients with MG and thymoma, as it may alleviate symptoms and improve disease outcomes. However, the role of thymectomy in MG patients without thymoma remains under investigation [5, 6]. The prognosis for patients with MG has improved with advancements in medical and surgical treatments. Early diagnosis and appropriate management are crucial in reducing morbidity and enhancing quality of life. The presence of thymoma in MG patients may influence disease severity and response to treatment [7, 8]. The interplay between MG and thymoma underscores the importance of a comprehensive diagnostic approach and individualized treatment plans [8, 9, 10]. Understanding the epidemiology, pathophysiology, and management options for these conditions is essential for healthcare providers to deliver optimal care. Ongoing research continues to shed light on the complex relationship between thymic pathology and autoimmune neuromuscular disorders.

This case report adds valuable insights into the clinical management of a patient with myasthenia gravis and thymoma, highlighting the challenges of diagnosing and treating myasthenic crisis in the presence of thymic pathology. By presenting a comprehensive diagnostic approach, including imaging studies and immunological testing, this report emphasizes the significance of timely interventions such as plasmapheresis and immunosuppressive therapy in stabilizing patients. Furthermore, it underscores the critical role of multidisciplinary care in managing complex cases of MG, particularly those with concomitant thymoma, contributing to the ongoing discourse in the field.

2. Case History/Examination

A 40‐year‐old female patient with a previous diagnosis of myasthenia gravis (MG) was admitted to the tertiary medical center on January 07, 2025 with complaints of severe respiratory distress, difficulty swallowing, blurred vision, generalized muscle weakness, dysphonia (hoarseness of voice), difficulty speaking, and loose stools. Initial vital signs included a pulse rate of 92 beats per minute, blood pressure of 130/80 mmHg, respiratory rate of 28 breaths per minute, and oxygen saturation of 88% on room air. A chest x‐ray performed at the referring hospital showed no evidence of pneumonia or other acute cardiopulmonary abnormalities, but the clinical presentation raised suspicion for a neuromuscular disorder. Upon initial evaluation, her condition was deemed critical, as she exhibited significant respiratory distress but remained conscious, with a Glasgow Coma Scale (GCS) score of 15/15. The diagnosis of MG exacerbation was suspected based on her history and clinical presentation, including characteristic symptoms of muscle weakness worsening with activity, but other differentials such as stroke, Guillain‐Barré syndrome, or botulism were considered. To rule out these alternatives, a neurological examination was performed, revealing no focal deficits, and an initial brain CT scan was normal, excluding acute central nervous system pathology. The patient was promptly transferred to the intensive care unit (ICU) for close monitoring and respiratory support, which included noninvasive ventilation (BiPAP) initially, with readiness for intubation if her condition deteriorated. Despite presenting with these alarming symptoms, the history provided did not immediately suggest a definitive diagnosis, which posed a challenge for the medical team.

3. Differential Diagnosis, Investigations and Treatment

Initial laboratory investigations conducted at the referring hospital revealed a normal white blood cell count of 10,000/mm³, which suggested no significant infection‐related abnormalities, although there was some indication of a potential underlying infection. A urine culture revealed the presence of Klebsiella species, resistant to levofloxacin, raising concerns about a bacterial infection contributing to her symptoms. Biochemical analysis showed a serum creatinine level of 0.67 mg/dL, low calcium at 2.22 mg/dL, albumin at 3.19 g/dL, and a hemoglobin level of 10.6 g/dL. While these findings were abnormal, they did not provide conclusive evidence to explain her severe respiratory symptoms.

Given the severity of her presentation and the potential for an acute neuromuscular disorder, the clinical team suspected an acute myasthenic crisis and promptly initiated the acetylcholinesterase inhibitor pyridostigmine to manage the potential neuromuscular blockade. Concurrently, intravenous meropenem was administered to address the Klebsiella urinary tract infection. As her condition continued to deteriorate, the decision was made to proceed with four cycles of plasmapheresis, a therapeutic modality aimed at removing harmful immune mediators circulating in the patient's system.

Over the following days, the patient demonstrated significant improvement and was eventually stable enough to be discharged from the ICU on January 30, 2025. The plasmapheresis treatment was extended over several days, and additional immunosuppressive therapy with mycophenolate mofetil and prednisolone was introduced to mitigate the autoimmune component of myasthenia gravis. During her ICU stay, the patient was also prescribed oral calcium supplements, antihypertensive olmesartan, pantoprazole for gastrointestinal protection, and antihistamines to manage any allergic reactions. Nebulization therapy with Ipratropium and salbutamol was recommended for ongoing respiratory support during her recovery at home.

Although the patient was discharged in stable condition, the medical team recognized the importance of a thorough follow‐up to ensure continued recovery and to investigate the underlying etiology of her initial crisis. On March 08, 2025, the patient returned to the tertiary medical center for a follow‐up visit at the Department of Medicine. During this visit, the patient reported significant improvements in her condition, including better control of her respiratory symptoms and no further issues with swallowing. Her vital signs were stable, with a pulse rate of 84 beats per minute, blood pressure of 110/70 mmHg, and oxygen saturation at 98% on room air. Neurological examination revealed no abnormalities, and cranial nerve function appeared intact. However, the medical team determined that further investigations were necessary to rule out any ongoing concerns that could potentially precipitate another myasthenic crisis.

A comprehensive diagnostic workup was undertaken, which included a CT scan of the chest with contrast. The scan revealed a soft tissue mass in the anterior mediastinum (Figures 1, 2, 3), measuring approximately 3.6 cm (CC) × 3.0 cm (AP) × 4.2 cm (TR). The lesion was located between the aorta and pulmonary artery. The normal triangular morphology of the thymus was not visible, and post‐contrast imaging showed mild heterogeneous enhancement of the lesion. This finding was highly suggestive of thymoma, a tumor of the thymus gland commonly associated with myasthenia gravis. Additionally, the CT scan showed that the lung parenchyma on both sides had normal parenchymal attenuation with a normal bronchovascular pattern. The heart appeared normal in size, and the trachea was unremarkable. The esophagus showed normal wall thickness, and no enlarged lymph nodes were noted in the mediastinum. There were no signs of pleural effusion or thickening. The bony thorax revealed no abnormalities, and the visible breast shadows, abdominal structures, and neck were all unremarkable. This was further corroborated by an echocardiography report showing normal cardiac function, with an ejection fraction of 65% and no regional wall motion abnormalities, effectively ruling out cardiovascular causes for her distress. Electrocardiography revealed sinus tachycardia, likely a secondary response to her acute condition. Additionally, the immunological report showed a positive result for anti‐acetylcholine receptor antibody at 8.30 nmol/L, which is above the threshold of 0.45 nmol/L for a positive result. This high level of antibody is indicative of autoimmune myasthenia gravis (MG), further confirming the diagnosis of MG and supporting the clinical findings. This result has a clinical specificity of 100% and a clinical sensitivity of 92%, making it a reliable indicator for MG in the context of the patient's presentation.

FIGURE 1.

The axial CT scan of the chest images show a soft tissue mass in the anterior mediastinum, which is highly suggestive of thymoma (yellow arrow). The mass is located between the aorta and pulmonary artery and appears irregular in shape. It measures approximately 3.6 cm (CC) × 4.2 cm (TR), matching the previously described dimensions of thymoma. Post‐contrast images reveal mild heterogeneous enhancement, which is typical for a thymoma, indicating mixed components in the tumor, such as areas of necrosis, cystic changes, or varying vascularity. The normal triangular morphology of the thymus is not visible, as the mass is displacing it, further supporting the diagnosis. The images also show normal lung parenchyma on both sides, with no abnormalities in the lung fields. The heart appears normal in size, and there are no enlarged lymph nodes in the mediastinum, which is consistent with a benign thymoma. Additionally, there is no evidence of pleural effusion, pleural thickening, or any abnormalities in the bony thorax. These findings point to a thymoma, a tumor of the thymus gland, often associated with myasthenia gravis, as seen in this patient.

FIGURE 2.

The axial CT scan images show a soft tissue mass in the anterior mediastinum, which is highly suggestive of thymoma, indicated by the yellow arrows. The mass is situated between the aorta and pulmonary artery and appears irregular in shape.

FIGURE 3.

The coronal CT scan images show a soft tissue mass in the anterior mediastinum, indicated by the yellow arrows.

Despite the improvement in her symptoms during this follow‐up visit, further biochemical analysis confirmed that the patient's liver and renal function remained stable, with serum creatinine at 0.72 mg/dL, serum calcium at 9.3 mg/dL, and albumin at 4.9 g/dL. Immunological testing revealed normal thyroid function, with serum F‐T4 at 1.1 ng/dL, F‐T3 at 3.05 ng/dL, and TSH at 3.11 μIU/mL. Blood screening tests for anti‐HCV, anti‐HIV, and HBsAg were nonreactive, effectively ruling out other infectious causes.

4. Results (Outcome and Follow‐Up)

With the diagnosis of myasthenia gravis now confirmed and the finding of thymoma on CT imaging, the patient's management plan was adjusted accordingly. She was continued on her prior medication regimen, which included pyridostigmine, mycophenolate mofetil, prednisolone, olmesartan, pantoprazole, and calcium supplements. Laboratory tests conducted post‐admission revealed a hemoglobin level of 11 g/dL, a white blood cell count of 12,290/mm³ (with 92% neutrophils), and a platelet count of 379,000/mm³. Biochemical tests showed slight fluctuations in serum creatinine (0.73 mg/dL), ALT (36 U/L), and serum calcium (9.1 mg/dL), but electrolytes remained stable.

Following the completion of her investigations and with her clinical condition now more stable, the patient was referred to the Transfusion Medicine Department for further management of her myasthenia gravis. The department recommended two to three sessions of therapeutic plasma exchange (TPE), along with additional relevant investigations to assess the need for potential surgical intervention for the thymoma. Throughout this process, the multidisciplinary team carefully monitored the patient's condition to prevent the recurrence of the myasthenic crisis.

5. Discussion

This case report presents the clinical journey of a 40‐year‐old female diagnosed with myasthenia gravis (MG) complicated by thymoma, who experienced a myasthenic crisis (MC) requiring intensive management. This case highlights the complexities of diagnosing and managing MG, particularly when complicated by thymoma, a neoplasm that frequently coexists with MG. The interplay between MG and thymoma is well documented, as thymoma is present in approximately 10%–20% of MG patients, while MG occurs in 30%–50% of thymoma cases [3, 4]. Here, we compare and contrast our findings with existing literature, provide logical explanations for our clinical outcomes, and discuss potential implications of the case.

The patient's acute presentation with respiratory distress, dysphagia, dysphonia, and generalized muscle weakness mirrors the typical symptoms of a myasthenic crisis. As shown in the study by Rahman et al. [3], myasthenic crises often require rapid intervention, including respiratory support, as respiratory muscles become significantly weakened. Between 66% and 90% of patients with MG may require intubation during a crisis [3]. In this case, the early use of acetylcholinesterase inhibitors like pyridostigmine, aimed at enhancing neuromuscular transmission, was appropriate and consistent with treatment protocols [1, 11]. Additionally, the patient was diagnosed with a Klebsiella urinary tract infection, and meropenem was administered, reflecting the need to address concurrent infections that may exacerbate MG symptoms.

The administration of plasmapheresis, which was employed due to its effectiveness in removing circulating autoantibodies during a crisis, is supported by current research [7, 12]. Plasmapheresis, as a first‐line intervention for acute exacerbations, aids in stabilizing patients by reducing the pathogenic antibody burden [12]. In line with the literature, this patient's condition significantly improved following plasmapheresis, underscoring its importance in critical management.

The follow‐up CT scan that revealed a soft tissue mass in the anterior mediastinum, highly suggestive of thymoma, is a critical diagnostic step. Thymoma is often discovered incidentally during MG evaluation, and its diagnosis is typically confirmed through imaging techniques such as CT scans, as noted by Cata et al. [11]. Our findings are consistent with the literature, where thymomas are reported in 10%–20% of MG patients, such as Mao et al. [10]; Cacho‐Díaz et al. [13]. The mass's characteristics, including its location and heterogeneous enhancement post‐contrast, align with established imaging criteria for thymomas [11]. Notably, the absence of visible thymic tissue is often a distinguishing feature of thymomas, and in this patient's case, the imaging findings corroborated the diagnosis.

Moreover, the presence of anti‐acetylcholine receptor antibodies, found in high levels in this patient, is another diagnostic hallmark of MG, confirming the autoimmune origin of her symptoms [7, 14]. The clinical sensitivity and specificity of anti‐AChR antibodies in diagnosing MG in the context of thymoma are well established, with the level found in our patient above the diagnostic threshold [12]. This immunological confirmation supports the diagnosis of MG and provides a clear path for management.

In the management of MG with thymoma, a multidisciplinary approach remains key. In this case, the combination of plasmapheresis, immunosuppressive therapy, and careful monitoring was essential for stabilizing the patient and preventing further crises. Mycophenolate mofetil and prednisolone, as immunosuppressive agents, were added to reduce the production of autoantibodies, aligning with standard treatment protocols [12, 15, 16]. The introduction of these therapies reflects the current understanding that immunosuppression is crucial for controlling the autoimmune component of MG. Calcium supplementation, which was introduced to address the patient's hypocalcemia, is consistent with current MG management guidelines, as hypocalcemia can exacerbate neuromuscular irritability, leading to worsened symptoms [15]. These interventions were pivotal in the patient's recovery, emphasizing the need for a holistic approach that addresses both the autoimmune disease and supportive care needs.

The decision regarding thymectomy in this patient's case requires careful consideration. While the role of thymectomy in MG patients with thymoma is well supported, with studies indicating that it can lead to significant improvements or even complete remission in some patients described by Mao et al. [10] and Cacho‐Díaz et al. [13], the timing and necessity for surgery remain contentious. Some studies suggest that thymectomy is particularly beneficial for patients with thymoma who have severe, refractory MG, while others indicate that the role of thymectomy in patients without thymoma remains an area for further investigation [10, 13, 17]. Given the current state of the patient's condition, it was deemed appropriate to initiate supportive therapies before considering thymectomy.

6. Recent Advances and Guidelines

The 2021 international consensus update for MG management reinforces the importance of a personalized, multidisciplinary approach, including the use of acetylcholinesterase inhibitors, plasmapheresis, immunosuppressive therapies, and thymectomy [15]. The use of newer agents, such as complement inhibitors like eculizumab, is also gaining traction, particularly for refractory MG cases. Although these therapies show promise, their long‐term efficacy in thymoma‐associated MG remains a topic of ongoing research [9, 18, 19].

In light of these advances, it is crucial to note that while the treatment options for MG have expanded significantly, thymectomy remains an essential element in the management of MG complicated by thymoma. However, its role and the precise timing of surgery require further clarification through randomized controlled trials [12, 15].

7. Conclusion

This case underscores the critical importance of a thorough diagnostic workup and a multidisciplinary approach in managing complex medical conditions. Initially presenting with a constellation of symptoms suggestive of various potential diagnoses, the patient's condition was ultimately attributed to a combination of myasthenia gravis complicated by thymoma. The management strategy, which included plasmapheresis, antibiotics, immunosuppressive therapy, and vigilant follow‐up, played a pivotal role in stabilizing the patient and preventing further crises. This case highlights the importance of early diagnosis, aggressive intervention, and continuous monitoring in ensuring optimal outcomes for patients with multifaceted autoimmune and oncological conditions.

Author Contributions

Sakib Abrar: conceptualization, formal analysis, investigation, project administration, resources, supervision, validation, visualization, writing – original draft. Shah Tanvir Ahmed: conceptualization, data curation, writing – original draft, writing – review and editing. Ibrahim Khalil: conceptualization, data curation, formal analysis, methodology, project administration, validation, writing – original draft, writing – review and editing. Md. Imran Hossain: writing – original draft, writing – review and editing.

Consent

Written informed consent was obtained from the patient to publish this report in accordance with the journal's patient consent policy.

Conflicts of Interest

The authors declare no conflicts of interest.

Abrar S., Ahmed S. T., Khalil I., and Hossain M. I., “A Comprehensive Approach to Myasthenia Gravis With Thymoma: A Case Report Highlighting Management of Myasthenic Crisis and Post‐Crisis Care,” Clinical Case Reports 13, no. 10 (2025): e71063, 10.1002/ccr3.71063.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.