Lambert–Eaton Myasthenic syndrome and follicular thymic hyperplasia in systemic lupus erythematosus

Abstract

Fatigue is a prominent feature of systemic lupus erythematosus (SLE), usually ascribed to various factors, such as muscle or joint involvement, anaemia or depression. The Lambert-Eaton myasthenic syndrome (LEMS) is a rare autoantibody-mediated disorder of neuro-muscular transmission. We report on a well-defined LEMS associated with thymus hyperplasia in a SLE patient. An African 41 years-old SLE patient presented with persisting fatigue, myalgia and dyspnea, abolished reflexes and a bilateral ptosis. Neuromuscular electrodiagnostic study showed a clear-cut potentiation that was typical of a pre-synaptic neuromuscular junction disease. Anti-calcium gated channels antibodies were disclosed in serum and a diagnosis of LEMS was made. A total body CT-scan revealed an antero-superior mediastinal mass, compatible with thymoma. The tumour was surgically removed with a final diagnosis of follicular thymic hyperplasia. In conclusion, our observation provides a new example of entangled organ-specific and systemic autoimmunity in the context of thymus pathology. Potentiation study during electromyography should be performed systematically to rule out LEMS in patients with SLE and muscle weakness.

Myasthenia gravis Lambert‐Eaton overlap syndrome

“…The Morimoto et.al. and the Pasqualoni et al patients had LEMS with thymic hyperplasia . The Roohi et al patient represented MG with a positive VGCC‐ab in view of the MG pattern on the RNS test .…”

Systemic lupus erythematosus and thymus persistens: A case report

“…The presence of thymoma is found in 30% of patients with clinically manifested SLE while in 30% of cases it was discovered by accident, radiographically, as it was a case with our patient. The clinical picture of SLE is clearly visible, including all immunoserological activity indicators 5,6,[10][11][12][13] . For the final diagnosis, given the example of our patient, we found that an additional diagnostics was necessary, such as bronchoscopy with TBB and needle biopsy of changes in the mediastinum.…”

“…This was the case with our patient, too. However, the connection between the disorder of thymic function and SLE deserves attention and additional studies, especially when the therapeutic effects of thymectomy are considered 5,8,10,13 .…”

“…This diagnostic reveals thymoma in cytological or histological findings. The association of SLE and thymoma is something which is known these days 4,5 . We report a case of a patient with SLE who was diagnosed the thymus persistens.…”

Lambert-Eaton myasthenic syndrome following H1N1-influenza vaccination - a case report

“…Thymus hyperplasia and thymoma are well‐known entities of MG. Reports of thymic hyperplasia associated with other autoimmune diseases also exist . Thymus plays an important role in T‐cell function on recognizing self‐ vs non‐self‐antigens.…”