Myasthenia Gravis Associated with Thymoma – a Cohort of Patients in the Slovak Republic (1978–2015)

Czech version

Authors: I. Martinka ¹; M. Fulová ²; M. Schnorrer ³; F. Cibulčík ¹; P. Špalek ¹
Authors‘ workplace: Centrum pre neuromuskulárne ochorenia, Neurologická klinika SZU a UN Bratislava ¹; Epidemiologický ústav, LF UK, Bratislava ²; III. chirurgická klinika LF UK a UN Milosrdní bratia, Bratislava ³
Published in: Cesk Slov Neurol N 2016; 79/112(5): 552-559
Category: Original Paper

Overview

Introduction:
Thymoma-associated myasthenia gravis (TAMG) differs from other forms of MG mainly by combined presence of intrathymic (thymus, thymoma) and extrathymic autoimmune mechanisms in their immunopathogenesis.

Aims:
We present a retrospective longitudinal study of 123 patients with TAMG registered in the Slovak Centre for Neuromuscular Diseases between 1978 and 2015. The aim of the study was to analyse epidemiological and clinical data, laboratory findings and factors affecting prognosis of TAMG.

Material and methods:
We analysed data from medical records of patients with TAMG. We examined the age at disease onset, gender, presence of autoantibodies against AChRs and MuSK and type of clinical symptomatology. We evaluated therapies used, clinical status at the last examination and prognosis of TAMG patients.

Results:
Out of 2,074 MG patients, we found TAMG in 123 patients (5.9%), 46 men and 77 women. Median age at disease onset was 51 years. All patients, except one, had AChR seropositive MG. In 78 patients (63.4%) remission or significant improvement by immunotherapy and surgical treatment was achieved. The best results were obtained in patients with early TAMG diagnosis. MG has not been the primary cause of death in any patient for the last 20 years. 91 patients had benign and 32 malignant thymoma. Six patients with malignant thymoma died following thymoma dissemination, four of these had MG in remission.

Conclusion:
TAMG was found in 5.9 % of 2,074 patients. TAMG is AChR-seropositive. Both, MG severity and biological characteristics of thymoma, determine TAMG prognosis. Early diagnosis and optimal treatment of TAMG are crucial for favourable prognosis.

Key words:
myasthenia gravis – thymoma – immunopathogenesis – diagnosis – treatment – prognosis

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.

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