Myasthénies oculaires : diagnostic et traitement

[Introduction of an anticholinesterase drug in the context of myasthenia, in a severe asthmatic patient]

Association of asthma with myasthenia gravis presents a twofold peculiarity. First, as dyspnea characterizes both conditions, diagnostic orientation is difficult. Second, from a therapeutic standpoint, the initiation of anticholinesterase treatment requires a multidisciplinary approach due to possible contraindication for asthma. We report on the case of a patient monitored for severe asthma and treated with biotherapy, and also monitored for myasthenia gravis, and treated with anticholinesterase.

Prognostic factors and health-related quality of life in ocular Myasthenia Gravis (OMG)

We evaluate the factors predictive of prognosis in 91 Caucasian patients affected by ocular myasthenia gravis (OMG), followed at our Institution during an observational time, ranging from 12 to 240 months. The Myasthenia Gravis Foundation of America (MGFA) clinical classification was used to grade the disease severity. We considered as outcome measures the variation in two subscores, ocular (O-QMG) and nonocular (NO-QMG); the last one reflected bulbar, neck, extremity functions. None of the independent variables evaluated for association with the outcome, as age of onset, type of therapy, length of interval between first and last examinations, and presence of antibodies to acetylcholine receptors (AChR-Abs) significantly affected the evolution of O-QMG and of NO-QMG. Health-related quality of life (HRQol) was assessed in 63 patients. Variations of diplopia or ptosis did not affect significantly physical (PCS) or mental composite subscores (MCS) of the Short-Form Health Survey (SF-36). Human leukocyte antigen (HLA) genotyping was studied to explore whether HLA class I and II allelic distribution differed among MG patients and controls. None of the studied HLA alleles significantly differed between OMG patients and controls. Similarly, none of the alleles with frequencies higher than 15% either in OMG patients or in controls was significantly associated, after Bonferroni correction, with the presence or absence of anti-AChR-Abs in serum.

Presumed isotretinoin-induced, concomitant autoimmune thyroid disease and ocular myasthenia gravis: a case report

Introduction

There are many adverse effects that have been described for isotretinoin. To the best of our knowledge, this is the first report of a possible association of oral isotretinoin intake with autoimmune thyroiditis and ocular myasthenia gravis (OMG).

Case Presentation

A 19-year-old Caucasian male, who had used oral isotretinoin for severe acne disease for the previous six months, was referred to our clinic. He had a three-week history of diplopia and variable bilateral ptosis. Physical examination showed moderate periorbital edema and limitations of up- and down-gaze in the left eye. Laboratory findings and thyroid ultrasound were consistent with autoimmune thyroiditis. Antithyroid therapy did not relieve the clinical symptoms. Concomitant OMG was suspected. Variable ptosis and a positive response to oral prednisolone of 40 mg/day and pyridostigmine of 360 mg/day supported the diagnosis of concomitant autoimmune thyroiditis and OMG.

Conclusion

Autoimmune disorders may be triggered by oral isotretinoin treatment. Clinicians prescribing isotretinoin should be aware of the possible association between isotretinoin intake and concomitant autoimmune thyroiditis and OMG.