Myasthenia gravis: diagnosis and follow-up of 100 consecutive patients

Abstract

One hundred consecutive patients with myasthenia gravis (MG) referred between 1985 and 1989 were analysed for epidemiological characteristics, evolution of early signs, delay in diagnosis, yield of diagnostic tests and effects of treatment. The female to male ratio was 1.6:1.0. Sixteen patients had a thymoma. Ocular MG occurred in 14. Associated autoimmune diseases were found in 15 patients. In 34% of the women and 10% of the men the diagnosis was delayed for more than 2 years. In the first 3 months progression was more rapid in men than in women. Anti-acetylcholine receptor antibodies were found in 94% of the patients with generalized MG and in 29% of the ocular patients. The neostigmine or the edrophonium test was positive in 84% of the generalized and in 60% of the ocular patients. Electromyography was diagnostic in 71% of the generalized and in 42% of the ocular patients tested. Thymectomy was performed in 56 patients (12 with thymomas). Fifty-one per cent were treated with one or more immunosuppressive drugs, at any time. After a mean follow-up of 9.6 years after onset remissions had occurred in 43%, considerable improvement in 25%, moderate improvement in 20% and 12% remained unchanged. There were no deaths due to MG. Thirty-six per cent remained dependent on immunosuppressive drugs. Medication-free remission was most frequent (35%) in the early-onset (< 50 years) group. Side-effects of pyridostigmine were noted in 34% of 99 patients, of prednisone in 65% of 49 patients, and of azathioprine in 54% of 28 patients, but these necessitated stopping the drug in only 1%, 10% and 14% respectively.

Myasthenia gravis and neuromyelitis optica spectrum disorder

“…The clinical features and severity of the diseases in patients with both conditions were compared to those in patients with either disease alone (51 patients with early-onset AChR-MG 23 ; 106 patients with AQP4-NMOSD 24 ); see table e-3. There were no significant differences among these 3 cohorts apart from an increase in other autoimmune manifestations in patients with both diseases compared to the AChR-MG cohort ( p Ͻ 0.0001) and a trend when compared to AQP4-NMOSD alone ( p ϭ 0.0146 [ p Ͻ 0.0026 is significant after Bonferroni correction for multiple comparisons]).…”

Practice parameter: Thymectomy for autoimmune myasthenia gravis (an evidence-based review) [RETIRED]

“…12,17,25,26,29,33 Age and gender. The studies described by Rodriguez et al, 25 Buckingham et al, 27 and Simpson 34 allowed us to determine relative outcome rates in the male MG subgroup.…”

“…Several studies provided sufficient data to recalculate relative rates of outcomes within MG patient subgroups. 12,17,20,21,[25][26][27]29,[32][33][34] Table 4 lists the median change in relative outcome rates within age, gender, and severity subgroups. The positive association between thymectomy and improved outcomes persisted after controlling for each of these variables.…”

Ocular Myasthenia Analysis of Diagnostic and Treatment Options

“…Over seventy-five percent of MG patients initially present with ptosis or diplopia and almost all MG patients experience ocular manifestations sometime during the course of the disease (Beekman et al 1997;Barton and Fouladvand 2000;Daroff and Benatar 2009). About half of patients who present with isolated ocular manifestations develop generalized weakness within six months and up to eighty percent will generalize within 2 years (Bever et al 1983;Oosterhuis 1989;Kupersmith et al 2003).…”

“…Pyridostigmine 30-60 mg three to four times per day are typical starting doses and may be increased to 90 to 120 mg every 3-4 hours per day, if symptoms respond and adverse effects are kept to a minimum. Complications are primarily related to muscarinic effects, in particular abdominal cramps, nausea, vomiting and diarrhea, which occur in at least a third of patients (Beekman et al 1997). Atropine or glycopyrrolate may be used to limit muscarinic activity.…”