Juvenile myasthenia gravis

Abstract

Juvenile myasthenia gravis shares a similar pathophysiologic origin with adult myasthenia gravis, but there are important differences, mostly relating to epidemiology, presentation, and therapeutic decision making. Gender ratios and the proportion of seropositive patients differ in the pre- and postpubertal age groups. The diagnostic evaluation is similar to that in adults, although special techniques are sometimes necessary to perform single-fiber electromyography in younger patients. Therapeutic decisions in affected children and adolescents are complicated by the greater long-term consequences of using steroids, and thus other interventions, such as intravenous immunoglobulin (IVIg) and plasmapheresis, may play a greater therapeutic role in this population than in adults. Steroid-sparing agents may contribute to the management of refractory cases, but they should be used with caution due to the risk of malignancy.

The characteristics of juvenile myasthenia gravis among South Africans

“…Racial variation among juveniles with MG has been previously reported, with a very high incidence of ocular MG among Asian children. 6 Interestingly, we show that children with African genetic ancestry, as opposed to European ancestry, also show a trend toward more ocular MG, with an age peak between 2 and 4 years. 3 Moreover, we show that a substantial proportion of children with generalised AChR antibody-positive MG develop severe, treatmentresistant ophthalmoplegia associated with significant morbidity (Fig.…”

“…The MGFA grades at presentation and frequency of AChR-positive generalised MG among this cohort were similar to other juvenile cohorts. 3,6,10 Remission rates in children are generally said to be high (11 -37%). 2,6,7,10 Our overall remission rate of 45%, of whom approximately 10% went into spontaneous remission, is comparable.…”

“…3,6,10 Remission rates in children are generally said to be high (11 -37%). 2,6,7,10 Our overall remission rate of 45%, of whom approximately 10% went into spontaneous remission, is comparable. Compared with generalised disease, ocular MG showed more frequent remissions and more often without the use of immunosuppressive therapies.…”

An Increase in Circulating B Cell–Activating Factor in Childhood-Onset Ocular Myasthenia Gravis

“…The presence of thymoma is exceedingly rare in pediatric populations. Pediatric MG also spontaneously resolves at a higher rate than 12,[15][16][17][18][19] Nevertheless, immunological differences between childhood-onset and adult MG remain unclear.…”

“…Patients were diagnosed with ocular MG by pediatric neurologists on the basis of: (1) the presence of fluctuating ocular muscle weakness with fatigability; (2) normal strength in all other muscles; (3) positive response to an anti-cholinesterase injection; and (4) absence of abnormal electrophysiological signs such as a decrement of more than 10% in compound muscle action potential on repetitive nerve stimulationof the trapezius muscle (to exclude generalized MG). 12,13 The mean age AE standard deviation (SD) of MG patients was 5.9 AE 4.4 years (range, 1.8-13.0 years) and 7.8 AE 4.5 years (range, 1.1-12.8 years) in the controls. Samples were obtained from nine patients with ocular MG who received no immunosuppressive therapy (IST; the pre-IST MG group).…”