Childhood Myasthenia Gravis(MG)

Posted by e-Medical PPT Thursday, August 23, 2012
Myasthenia Gravis is a neuromuscular disorder that affects skeletal muscles
MG was first described in the year1672
Onset in childhood was recognized by Erb in 1879
MG in childhood comprises 10-20% of all myasthenic patients

Autoimmune MG (Juvenile): (JMG)
Congenital MG (CMG)
Neonatal (transient) MG: 10%

Juvenile Myasthenia Gravis(JMG):
It is Autoimmune
Antibodies directed against AChR in skeletal muscle
Cell and complement mediated process
This leads to a reduced number and function of AChRs
Almost never occurs before 1 year of age.

Fluctuating and fatigable weakness
Symptoms are worse through the day.
Worsening of symptoms may occur after febrile illness or insect bites or certain medications.
Extraocular, bulbar and limb weakness.
Ocular symptoms occur in 90% of cases.
MG remains ocular in only 10-15% of cases (usually with prepubertal onset)
The maximal disease severity is within 2 years of onset.
50% of cases with ocular MG  will become generalized within 2 years and 75% within 4 years.
Bulbar symptoms affect 75% of patients: dysphagia, dysarthria, facial weakness.
Limb weakness (proximal), fluctuating.
Systemic weakness may affect the diaphragm and other muscles of respiration.
Thymoma is rare
Other autoimmune disease are common: diabetes, thyroid dx and JRA.
Spontaneous remission is more common among young patients (up to 30% of cases within 15 years of disease onset in one study)

JMG (diagnosis):
Fluctuating weakness
Positive edrophonium (tensilon) test: negative in 8% of children. Non-specific.
Electrophysiological test is age limited:
RNS:RNS does not discriminate between CMG and JMG.
AChR antibodies
Related Posts Plugin for WordPress, Blogger...

0 Responses to Childhood Myasthenia Gravis(MG)

Post a Comment

Share This


Subscribe by E-mail & receive updates your inbox!
Enter your email address:

Follow Us on Facebook

Blog Archive