The characteristics of juvenile myasthenia gravis among South Africans
Date
2012-06
Authors
Heckmann, J. M.
Hansen, P.
Van Toorn, R.
Lubbe, E.
Janse Van Rensburg, E.
Wilmshurst, J. M.
Journal Title
Journal ISSN
Volume Title
Publisher
Health and Medical Publishing Group (HMPG)
Abstract
Objectives. To report the characteristics of juvenile-onset (<20
years) myasthenia gravis (MG) in Africa.
Subjects and methods. Six South African centres collected data
which included acetylcholine receptor-antibody (AChR-ab) status,
delay before diagnosis, MG Foundation of America grade at onset,
maximum severity and severity at last visit, therapies, outcomes and
complications.
Results. We report on 190 individuals with a 4-year median
follow-up (interquartile range (IQR) 1 - 8). The median age at
symptom onset was 7 years (IQR 4 - 14). Ocular MG (26%) occurred
among younger children (mean 5.1 years) compared with those
developing generalised MG (74%) (mean 10.2 years) (p=0.0004).
Remissions were obtained in 45% of generalised and 50% of ocular
MG patients, of whom the majority received immunosuppressive
treatment, mainly prednisone. Children with post-pubertal onset
had more severe MG, but deaths were infrequent.
Thymectomies were performed in 43% of those with generalised
MG who suffered greater maximum disease severity (p=0.002);
there was a trend towards more remissions in the thymectomy
group compared with the non-thymectomy group (p=0.057).
There was no racial variation with respect to AChR-ab status,
maximum severity, or use of immunosuppression. However, 23% of
children of African genetic ancestry developed partial or complete
ophthalmoplegia as a complication of generalised MG (p=0.002).
Conclusion. Younger children developed ocular MG and older
children generalised MG. Persistent ophthalmoplegia developing as
a MG complication is not uncommon among juveniles of African
genetic ancestry. A successful approach to the management of this
complication that causes significant morbidity is, as yet, unclear.
Description
The original publication is available at http://www.samj.org.za
Keywords
Myasthemia gravis -- South Africa -- Cross-cultural studies, Opthalmoplegia -- South Africa -- Cross-cultural studies, Myasthemia gravis -- South Africa -- Diagnosis -- Research, Myasthemia gravis -- South Africa -- Treatment -- Research, Ocular myasthemia gravis in children -- South Africa -- Management
Citation
Heckmann, J. M. et al. 2012. The characteristics of juvenile myasthenia gravis among South Africans. South African Medical Journal, 102(6):532-536.