Thymectomy, myasthenia gravis

Plasmapheresis is an intermediate form of therapy for myasthenia gravis, having effects that last longer than those of cholinesterase inhibitors but shorter than those of thymectomy. Improvement in myasthenic symptoms often occurs, but its duration is unpredictable. Plasmapheresis usually is reserved for patients who have severe symptoms resistant to other therapeutic approaches or for patients preparing for thymectomy. 

Thymectomy should be offered to those with generalised myasthenia gravis imder 40 years of age, once the cliiucal state allows and unless there are powerful contraindications to surgery. Most cases benefit and about 25% can discontinue drug treatment. Thymectomy should also be undertaken in all myasthenic patients who have a thymoma, but the main reason is to prevent local infiltration for the procedure is less likely to relieve the myasthenia. 

In two patients with thymoma associated with myasthenia gravis, who both had recurrent oral candidiasis after thymectomy, radiotherapy, and chemotherapy levamisole was added as adjunctive therapy in combination with oral nystatin (5). Oral candidiasis responded favorably and substantial relief was obtained, with a concurrent increase in T cells and CD4/CD8 ratio, suggesting restoration of T cell immunity. Adverse effects were not mentioned. 

Myasthenia gravis is a progressive disorder characterized by muscle weakness eye muscles are often the first affected. Research has shown it to be an autoimmune disease in which the victim forms antibodies to his or her nicotinic acetylcholine receptors at motor endplates. It is characterized by fatigability and weakness of the skeletal muscles, especially those of the eyes. Approximately 90% of the patients have droopy eyelids and double vision. Treatments include corticosteroids and thymectomy to reduce the actions of the immune system and anti-ChE agents such as pyridostigmine to improve the effectiveness of the receptors that remain. 

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