(Disseminated Sclerosis, MS)
MULTIPLE SCLEROSIS is the commonest demyelinating disease.
The exact cause in unknown. Possibly the nature of the disease is one of genetic susceptibility (HLA linkage, HLA-DRZ) or viral infection or allergy as a result of metabolic upset or deficiency. It is common in temperate climate. Excessive consumption of animal fat has been blamed for its development.
Demyelination occurs in different places focally and at different phases of the disease in the white matter of the central nervous system giving rise to “plaques” which ultimately form scars. The following areas of the CNS may show these lesions:
(i) Cervical spinal cord.
(ii) Brain stem with cerebellum.
(iii) Periventricular region.
(iv) Optic nerves.
Trauma, infection, operation, emotional upsets, fatigue, pregnancy etc.
Onset is gradual
Age: 15 to 50 years.
Unilateral retrobulbar neuritis is an early feature giving rise to pain during movement of the eyes and dimness of vision. Double vision, nystagmus, swelling of the optic disc, temporal pallor etc. are also seen. These may regress and reappear.
These include hemiplegia, monoplegia, paraplegia, tetraplegia paresis, intention tremor, scanning speech, dysarthria, pseudobulbar pasly etc.
Tingling and numbness, impaired postural sense giving rise to So-called “useless hand syndrome” and impaired vibration sense may develop. Sometimes flexion of neck may produce electric shock like sensation on the back and limbs which though not diagnostic but highly suggestive of this condition (Lhermitte’s sign).
Abdominal reflexes are lost early in the disease. Plantar reflex becomes extensor. Regarding sphincteric reflexes there may be precipitancy in micturition in early stage, and sometimes incontinence of urine and faeces.
It shows euphoria which is characteristic. Emotional upsets, delusions and finally dementia may develop. Many patients may have depression.
These include fever and fatigue.
Trigeminal neuralgia, tonic spasms with dysarthria, ataxia, etc. may be seen.
In the early stages there may be complete remission of all these features lasting for many years but may reappear once again. Recurrence and remission are very characteristic features of this disease.
In advanced cases the characteristic features are seen, e.g., nystagmus, intention tremor and scanning speech which are together known as Charcot’s triad.
Clinically there may be spinal, brain stem, cerebral and cerebellar forms. In the first type spastic ataxic paraplegia, in the 2nd type different oculomotor palsies, in the 3rd variety psychic and emotional disturbances with hemiplegia while in cerebellar form cerebellar syndrome may develop.
According to the progress of the disease clinically three forms are recognised:
1. Relapsing remitting disease
In majority of the cases after initial development of clinical features months or years are passed before either new symptoms develop or original ones are recurred.
2. Secondary progressive disease
In some cases the course of the disease steadily goes downhill which may not have link with acute relapses.
3. Primary progressive disease
In few cases from the initial development of features there is steady progression till the patient becomes completely incapacitated.
The CSF shows a paretic type of Lange’s colloidal gold curve in presence of negative VDRL. The protein level is normal but the gamma globulin fraction may be increased. Oligoclonal bands of IgG is present. CT scan may show plaques here and there in the CNS seen as hypodense areas. MRI scanning is very valuable because it easily detects plaques. EEG is usually normal. Visual evoked responses (VER) may be delayed due optic neuropathy.
There is no specific treatment. For relief of pain and spasticity of muscles Baclofen (a derivative of GABA) 60-80 mg in divided doses or Carbamazepine may be used. For bladder symptoms, Belladonna preparation and for mental upsets Diazepam may be used. ACTH or Corticosteroids may be of help.
Physiotherapy may also be helpful. If there is focal infection it should be controlled. Spinal cord stimulation by insertion of electrodes in the epidural space is said to be beneficial. Cytotoxic agents (Azathioprine, Cyclophosphamide etc) have also been used. Gluten free diet,polyunsaturated fatty acid in the diet are also probably helpful. Beta interferon is also found to give a good result.