What are the symptoms?

The symptoms of multiple sclerosis really depend on which areas of the brain have lost their myelin. It can cause any of the following symptoms:

1. Sensory symptoms- this can be numbness (or lack of sensation), tingling, pins and needles or pain. It tends to involve one side of the body as in the face, arm and leg although if the area of myelin loss is in the spinal cord it may cause sensory symptoms in both legs.
2. Weakness- One of the common ways that multiple sclerosis causes weakness is called a “spastic paraparesis”. Spasticity is a feeling of stiffness. Paraparesis means weakness of both legs. The nerve pathways that connect your brain, spinal cord and muscles work together to produce smooth coordinated movement. When these nerve pathways are disrupted it can lead to an overactivity of some muscles and underactivity of others which translates in to stiff and weak muscles that don’t work properly.
3. Walking and balance problems- Walking or gait disturbance is one of the most common symptoms in multiple sclerosis. There are several factors that contribute to your ability to walk properly- this includes the strength of your muscles, the tone of your muscles, balance centres in the brain and sensation or the ability to feel where your feet are. In multiple sclerosis any or all of these can be affected and this translates in to difficulty walking and poor balance.
4. Tremor- some patients with multiple sclerosis experience tremor or uncontrollable shaking. The tremor occurs when the area of myelin loss is where there are nerve pathways involved in the smooth coordination of movement. This is not a particularly common symptom of multiple sclerosis.
5. Visual symptoms- when the loss of myelin is from the optic nerve there may be loss of vision in one eye. What happens is the vision progressively decreases over a period of a few days to almost complete loss of vision. This is called “optic neuritis” (which essentially means inflammation of the optic nerve) and is actually quite a common symptom of multiple sclerosis. Sometimes eye movements can be painful with this.                                                                                 Sometimes when vision is involved in multiple sclerosis the symptom is that of double vision. With both eyes open you may see two images- usually they are side by side. Closing either eye restores vision to seeing just one image- the problem is that the eyes opened together are seeing two different images- the problem is the eyes no longer work together to form one image.
6. Bladder dysfunction- multiple sclerosis lesions can block or delay transmission of nerve signals in areas of the central nervous system that control the bladder and urinary sphincters. This can lead to the bladder becoming either overactive which leads to symptoms of frequency of urination including night time urination. It can lead also to incontinence (the inability to hold urine before reaching the bathroom). The other thing that can happen is that the bladder may not empty properly. If this occurs there is a higher chance of developing frequent urinary tract infections.

The symptoms listed above are often how multiple sclerosis presents. It may be with one or more of the above (although usually with just one of the symptoms listed above).

Uhthoffs phenomenon- This can occur in patients with multiple sclerosis. It refers to the temporary exacerbation of multiple sclerosis symptoms that occurs in some patients with exposure to heat or humidity. It was originally described in relation to optic nerve symptoms such that vision may get worse with heat however it can really apply to all symptoms of multiple sclerosis. Not every patient will experience this. It is important to note that it does not signify worsening of disease or a more severe immune attack on the myelin. It simply reflects the fact that nerves can be heat sensitive and this is exacerbated when nerves are damaged. Once the heat is eliminated the symptoms should return to how they were.

There are several other symptoms that are considered non-specific (they can occur with multiple other conditions) that are quite common in patients with multiple sclerosis. These include:

1. Pain- Pain in multiple sclerosis may arise for a number of reasons. Firstly, if the sensory nerves are involved this alone can lead to pain. This would have the characteristic of a burning or nerve related pain. It can be intermittent in nature or constant. It usually responds well to nerve pain killers as described in the neuropathy section. Another cause of pain in multiple sclerosis relates to muscle stiffness and spasticity. When the muscles are tight this can cause pain. In this instance treating muscle spasticity is more likely to give relief than nerve pain killers. Whichever is contributing or causing your pain will become apparent when your neurologist has gone through the history and examination.
2. Fatigue- This is a very prominent symptom in multiple sclerosis. It can have many different causes.  It can be part of the multiple sclerosis itself. When this is the case it is termed lassitude. Patients who experience this form of fatigue may find even the most simple of daily tasks extremely tedious and tiring. It is not known exactly what the underlying cause of this fatigue is. It is not correlated with the severity of the underlying disease. However, when evaluating fatigue in multiple sclerosis it is important to look at other potential contributors. For example, patients with multiple sclerosis who have bladder symptoms or painful spasms may not be able to sleep through the night. Broken sleep is definitely a contributor to fatigue in these cases. Similarly, having a chronic illness such as multiple sclerosis can lead to depression and fatigue is a very common symptom in patients who have depression. It would be worth checking also for anaemia and low thyroid function as both of these are common treatable causes of fatigue.
3. Cognitive problems- Multiple sclerosis can affect cognition. Cognition encompasses all of our higher functions that allow us to interact with the world every day. For example, it includes things like short and long term memory, our ability to process information in a short amount of time as you would do in a normal conversation, our ability to calculate and our ability to plan. For example, if someone asked you what you were doing for the weekend you would have to firstly understand their question, then pull from your memory what you had planned that weekend and then give the information back and this is something that you do so quickly that you barely even consider it as a particular function. It may involve you calculating how much time you would have to meet them for coffee before you would be going somewhere for the weekend and maybe adjust your plan based on this new arrangement. In multiple sclerosis any or all of these functions can become impaired. In particular, mental processing speed tends to slow down. This can have huge implications for the patient and is a very common reason for having to leave work with a diagnosis of multiple sclerosis.

The neurodegeneration that can occur in the brain of someone with multiple sclerosis is thought to be particularly associated with loss of cognitive functions. Therefore, it tends to occur later in the illness but it has been known to occur early on. This is also where other symptoms such as fatigue and poor sleep can have an effect. If you are excessively fatigued or are having trouble sleeping then any issue with cognitive function will almost certainly become worse. This again brings us back to the thorough history and examination that your neurologist will perform. It is of paramount importance to establish any or all of the symptoms that you are experiencing because improving things like sleep can have a very positive impact on cognition. Similarly if pain is one of your main complaints with multiple sclerosis it will also have a negative impact upon your cognition.

1. Lhermittes sign- this occurs commonly in multiple sclerosis but is not specific to this disease. It is an electric-shock like sensation that occurs on bending the neck forward. The sensation can travel down the spine, in to the arms and legs and sometimes the trunk. It is momentary. Some people experience this as pain and some as just an unusual sensation. It tends to last no longer than just a few seconds. It is thought to relate to a mis-communication between the nerves that have lost their myelin.