Stiff Man Syndrome
STIFF MAN SYNDROME
Stiff Man Syndrome was the name assigned to the condition when first identified in the 1950s by Moersch and Woltman in the USA. In recent years, in the modern world of PC, the condition has also become known as Stiff Person Syndrome. SMS or SPS does not appear to differentiate between sex, colour, or creed, although UK evidence tends to suggest women are more likely to fall victim to SMS.
SMS is a neurological condition believed to be of auto-immune origin. It is unique among neurological diagnoses due to its lack of significant similarity to any other neurological diseases. Although rare, once observed it is quite unforgettable. Because of its rarity, many neurologists and GPs are not aware of the condition. In most cases, the first symptoms are insidious and victims are often initially misdiagnosed with depression. The onset is most frequent between the third and fourth decades of life.
Liz Blows, who set up the UK and Ireland Support Group in 1998, began presenting symptoms in 1990 but it wasn’t until three years later that it became clear something was seriously wrong and she set off in search of a diagnosis which eventually came in 1997. She began the support group with just five members to champion the cause of this little known and misunderstood disease. Today, there are more than 100 members in the group and she remains passionate about raising awareness in both the public and medical sectors.
Her primary role within the group, which has had charitable status since 2003, is responding to phone calls and emails, offering help, guidance and support to anyone who needs it. She is also compiling a list of neurologists who know about SMS to ensure any callers who present with the symptoms can tell their GPs to whom they should be referred. Another on-going task is a questionnaire for medical research to illustrate how SMS progresses over the years.
Fund raising to date has been aimed at generating sufficient revenue solely to maintain the group, although the longer term aim is raise sufficient money to re-start SMS-specific research (none is currently carried out in the UK and Ireland). To that end, the group is actively seeking a high-profile patron and sponsors.
Women appear most likely to fall victim to SMS. The age range is wide, with some victims presenting in their teens. However, the majority are aged 30 and over.
SMS has many variants. Sadly, there are no specific tests to determine which variant a sufferer has; it can only be determined in the way the condition presents and progresses. Classic SMS develops gradually over time and has no cure. Drug treatment, such as diazepam and baclofen are the first line treatments.
Background: In simple terms, everyone has an immune system that helps ward off infections. We also have an auto-immune system which, when compromised, in effect becomes our enemy. It sees a part of our own bodies as alien and begins to destroy it.
Most sufferers appear to have at least one other auto-immune condition. The most common (approximately 48%) is insulin dependent diabetes, (IDDM). This is due to an enzyme called glutamic acid decarboxylase (GAD). Everyone has GAD, but when it is compromised by anti-bodies (which are present in both conditions), it is destroyed. In IDDM the destruction of GAD affects the transmission of insulin between the pancreas and the liver. In SMS, the destruction of GAD affects the transmission of nerve impulses, causing rigidity and painful spasms.
The following are Liz’s observations of symptoms, obtained by talking to group members since 1998. There appear to be four main core symptoms:
• Rigidity
• Spasms
• Anxiety
• Startle Response
They present during everyday and routine activities, including:
Climbing Stairs: Walking upstairs (with a hand rail) may not pose much of a problem, but walking down — even with a hand rail — can at times be virtually impossible. The same problem is evident when walking down a slope. The reason for this is that even though the same muscles are in use, they work differently when used for different activities.
Crossing Roads: This is provoked by unexpected and inexplicable distress. For example, at a pedestrian crossing, when a car stops the sufferer seizes up, even though he/she knows it is safe. It causes rigidity and/or spasms, leaving the sufferer feeling unreasonably stupid and embarrassed. The cause of this bizarre reaction is probably twofold: Firstly, as strange as it may sound to non sufferers, the sufferer has a desperate need to be in control, but because the car has stopped, the driver has control. In effect, this tells the sufferer they must cross the road, self-control is lost and the symptoms kick in.
Falling: This is distressingly common among sufferers. Non sufferers use their muscles to compensate when they trip over a bump, however small. For SMS sufferers such apparently little things are a potential nightmare. Evidence shows it can be something as seemingly trivial as a piece of Lego left on the floor that can trigger a fall. When encountering the slightest of hazards, the body simply does not respond as it should. It invariably goes ridged and is followed by a fall. If help is needed to get up, the control element (see crossing roads) kicks in. Anyone helping can’t do the obvious — help the sufferer get up — as this exacerbates the problem. The helper must let the sufferer take the lead, ie the sufferer probably has to tell the helper when they are ready to be helped. In effect, most sufferers find it easier to hold on to the helper and pull themselves up rather than be helped up.
Weather: Wind, frost, snow and ice are major hazards for any sufferer. Wind can blow them over; frost, snow or ice are impossible to walk on because of the fear of falling. In fact, any shiny surface causes anxiety. Even if it is not actually slippery, the brain perceives it to be a sheet of ice and therefore it cannot be traversed.
Anxiety: Sufferers normally cope in much the same way as anyone else in genuinely anxious situations. However, trivial events that non-sufferers take in their stride generate serious anxiety in sufferers. For example, an activity one undertakes time after time can suddenly, and for no apparent reason, cause extreme anxiety that inevitably will be followed by rigidity and or spasms. Because of this, many sufferers find themselves housebound because of the embarrassment and/or fear of an anxiety attack happening where others can see them. It’s worth noting here that the function of GAD is to convert glutamate to gamma-aminobutyric acid (GABA). GABA serves as a natural anti-anxiety compound. As a significant number of SMS sufferers have antibodies to GAD, not surprisingly they also have anxiety. Tragically, anxiety exacerbates both rigidity and spasms.
Startle Response: Sights, sounds and touch — any or all, no matter how seemingly insignificant, can provoke one or all of the symptoms of rigidity, spasms or anxiety.
Sight: Even something as ‘normal’ as having one’s photograph taken is only one of many instances where the sufferer, even when they know what is about to happen, can still generate an adverse reaction. Anything in a sufferer's peripheral vision can cause problems. For example, walking into a room where balloons are on the floor. This can suddenly become a fear totally disproportionate to the reality. Balloons move as one walks past them, causing anxiety and of course the fear of one popping.
Sounds: A knock at the door, the toaster popping up, any unexpected sound — loud or quiet — can and does trigger a reaction.
Touch: Most people ‘jump’ if they are tapped unexpectedly on the shoulder, but that would be the full extent of the reaction. For SMS sufferers the slightest ‘touch’ can trigger a spasm. For example, accidentally brushing a hand against something, knocking over an object — the list of examples of the startle response is endless. Not all sufferers experience the same degree of anxiety, spasms or rigidity; some are affected to a much higher degree and completely disproportionate to the trigger.
Mobility among sufferers is extremely variable. Bathing can be an arduous task, as the rigidity often prevents the sufferer getting in and out of the bath without help – if indeed they can even get a bath. A walk-in shower, with a seat and grab rails is often an easier solution. In the home, many ambulant sufferers can get around reasonably well because they are in familiar surroundings; it’s their comfort zone with familiar things to hold on to, whether furniture, door handles, grab rails, etc. In the garden, more help may be needed, perhaps a three-wheeled walker or someone’s supporting arm for both physical and emotional support. Beyond the home, it is a completely different scenario — the great outdoors is an area as far out of the comfort zone as one can get and the world is a very threatening place.
Agoraphobia (or at least somewhere under the same umbrella) appears to affect many sufferers. There seems to be some respite for sufferers who are not in wheelchairs but who use a walking aid to walk close to a wall or hedge. Anxiety is evident when there is a gap to cross. For example, if you were to take a sufferer who is able to walk with a stick, crutches or a walker and ask them to walk down a narrow corridor, they could possibly do it unaided because of the ‘safety’ of the surrounding walls. Ask that same person to take one step, or in some cases just stand, in the open unaided, and they would — if they could — sit down slowly, or they would simply fall over. The floor, it seems, is safe, because there is nowhere else to fall
There are a number of sufferers — mainly women — who have problems with bladder control. Some require catheterisation. Although this appears to commonly affect women more than men, perhaps men are a little shy of revealing such a problem? Some also find bowel movements bring on spasms. In these cases, enemas are administered on a regular basis to alleviate the problem.
Stress, as with most illnesses, makes all aspects of SMS considerably worse.
The observations listed above do not cover every fear or phobia noted over the years. There are many more, and as they become apparent, this report will be updated.
Dr Peter Brown MD FRCP
Consultant Neurologist
The Stiff Man syndrome is a rare disorder first identified in the 1950s. In its most typical form, the classical Stiff Man Syndrome, it gradually develops and slowly progresses over several years, thereafter only fluctuating by modest amounts. Patients complain of painful spasms around the back, stomach and sometimes thighs and neck These spasms may be precipitated by unexpected events, such as a door slamming, a car backfiring or being tapped. Spasms may be also precipitated by attempts to move. As the disease progresses, there is often some degree of fixed postural abnormality, usually an arching of the low back.
The classical Stiff Man Syndrome is associated with a number of other diseases. The most common of these is insulin-dependent diabetes mellitus. Also reasonably common are the co-existence of thyroid disease, vitiligo and pernicious anaemia. All these diseases have in common an autoimmune (self-allergic) nature and it is likely that the Stiff Man Syndrome has a similar basis. There are some variants of the Stiff Man Syndrome, which have been more recently recognised. The first of these, sometimes called the Stiff Limb Syndrome, is similar but painful spasms and occasionally fixed deformities, affect the legs including the feet rather than the back or the stomach more rarely the hand can be affected. Patients with this variant of Stiff Man Syndrome are far less likely to have diabetes mellitus or other autoimmune conditions, and tend not to have anti-GAD antibodies (see later). Rarely there are more aggressive forms of the Stiff Man Syndrome, which lead to progressive disability over a number of years. This variant is sometimes called the Jerking Stiff Person Syndrome or Progressive Encephalomyelitis with rigidity.
INVESTIGATIONS
The most important investigation is antibody testing. The classical Stiff Man Syndrome carries an antibody marker, which is an antibody to an enzyme found both in the pancreas and in nerve tissue. This antibody is called anti-GAD and it occurs in high concentrations in the Stiff Man Syndrome. Much lower concentrations are sometimes found in diabetes without the Stiff Man syndrome. More rarely some other antibodies may be associated with the Stiff Man conditions. One of these is called antiamphiphysin. Where this is found there is often also a co-existing tumor. However, this combination is very rare. Electrical recordings from the affected muscles (termed EMG) can be useful in making the diagnosis. Here the characteristic finding is an inability of the affected muscles to relax. Scans of the spinal cord can be useful in excluding a structural cause such as a disc or cyst in the spinal cord. The latter may rarely masquerade as the Stiff Man Syndrome. Finally, it is sometimes necessary to examine the fluid from around the spine (CSF) by lumbar puncture. This is to look for signs of active inflammation.
TREATMENT
Patients usually respond to combinations of Diazepam and Baclofen, often in reasonably high dosage. These medications can be sedating. Unusually, Baclofen can cause a slight inflammation of the liver. Dependence does not seem to be a problem with Diazepam usage in the Stiff Man Syndrome. These drugs are given orally, usually three times a day. Other oral treatments may occasionally be helpful, such as Vigabatrin, Sodium Valproate, Tizanidine and Gabapentin. These too may be sedating in high dosages. Where all drug treatments fail to give sufficient relief from spasms and pain, treatments directed against the underlying allergic condition may be useful. The choices here consist of steroids (either intravenous or orally), plasma exchange (a technique in which your blood is washed of antibodies) or intravenous pooled immunoglobulins. The latter is probably the preferred treatment of this kind. It usually requires a few days in hospital and the treatment has to be repeated every few months. The infusion of immunoglobulins can be associated with headache. As immunoglobulins are a blood product there is a theoretical and remote risk of catching a viral illness. Precautions are taken to keep this risk to an absolute minimum.
OUTLOOK
None of these treatments leads to a cure. However, they are able to control symptoms in the majority of patients. This is particularly true in the classical Stiff Man Syndrome, which has areasonably good outlook. It tends to be a little bit more difficult to control symptoms in the Stiff Limb Syndrome, and some of these patients will require help with mobility. Progressive encephalomyelitis with rigidity is a difficult condition to treat and has a poor prognosis.
Information from other sources
Stiff Man Syndrome is a rare condition affecting one in a million or one in two million people. The condition is oharacterised by stiffness of muscles with painful spasms. It is associated in about 30-40% of patients with diabetes, usually insulin dependent diabetes. Both insulin dependent diabetes and Stiff Man Syndrome feature immune responses to an Enzyme Glutamic acid decarboxylase (GAD). -
Results to date suggest that in both diseases antibodies can be detected to GAD, though in some patients with Stiff Man Syndrome the antibody titres are high. In addition, in both diseases there is a T-cell response to GAD, but the part of GAD, which is the target for this response, seems to differ between diabetic patients and those with Stiff Man Syndrome.
other names
Stiff Person Syndrome
Moersch Woltman Syndrome