Dopa responsive dystonia
BMJ 2010; 340 doi: https://doi.org/10.1136/bmj.c668 (Published 04 March 2010) Cite this as: BMJ 2010;340:c668
- Karen Low, ST1 paediatric doctor1,
- Teresa Harding, patient2,
- Philip Jardine, consultant paediatric neurologist3
- 1c/o Bristol Royal Hospital for Children, Upper Maudlin Street, Bristol BS2 8BJ
- 242 Braikenridge Close, Clevedon
- 3Frenchay Hospital, Frenchay, Bristol BS16 1LE
- Correspondence to: T Harding harding{at}blueyonder.co.uk
- Accepted 13 May 2009
I walked perfectly normally until I was four. Then soon after contracting measles my headmistress noticed I was dragging one leg and not walking correctly.
I was six when they sent me to the children’s hospital. The doctor told my mother, “I don’t know why you’ve brought this child here—you’re doing it for attention and you’ve wasted my time.” My mother says that if they had watched me walk out to the car they would have seen the problem, but they just thought I was attention seeking. In my old notes it says that I had a psychological problem.
My legs continued to deteriorate. I struggled to walk and sometimes collapsed in the street. I would gradually become worse as the day went on and my father often had to carry me. This continued until I was nine when my parents arranged a private appointment with a neurologist. They felt this was the only way to make someone see what was happening.
The consultant admitted me to Frenchay Hospital, Bristol, for observation. The floors were very slippery so I found it very difficult to walk and my feet pulled inward. Initially, my parents were told I had muscular dystrophy; but then the doctors decided that this was the wrong diagnosis because my muscles were not wasting away. I remained under the care of the neurologist for the next nine years, during which time I had five years of physiotherapy that caused my legs to become weaker, rather than stronger. Various tests, including a brain scan, found nothing wrong. I had iron callipers on both legs, and then I progressed to plastic splints. My posture became very poor and I continued to struggle to walk. On every annual visit I was told I was “unique” and that they did not know what was wrong with me.
At 18 I had a kidney infection and could not stop vomiting, so my GP gave me antibiotics and an anti-sickness injection. Things immediately went from bad to worse. For several hours my ankles pulled inwards, my whole body went stiff, and I was unable to relax. My doctor did not understand what had happened. I had no strength in my legs at all, was reduced to crawling, and had lost my sense of balance. I was off sick from work as a telephonist for six months and went from 161 lbs to 108 lbs. When I saw the neurologist for my annual appointment he said, “Whatever happened to you?” I told him, but nobody could explain my illness and there was nothing more he could do for me. My condition still baffled medical staff and that year they wrote me off.
Living with my disability
I am quite an outgoing person and I had brilliant friends throughout school who really helped me. I have never let my illness get to me and nobody has been nasty about it, but I did suffer because I couldn’t do the same activities as everyone else. I could never go on school trips or to school camp, because in those days facilities to help disabled people did not exist.
So I lived with it—dragging my feet and not being able to walk without holding on to something or somebody for support. Most of the time I was forced to use a wheelchair.
In 1990 I moved to Clevedon with my future husband and had my first son. I had been told I would be unable to conceive, so it was a shock when I became pregnant. I love being a mum, but my disability made it difficult to begin with. Social services provided me with home help five days a week to assist me with the baby and housework.
My lowest point was after I had had my first son. I had gone over on my ankle many times. It was so painful and weak that I couldn’t look after my son properly, so I went to my GP.
I was sent back to Frenchay Hospital and saw a doctor who asked about my legs rather than my ankle injury, which was difficult to understand. He wanted to know how far I could walk and how things were during the day and the evening. When I asked him the reasons for these questions, he said “If we can get you on the right medication, it can change your life.”
The turning point
How right he was. I was told that I had a condition called dopa responsive dystonia. I was started on co-beneldopa 125 mg, one daily for the first week, increasing to six daily within six weeks. After taking the first tablet I noticed an instant effect. I felt as though I had strength in my legs for the first time in years. I then stabilised at two tablets daily and continued to improve slowly over the next months. Gradually my balance and posture improved and my body began to relax. In April 1992 I realised my dream of walking down the aisle, with my splints still in place under my wedding dress. On our honeymoon I discarded my splints and started the difficult process of teaching myself to walk again.
My second son was born in April 1994. During my pregnancy my consultant advised that I reduce my medication, which I did without complications. I increased the dose again after the birth.
I am now 45 years old—I walk normally and have a very active family life. My great love is line dancing. I was always afraid of the illness returning and I’ve had a few blips that really worried me. I asked the consultant if I would get used to the tablets and whether the condition would come back. He reassured me that should that ever happen; I can just have my medication increased.
I still class myself as disabled—I still have the condition and if I don’t take the medication I can’t walk. On some occasions when dancing I have suddenly thought I had better sit down or I would fall over.
Since my diagnosis other family members have been tested. Now we know that my mother, my eldest son, both my aunts, and some of their children have the condition. They are all being treated for it. If Dr Jardine hadn’t put in the effort to investigate my family they would never have known that they have dopa responsive dystonia as well.
I continue to take co-beneldopa and will for the rest of my life. It is a small price to pay for the life I thought I would never have.
A doctor’s perspective
The form of dopa responsive dystonia described here is inherited as an autosomal dominant trait and is caused by mutations in a gene for guanosine-5-triphosphate (GTP) cyclohydrolase (GCH1). This enzyme is essential for normal dopamine synthesis. The symptoms and signs of dopa responsive dystonia are varied, but onset of dystonia in early childhood with marked variation in symptoms throughout the day is typical. For this reason, there might be a mismatch between the child’s symptoms and the signs that are evident to a doctor at a particular time. A range of other neurological symptoms and signs have been described in this condition including tremor, spasticity, and ataxia. Many people with dopa responsive dystonia are misdiagnosed with other neurological conditions, but the diagnosis can be confirmed in several ways, including DNA analysis. Dopa responsive dystonia is often completely curable with levodopa (L-dopa) replacement. Some patients respond quickly to a low dose of L-dopa, whereas others need a larger dose and respond more slowly.
Cerebral palsy describes a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non progressive disturbances that occurred in the developing fetal or infant brain. Not all conditions that affect posture and movement and start in early childhood are a type of cerebral palsy. The prevalence of cerebral palsy varies throughout the world but is about 2 in 1000 live births in developed countries. The prevalence of DRD is unknown, but is a much rarer condition. In 14 years as a consultant paediatric neurologist I have diagnosed five new cases. There are likely to be many undiagnosed patients in the UK.
Magnetic resonance brain imaging is crucial in evaluating the cause of a patient’s cerebral palsy. Although normal brain imaging does occur in some people with cerebral palsy, this raises the possibility of an alternative diagnosis. The condition starts in early childhood and does not fluctuate markedly as the day goes by. Although the functional abilities of a child with CP might change over the years—for instance losing the ability to walk independently in adult life—a marked progression in symptoms should raise the possibility of an alternative diagnosis. Cerebral palsy does not usually recur within families. A first degree relative with cerebral palsy should certainly lead to the diagnosis being questioned. A growing list of rare genetic and metabolic disorders, can masquerade as cerebral palsy. Accurate diagnosis is important because some of these conditions are treatable—or even curable—and some might recur in families.
No doctor can be omniscient. There will always be patients with rare conditions that the doctor is not familiar with. Keeping an open mind about potential diagnoses and listening carefully to the patient’s story is important.
Lessons to be learnt
The bad
I felt quite let down by the medical profession in my younger years. It felt like no one listened to my parents, really looked at me, or understood the gravity of the situation.
Having my symptoms labelled as “psychological” is still particularly upsetting.
In my younger years I was unable to participate in many activities that other people my age could do and sometimes felt excluded. Nowadays disabled facilities are so much better and allow for people with disabilities to be much more included.
The good
I have now met doctors who believe in listening to mothers’ instincts and paying attention to what the patient is telling them. This would be my advice for doctors reading this—always listen to what the patient is telling you.
One of the most important things was that someone could give my problem a name and could then do something to treat it.
I have now met doctors who believe in excellent communication. My current specialist is so accessible, he listens to all my concerns and doesn’t even mind if I contact him occasionally with email queries, and he always gets back to me very quickly.
I hope that I can help other people who have this condition. I have become actively involved with the Dystonia Society and speaking to families who are newly diagnosed.
Additional Resources
The Dystonia Society (www.dystonia.org.uk)—A UK wide charity providing support, advice, and information for anyone affected by dystonia
Action for Dystonia, Diagnosis, Education & Research (ADDER) (www.actionfordystonis.co.uk)—UK based group aiming to advance education, promote treatment, and offer support for patients
Contact a Family (www.cafamily.org.uk/Direct/d51.html)—Dystonia page of Contact a Family, the UK site that allows users to contact other families in similar positions. Specifically aimed at families with disabled children
Dystonia Support 4 U (www.dystonia-support4u.com/about.php)—UK based support group
The European Dystonia Federation (www.dystonia-europe.org)—This portal includes links to websites about dystonia in different European countries
Dystonia Bulletin Board (www.dystonia-bb.org/forums/asd/)—Sponsored by the Dystonia Medical Research Foundation, provides support and discussion for patients, family members, and caregivers with all forms of dystonia
Notes
Cite this as: BMJ 2010;340:c668
Footnotes
This is one of a series of occasional articles by patients about their experiences that offer lessons to doctors. The BMJ welcomes contributions to the series. Please contact Peter Lapsley (plapsley{at}bmj.com) for guidance.
Competing interests: None declared.
Patient consent: The patient is one of the authors.
Provenance and peer review: Not commissioned; externally peer reviewed.