Dr Samia Bushra's article was judged 'highly commended' in our clinical writing competition.
Pain is a very subjective symptom. So when my patient first presented with a request for more painkillers, I complied.
He was around 50 years old, Caucasian, six-feet tall and a bit overweight. It was a Friday evening and he had been given a prescription of gabapentin for ‘facial pain' by his neurologist, but had failed to pick it up at the hospital. In addition, he wanted his usual painkiller – codeine plus paracetamol. He was almost in tears. I issued a script and asked that he book an appointment for follow-up.
Over the next few months I got to know him better as a patient. He had had this pain for the past two years and it was gradually increasing, causing him to finally seek medical help a year before. His previous GP had referred him to hospital when nothing worked. Other causes of facial pain, including dental and maxillary surgical causes, had been investigated and ruled out. I decided to review and repeat his blood tests.
They were all reported as ‘normal', but I noted that his TFT was somewhat borderline. I did not have previous bloods to compare, but his TSH was at the upper limit of normal.
At the time, I also tried to address lifestyle changes. One problem was an ongoing knee pain that he claimed stopped him from losing weight. His knee examination was normal.
After excluding other causes for ongoing pain – and checking on time off work, home stresses and psychiatric illness – I repeated his TFTs and requested a thyroid antibody test. Repeated TSH was always above 5.6 and his thyroid antibodies were high. This was a man who still worked regularly and was only attending the surgery for his pain relief.
Wide-ranging effects
The thyroid gland affects the metabolism of muscles and nerves. It is widely known for ‘weight gain' and ‘feeling tired', but is also a cause of both polyneuropathy and mononeuropathy, and in long-standing hypothyroidism has been shown to cause patchy demyelination of nerves. It also causes myopathy, which in long-standing hypothyroidism manifests as weakness, decreased muscle reflexes and pain.
The advantage of being a GP is that one is able to see the patient as a whole, and so determine whether only reassurance is needed or the patient should have further investigation and treatment.
I decided he needed further assessment. I discussed the blood results with him and the fact that so far nothing had been found to explain his symptoms of pain. The blood results were within the normal range, but ‘normal' differs for each individual. So theoretically if his ‘normal' TSH used to be 1 or 2, he could have been gradually becoming hypothyroid and exhibiting symptoms.
He agreed to start on a low dose of thyroxine. I explained the symptoms of over-treatment and in the following few months monitored his response and blood levels of TSH and T4. It took up to a dose of 100µg of levothyroxine for his TSH to come down to around or below 2. He himself said he was ‘feeling so much better'.
His knee pain, although still an occasional problem, had not stopped him from being active and taking up a sport. His ‘thick ankles' were actually partly a result of hypothyroid swelling of the lower limbs.
My focus on getting his levels of TSH adequate and his enthusiasm for lifestyle change meant we forgot about his original complaint – facial pain. He had gradually stopped all his painkillers and gabapentin and was actually pain free.
Dr Samia Bushra is a GP in Dagenham, east London
