Renal function impairment

A patient with a long history of depression, which had been treated over the years with various medications including anti-depressants, was referred to an NHS psychiatrist because he was experiencing severe mood fluctuations. He had also recently shown violent tendencies towards other people.

The psychiatrist considered treatment with lithium at a dose of 100mg. At the time of the test, the patient's urea and creatinine levels were marginally high at 8.1 mmol/L and 104 umol/L. Repeat tests were ordered and the psychiatrist advised the addition of lithium to the claimant's current anti-depressant regime if the second readings were normal.

Two weeks later, the patient saw his GP, a member of the MDU. The GP had previous training in psychiatry and was responsible within the practice for the management of patients requiring psychiatric medication.

Before starting the patient on lithium, the GP rechecked the patient's urea level and noted that it had improved since a reading taken six months earlier - it was now 9.4 mmol/L compared to 11.1 mmol/L. The GP felt it would be in the patient's best interests to commence lithium medication despite being aware of the pre-existing mild renal impairment.

The patient was prescribed lithium on four occasions over a four-month period, and during that time his urea and creatinine levels increased but remained within the range for mild renal impairment. The GP carried out several renal function tests over the period to monitor any effect of the lithium treatment, as well as seeing the patient in his clinic.

Shortly afterwards, the patient was diagnosed with chronic kidney disease stage 3 and over the next two years continued to suffer a decline in renal function. He was assessed for renal transplant.

The patient brought a claim against both the Trust and the GP member in which it was alleged that he was an unsuitable candidate for lithium and the GP member was negligent in starting lithium treatment due to pre-existing concerns over renal function. It was also alleged that the GP breached his duty of care by continuing with lithium despite increasing urea and creatinine levels.

Further, it was alleged that the lithium caused the patient to suffer acute kidney failure, and permanent kidney damage with progressive deterioration in renal function over a number of years so that he required haemodialysis and his life expectancy was reduced.

The MDU obtained evidence from independent GP and psychiatric experts that was supportive of the GP's management. The psychiatric expert noted that the doctor was well qualified to assess the patient's psychiatric condition and treatment thanks to his experience and pre-existing training. In the event, the monitoring took place more frequently than was recommended at the time, and it was therefore perfectly reasonable for the doctor to start lithium and to monitor the patient in the way he did.

Expert evidence was also obtained on causation from a consultant nephrologist who opined that significant renal damage would only be caused by decades of lithium use and even in the early years of taking the drug, the expert would have expected any renal damage due to lithium toxicity to have been entirely reversible. There were other significant co-morbitities that contributed to a gradual decline in the patient's renal function, which had improved on cessation of the lithium, and it was noted that the patient did not start the haemodialysis it had been alleged he now required.

In response to the MDU expert evidence, the claimant made a small offer of settlement based on their own expert's revised view that the lithium caused additional tiredness and fatigue only. The MDU rejected this and the claim was subsequently dropped.

Andrew Norman
Claims handler

This page was correct at publication on 17/02/2016. Any guidance is intended as general guidance for members only. If you are a member and need specific advice relating to your own circumstances, please contact one of our advisers.