The death of a HIV sufferer who was mistakenly given an overdose in hospital has left a top expert "baffled".

Security officer Cadwell Mashininga, 44, from Redhill, died at St Helier Hospital after staff accidently gave him an overdose of the pneumonia treating drug Septrin, Croydon Coroner’s Court heard yesterday.

But the UK’s top HIV expert Professor Sebastian Lucas told the court that despite the mistake Mr Mashininga’s death was unrelated to the overdose.

Mr Mashininga, who was born in Zimbabwe, was suffering from pneumonia and a chesty cough.  He was transferred from Epsom Hospital to St Helier’s intensive care unit on April 26 because he needed the kidney support based at the hospital.

The court heard just after midnight Mr Mashininga was given an intravenous dose of Septrin however he was accidently given 24 hours worth in one dose - when it should have been divided by four and administered over a period of time.

The senior staff nurse on duty at the time described being "shocked" when he saw Mr Mashininga’s prescription chart -  he appeared normal and staff found the mistake was unlikely to cause him any harm.

At just before 2am Mr Mashininga sufferred a cardiac arrest, staff were unable to save him and he was declared dead soon afterwards.

Pathologist Professor Sebastian Lucas made his name in the early 90s with his pioneering work on AIDS and told the court: "He was diagnosed in his last illness but in fact informants in Kingston told me he had been diagnosed a decade ago in 2003.

"He was treated then but defaulted the next year and he was not treated again for the next nine years.

"He died of an acute lung process. The cause undetermined. I found this very disconcerting - I have seen thousands of HIV positive people."

He asked Mr Mashininga’s wife, a nurse, if he had inhaled anything in the week before he was admitted to hospital or whether he took any non-medical drugs. But his wife said he had only taken over-the-counter supplements.

The professor discounted the Septrin as being relevent to his death and said: "I’m presuming this was a nasty infection. Whether a virus or infection - that’s the nearest I got.

"We don’t know the state of his HIV at his death or just before. I think we are baffled."

Dr Palmer said the overdose of Septrin, although "unfortunate", did not in any way contribute to his death.

He said: "The best answer we can give you is we think it is a natural cause of death and not drug related.

"He shouldn’t have had the dose he had and that was troubling but Professor Lucas doesn’t think that is causative of his death.

"My sympathies to you and I’m sorry we can’t give you better answers. If professor Lucas can’t give you answers I don’t know anyone better in the country who could."

Dr Palmer recorded a natural cause of death due to an acute lung injury caused by HIV disease.

Sutton Guardian:

Dr James Marsh

Following the inquest joint medical director for the Epsom and St Helier Trust, Dr James Marsh, said: “On behalf of the trust, I would like to offer our sincere condolences to Mr Mashininga’s family and loved ones for their loss.

“We understand the coroner has confirmed Mr Mashininga’s cause of death was natural causes.

“However, we accept that at one point, Mr Mashininga was given a larger dose of his prescribed antibiotics than he should have been. 

"Although this did not contribute to the death of Mr Mashininga, we fully recognise that it should not have happened and are working to make sure a similar mistake will not happen again.

“That includes further training for all of our medical staff to ensure they always question prescriptions and the dosage.”