Patients with kidney problems are twice as likely to die from coronavirus, doctors have found.

About 48 per cent of Covid-19 patients admitted to ICUs in London and Birmingham with new acute kidney injury – likely triggered by the virus – succumbed to the disease. And 50 per cent of those with pre-existing kidney problems, such as chronic kidney disease, died.

But for patients whose kidneys functioned normally 21 per cent died from the virus.

The researchers, led by Imperial College London, warned this meant medics should be on ‘high alert’ for kidney problems, and said this meant anyone suffering this should be admitted to intensive care earlier.

As many as three million people suffer from kidney problems in the UK, while in the US there are 37million sufferers. The condition is often undiagnosed because it has very few symptoms.

Dr Sanooj Soni, an organ damage expert and intensive care consultant at Imperial College London and who led the study, warned many patients with kidney problems do not know their organs are damaged.

‘If you end up getting kidney problems on top of severe Covid-19 symptoms your mortality rate doubles right away – that’s a very big deal,’ he told The Telegraph.

‘Attention needs to be paid to Covid-19 patients with any form of kidney disease or injury, and every effort made to prevent progression of this disease or injury to reduce mortality in this cohort of patients.’

He fears many patients with severe renal problems were turned away from ICU in the first wave of the pandemic because they were considered unlikely to survive.

In the study, they also found that one-fifth of patients who had survived Covid-19 still required treatment for their kidneys after they were discharged from intensive care.

Doctors monitored 372 patients admitted to intensive care between March 10 and July 23, during the first wave of the coronavirus pandemic.

Of these as many as 216 also had kidney problems. As many as 139 participants included in the study died in hospital.

They had an average age of 60 years, were mostly men, and the majority – 76 per cent – were from BAME backgrounds. Each of these factors is known to increase the risk of death from Covid-19.

It is unclear how having kidney problems while suffering from the virus can increase a patients risk of death.

But the doctors suggested in their study – published by the journal of Anaesthesia – that it may be due to the impact of the infection on the body overall rather than a direct attack on the vital organs by the virus.

Previous studies have suggested Covid-19 may directly infect the kidneys and cause damage in a similar way to in the lungs – but it is unclear how it would reach them. Experts have previously said that coronaviruses do not generally travel in the bloodstream, which they would need to do to reach the kidneys.

Instead, the study authors suggested the increased death rate for those with the virus and kidney problems may be due to ‘lung-to-kidney cross talk’.

According to previous studies, this is when an initial injury to the lungs is followed by kidney failure several days later due to a cytokine storm – when the immune system creates such a severe reaction to an infection that it damages the body’s cells.

They also pointed to drug toxicity from medicines playing a role in kidney problems and an increased death rate, alongside other contributory factors including heart problems and high blood pressure.

What is chronic kidney disease and how do I diagnose it?

Chronic kidney disease is when the organs gradually decline and use their function, meaning the body struggles to filter enough waste products from its bloodstream.

It has been divided into five stages with the first two having few symptoms.

The NHS says that the condition is often diagnosed with blood and urine tests, and in many cases is found by accident when people are being checked for a different problem.

They recommend visiting your GP if you are suffering from the following problems:

  • Weight loss or poor appetite
  • Swollen ankles, feet or hands
  • Shortness of breath
  • Tiredness
  • Blood in your pee
  • Peeing more than usual, particularly at night

Tests can diagnose the issue by checking the level of proteins in your bloodstream.