Kidney failure

Food poisoning is usually a short term infection without any long term consequences but, experts suspect that the bacteria (or viruses/parasites) which cause food poisoning may also be linked to certain diseases such as kidney failure.

What appears to be the case is that a bout of food poisoning triggers an abnormal response in the immune system which causes it to attack its own cells. This autoimmune reaction leads to a range of diseases which include Guillain-Barre syndrome, reactive arthritis and kidney failure.

However, further research is needed to confirm this link and an explanation as to why this happens.

What is kidney failure?

Kidney failure (also known as renal insufficiency) is used to describe a state in which the kidneys are unable to filter out waste products from the blood as per normal.

There are two types of kidney failure: acute and chronic kidney failure although there are cases where people have developed both acute and chronic kidney disease.

This is known as acute on chronic renal failure.

The kidneys are responsible for filtering out toxins and waste products from the blood: the waste products (urine) being diverted to the bladder for excretion from the body.

The kidneys also regulate electrolyte levels and blood pressure and produce hormones such as calcitriol and erythropoietin.

Causes of kidney failure

These vary according to whether someone has acute or chronic kidney failure. Acute kidney failure occurs as a result of accident, injury, excess amount of toxins or a drug overdose.

Chronic kidney failure develops over a long period of time and is caused by a range of diseases which include diabetes and high blood pressure. It is also caused by drug overdose, e.g. aspirin.

Kidney failure can also occur as a complication of food poisoning caused by the e coli or shigella bacteria, or from eating toxic mushrooms.

Symptoms of kidney failure

These include the following (for both acute and chronic kidney failure):

• Blood or protein in the urine
• Frequent/less frequent urination
• Difficulty in urinating
• ‘Foamy’ urine
• Vomiting
• Diarrhoea
• Weight loss
• Itchy skin
• Impotence
• Fluid retention in the ankles, hands or feet
• Tiredness
• Muscle cramps
• Lack of appetite
• Dizziness
• Nausea

However, many of these symptoms can be avoided if the condition is treated at an early stage.

Diagnosing kidney failure

A problem with this and especially with chronic kidney disease is that the symptoms develop over a long period of time. This means that the symptoms don’t often appear until the disease has reached am advanced stage.

By that stage the kidneys have lost most if not all of their ability to function which means that dialysis or a kidney transplant is required.

What is recommend is that anyone who is considered a ‘high risk’for kidney failure (which also includes people who have suffered from bacterial food poisoning) is screened for this disease on a regular basis.

Your GP will advise you further about screening.

You will be asked about your symptoms and your medical history. If you have experienced food poisoning especially e coli or shigella poisoning then mention it to your GP.

If you have suffered food poisoning as a result of eating poisonous mushrooms then tell your GP about that.

It is important to do so as complications can occur after a bout of food poisoning, one of them being kidney failure. This is particularly the case for people who are considered to be vulnerable in regards to food poisoning, for example, the elderly.

Glomerular filtration rate test

Your GP will examine you and will refer you for tests which include blood, urine and a ‘glomerular filtration rate’ (GFR) test. A GFR test measures the amount of waste products filtered out by your kidneys per minute.

A healthy pair of kidneys can filter at least 90ml of waste products but if this figure is lower then it may be an indicator of kidney disease.

But several GFR tests will be needed to confirm this diagnosis.

Additional tests include a kidney biopsy and a kidney scan. A kidney scan is usually an MRI or CT scan which aims to detect any abnormalities in the kidneys or a blockage in the urine flow.

Treatment for kidney failure

This depends upon the extent of your illness. Chronic kidney disease is measured in stages so the more advanced the stage of your disease the more complex the treatment.

Treatment will also depend upon the cause of your kidney failure. If, for example, it has been caused by high blood pressure then you can be given medication to lower this.

Dietary changes may be necessary. Severe cases will require dialysis or even a kidney transplant.