Kidney diseases: why they’re so common

Posted on 18 December 2017

Kidney disease is a common cause of hospitalisation. We look at the different types of kidney disease – such as chronic kidney disease – and what the risk factors and treatment options are.

Like the heart, liver and lungs, your kidneys are vitally important. Situated just behind your abdominal cavity and underneath the ribs, their primary function is to purify your blood and produce hormones. Any interference with kidney (renal) function should therefore be taken very seriously. Testing for kidney disease in high risk patients is an absolute must.

‘Renal disease is a worldwide public health problem, something which is on the increase,’ says Dr Riaan Flooks, a Bloemfontein-based nephrologist. ‘And this applies to both acute and chronic forms of the disease. While the exact causes of this increase are unknown, possible underlying factors include increasing life expectancy, presence of additional diseases like obesity or hypertension, and social deprivation.’

Renal disease can be divided into two categories, Acute Kidney Injury (AKI) and Chronic Kidney Disease (CKD). And as Dr Flooks explains, it is important to differentiate between the two types.

‘Acute Kidney Injury is characterised by an abrupt decrease in renal function,’ says Dr Flooks. ‘While this disease is present in approximately 2% of hospital in-patients, it is more common in those who are critically ill. Potential causes of AKI include reduced renal blood supply (prerenal), infections and compromised immunity (intrinsic), as well as post-renal obstructions like tumours or kidney stones.

‘Chronic Kidney Disease, on the other hand, sees a patient suffering from structural or functional kidney damage for a period of at least three months. This would be also be associated with a reduced Glomerular Filtration Rate (GFR) – the function of your kidneys tested by looking at your age, general health status and creatinine levels in your blood (a chemical waste molecule that is generated from muscle metabolism). Diabetes and associated hypertension are the most common potential causes of CKD, as are Glomerulonephritis, congenital diseases and HIV/Aids.

In South Africa, HIV-associated renal disease is most probably the second most common cause of CKD.

Comprehensive treatment options are available for most types of kidney diseases, and survival rates are good. And while hemodialysis and peritoneal dialysis apply to both forms of kidney disease, there is a third option available only to those falling into the chronic disease category.

‘Renal transplantation is the extra dimension reserved for patients diagnosed with CKD,’ says Dr Flooks. ‘But a transplant is only required at the end stage of renal disease, freeing a patient from the constraints of constant dialysis.’