5.7 million French people have chronic kidney disease or chronic renal failure, making it a more common disease than diabetes or cancer. Chronic kidney failure (CKD) refers to a more or less significant reduction in kidney function. The kidneys permanently and irreversibly lose their ability to properly filter the blood. Waste and fluids then accumulate in the body. Due to lack of screening, it is estimated that a large proportion of people with kidney failure are unaware of their kidney failure. However, when it is detected too late, we lose the opportunity to slow its progression and its complications, particularly cardiovascular.
Chronic kidney failure: long time without symptoms!
This chronic kidney failure is asymptomatic (without symptoms) until a very advanced stage in the vast majority of cases. Renal failure is therefore not diagnosed in a symptomatic patient. “It is most often during a systematic assessment that kidney failure is diagnosed, by a biological examination”, explains Dr Benjamin Pradère, urological surgeon and also Member of the Cancerology Committee of the French Urology Association. It can also be revealed during examinations carried out before carrying out a CT scan with injection of contrast products (certain products cannot be administered in cases of renal insufficiency or before the administration of nephrotoxic drugs (which can alter the functioning of the kidneys).
Sometimes, pathologies associated with kidney failure such as heart failure can cause symptoms (edema of the lower limbs, shortness of breath) leading to the prescription of biological tests allowing the early diagnosis of kidney disease.
Chronic kidney failure: what screening?
Screening for chronic kidney failure is done with very simple dosages. “A blood test is taken to measure the creatinine and estimate the GFR (DFG). A urine sample analysis is done to measure the ratio albumin/creatinine which makes it possible to detect abnormal albuminuria”informs Professor Patrick Rossignol, nephrologist, head of the Medical Specialties – Nephrology-hemodialysis department at the Princess Grace Hospital Center (CHPG) in Monaco, and coordinator of the FCRIN INI-CRCT network.
He explains that the challenge is not only to diagnose this renal failure but to treat and prevent decline in kidney function with hygienic-dietary measures and taking medications. Hygiene-dietary and pharmacological interventions make it possible to slow down the progression towards end-stage renal failure, dialysis and the need for transplantation, and to prevent the appearance of cardiovascular complications. “A new class of drugs has been added to the class of antihypertensive drugs (blockers of the renin angiotensin aldosterone system) used for around thirty years: SGLT-2 inhibitorsnow usable in France in this indication, and which offer additional protection at the renal and cardiovascular level”, informs the nephrologist.
This alerts to the fact that failure to diagnose kidney failure early is a loss of opportunity for patients who cannot benefit from early dietary and drug interventions.
Biological signs of chronic renal failure
Blood and urine tests make it possible to diagnose chronic kidney failure and the stage of the disease. The classification takes into account stages 1 to 5 of kidney failure chronic: from kidney damage without kidney failure, to chronic kidney disease with slightly reduced GFR, moderate chronic kidney failure (CKD), severe chronic kidney disease (CKD), end-stage chronic kidney disease (CKD).
Who should benefit from kidney failure detection?
“As chronic kidney failure is asymptomatic for a long time, it is recommended to carry out screening in people most at risk of kidney failure,” informs Professor Rossignol who details: “all the hypertensive and all diabetics should benefit from this screening once a year.” This annual screening for chronic kidney disease is also recommended for people over 65, people with cardiovascular disease and people with obesity. “Kidney function is also monitored in people with only one kidney, whether they were born with only one kidney or have undergone a nephrectomy) or in contexts of genetic diseases such as polycystic kidney disease which can lead to renal failure”, informs Dr. Pradère.