Stage 3 kidney disease results in a glomerular filtration rate (GFR) of 30 to 59, which the National Kidney Foundation defines as a moderate decrease in kidney function. Learn more about the diagnosis and management of this condition to better understand its effects.
Causes of chronic kidney disease include diabetes, high blood pressure, chronic illnesses, autoimmune disorders, damage to the structures of the kidneys, polycystic kidney disease, severe kidney infection, drugs, industrial toxins and congenital defects. Acute renal failure is classified as prerenal, renal and postrenal. Prerenal causes of kidney failure include severe dehydration, heart attack, pulmonary embolism, liver failure, septic shock and renal artery obstruction. Renal causes of acute kidney failure include injury to the kidney tubules, hemorrhage, surgery, toxins and immune disorders. Postrenal causes of kidney failure include bladder obstruction, ureter obstruction and congenital defects. Acute renal failure can lead to chronic kidney disease if it is not treated quickly.
As kidney function declines, the kidneys lose their ability to filter wastes and maintain normal fluid and electrolyte levels. This causes abnormal potassium, sodium, phosphorus, creatinine and blood urea nitrogen (BUN) levels. Patients with hyponatremia (low sodium levels) must restrict their fluid intake to avoid dangerous complications. Kidney disease contributes to the development of diabetes and hypertension, making early detection and proper treatment essential for preserving kidney function and reducing the risk of complications.
The diagnosis of stage 3 kidney disease involves laboratory tests and imaging studies. The basic metabolic panel identifies abnormal levels of waste products and electrolytes in the blood, which indicates the presence of kidney disease. Using the patient’s blood creatinine level, age, race and gender, the laboratory technicians calculate her estimated glomerular filtration rate. This provides a measurement of how well the kidneys are functioning. Urine tests identify abnormal levels of protein and microalbumin in the urine, another indicator of chronic kidney disease. Imaging studies identify urinary obstructions, kidney masses and other conditions that can contribute to kidney disease.
Treatment for this kidney disease stage is designed to prevent complications and preserve existing kidney function. You doctor may recommend a special diet that restricts the intake of phosphorus and potassium. This diet is necessary because people with kidney disease cannot maintain normal levels of these substances in the blood. Restricting your sodium intake prevents fluid retention, swelling and high blood pressure (hypertension). If you have developed high blood pressure as a result of your condition, your doctor will prescribe medications to control your blood pressure and reduce the risk of serious complications.
While many kidney disease patients do not have symptoms during stages 1 and 2 of the disease, stage 3 kidney disease is when many symptoms appear. Complications of this stage of kidney disease include kidney pain, fatigue, swelling of the lower legs, foamy urine, blood in the urine and difficulty sleeping. As waste products accumulate in the blood, you may experience nausea, vomiting and itching, as well as feelings of malaise and illness. Treatment reduces the amount of wastes in the blood and eliminates some of these complications.
Davita: Stage 3 of Chronic Kidney Disease. Accessed January 25, 2010.
National Kidney and Urologic Diseases Information Clearinghouse: The Kidneys and How They Work. Accessed January 25, 2010.