Symptoms of kidney failure include shortness of breath, lethargy and confusion. MedicineNet states that kidney failure can be sudden with no advance symptoms.
The kidneys help the body remove any waste from the blood. Kidney function naturally decreases as people age. The patient may present potassium build up during a blood test. Kidneys also help control blood pressure, so high blood pressure may be a sign that the kidneys are not functioning correctly. If the patient has diabetes, controlling diet and insulin levels can help restore kidney function. A transplant or dialysis may be the only cure if the kidneys have begun completely shutting down according to MedicineNet.