The kidneys are vital organs. They remove waste material, determine body fluid level, influence electrolyte concentrations, and even help regulate blood pressure. We are lucky that we have two, for kidney failure (also called renal failure) is a very serious condition.
Kidney failure comes in multiple forms, from reduced function (called renal insufficiency) to complete collapse (known as acute or chronic renal failure). Reduced function may occur, for example, when the top lobe of one of the kidneys flattens, reducing the number and surface area of nephrons, the small units that filter the blood. Or, a kidney may stop working altogether.
The causes are as varied as the types of renal failure. Decreased blood flow from constricted blood vessels is one. Hypertension is another. Necrosis, the actual death of kidney cells, is yet one more. Some autoimmune diseases result in kidney malfunction.
Symptoms also cover a wide range. In 70% of cases oliguria (decrease in urine output) is present, or it may stop altogether (anuria). The feet or legs may swell from excess fluid retention. Lethargy and decreased appetite are possible. We may bruise more easily or experience prolonged bleeding from a cut. Even seizures or coma are possible.
But since any of these symptoms may result from many other diseases as well, the only way to know is to get a proper diagnosis.
The exam starts with a check for physical signs. Using a stethoscope, the doctor will listen for heart murmur or crackling in the lungs, a sign of excess fluid. That is followed up with a urinalysis and blood tests. The lab will look for blood in the urine, excess creatinine levels, and check serum potassium levels. A BUN (blood urea nitrogen) test is performed. Ultrasound may be used, and sometimes an MRI (Magnetic Resonance Imaging) is performed.
Kidney malfunction is a serious condition, but it can be treated.
Dietary changes are the minimum one can expect. It will become important to control fluids, both the amount and type. Diuretics may be used to help the kidneys lose fluid. It will also be important to control electrolytes such as sodium and potassium. It will be essential to monitor and regulate blood pressure.
In more severe cases, blood potassium levels may be controlled by IV calcium treatments. Diabetes is often either a cause or a consequence of kidney disease and that entails regulating glucose and insulin levels. In extreme cases, dialysis is necessary.
The most serious stage is known as chronic renal failure or end-stage renal disease. This can be fatal, but need not be. It is more common when a kidney malfunction results from physical injury or surgery, or a severe infection. Treatments range from intermittent to continuous dialysis to kidney transplants to artificial kidneys worn on the outside of the body.
When properly treated, kidney disease can be kept under control and sometimes cured entirely. Naturally, the prognosis will depend on the underlying causes, but it is not uncommon for the most severe symptoms to be sharply curtailed within a few weeks. In many cases, full or near-full function is restored within months.