The kidneys remove waste products from the bloodstream. They also secrete hormones, help control the blood pressure, and keep the proper amount of salt, electrolytes and water in the body. In acute renal failure, the kidneys are suddenly losing their ability to function. It can happen in just a matter of days or weeks. Five percent of all hospital admissions are due to acute renal failure, Suzanne Watnick, M.D., Director of the Dialysis Unit at the Portland V.A. Medical Center reports in "Current Medical Diagnosis and Treatment."
Uremia
The liver stores protein and breaks it down into amino acids whenever they are needed by the body. It also converts amino acids into urea and sends urea to the kidneys. In acute renal failure, the kidneys cannot excrete urea efficiently. This leads to uremia, or too much urea in the bloodstream. This is toxic, since urea has nitrogen. The symptoms include weakness, nausea and vomiting, confusion, seizures, jerky hand movements and even coma, states James McMillan, M.D., Chief of Nephrology at the V.A. Loma Linda Healthcare System in "The Merck Manual for Healthcare Professionals."
Uremic Pericarditis
Pericarditis is the inflammation of the pericardium, or the membrane that surrounds the heart. In uremic pericarditis, uremia causes this inflammation. The symptoms may include chest pain, fever and cough. The chest pain usually becomes worse when people lie down and eases when they sit up and lean forward. The pain also lessens when they do not breathe deeply. The pericardium has two layers. The inflammation can cause fluid to build up between those two layers. This can lead to too much fluid surrounding and pressing on the heart, as explained by Elizabeth Corwin, Ph.D., in "Handbook of Pathophysiology."
Lab Indications
A lab test determines the level of BUN and creatinine. BUN is the medical abbreviation for blood urea nitrogen. In acute renal failure, there are high levels of urea and nitrogen in the bloodstream, which causes uremia. The skeletal muscle breaks down creatine phosphate for its energy needs. This results in a substance called creatinine. If the kidneys are functioning, they will excrete creatinine. But in acute renal failure, there are high levels of creatinine in the bloodstream. There will also be high levels of phosphorus in the blood. Dr. Watnick explains in "Current Medical Diagnosis and Treatment," that the damaged kidneys cannot excrete phosphorus. If the acute renal failure has taken several weeks, a blood test may show that the person is anemic. The kidneys normally secrete a hormone called erythropoietin, or EPO. This hormone stimulates the production of red blood cells. As the kidneys fail, they are secreting less EPO.
References
- "Current Medical Diagnosis and Treatment 2010"; Stephen McPhee, M.D., Maxine Papadakis, M.D.; 2010
- "Handbook of Pathophysiology"; Elizabeth Corwin, M.S.N., Ph.D., F.N.P.; 2000
- "The Merck Manual for Healthcare Professionals": Acute Renal Failure (ARF)
