Causes Of Metabolic Acidosis

The acidity of the blood is tightly controlled by the kidneys, respiratory system and chemical buffers in the blood. Normal blood pH levels are 7.4. If blood pH drops below 7.35, symptoms of acidosis may occur. A study in the May 2010 issue of the journal Nature Reviews Nephrology reports that metabolic acidosis is characterized by decreases in plasma bicarbonate levels, carbon dioxide levels, and pH. The symptoms of this condition are deep breathing, chest pain, palpitations, anxiety, nausea, abdominal pain and possibly coma and death. Chronic metabolic acidosis may cause weight loss, muscle weakness and osteoporosis. The presence of metabolic acidosis is indicative of an underlying disease. It is detected and classified by arterial blood gas sampling and measurement of plasma bicarbonate levels and electrolyte concentration.

Ketoacidosis

In the condition of ketoacidosis, fatty acid metabolism is stimulated. Fatty acids are broken down in the liver to ketoacids, which are released into the blood and transported to cells to use as an energy source. A build-up of ketoacids in the blood can cause metabolic acidosis. Ketoacidosis is prevalent in type 1 diabetics, and it is also caused by chronic alcohol consumption, starvation and rare congenital diseases.

Kidney Failure

The kidney regulates plasma bicarbonate levels and hydrogen ion concentration. A fluctuation in either of these molecules alters acid-base balance in the body. A common complication of kidney failure and chronic kidney disease is metabolic acidosis.

Gastrointestinal Disorder

Severe diarrhea and vomiting can result in excessive loss of bicarbonate from the body. When bicarbonate levels drop, the buffering capacity of the blood is lessened, and its acidity increases. A study published in the Kathmandu University Medical Journal reported that metabolic acidosis and accompanying electrolyte balances are often responsible for mortality in children with diarrhea and dehydration.

Lactic Acidosis

When oxygen levels are low, cells will still metabolize glucose for energy. This causes the build-up of lactic acid in the blood and consequently a decrease in blood pH. Amino acid catabolism also produces lactic acid. Shock, diabetes, liver and kidney disease, ethanol toxicity, exercise, rare congenital disorders and drugs can cause lactic acidosis.

Drugs

A review article published in the journal Clinics in Endocrinology and Metabolism reported that the most common chemicals and drugs that cause metabolic acidosis are alcohol, sugar alcohols, cyanide, carbon monoxide, toluene, hydrochloride salts of amino acids, carbonic anhydrase inhibitors, biguanides, salicylates, amphotericin, spironolactone and non-steroidal anti-inflammatory drugs. Additionally, a study in the journal Nature Reviews Nephrology reported that trimethoprim, amphotericin B, penicillins, ciprofloxacin, demeclocycline and various antitubercular agents can cause kidney dysfunction, leading to metabolic acidosis.