Definition
Lactic acidosis causes an increased concentration of lactic acid in the blood, which causes the pH value to fall below the physiological range and consequently shifts towards acidic values. A change in the pH value due to acidosis can have serious effects. Normally, human blood is slightly alkaline or alkaline due to the dissolved salt. With acidosis, the blood becomes slightly acidic.
Causes of latatacidosis
Lactate acidosis is usually caused by a disturbed cell metabolism, in which the oxygen-consuming (aerobic) glucose utilization cannot functionally take place. As an intermediate product of the incomplete glucose metabolism, lactate often accumulates as a result, since the energy production from glucose to lactate is also possible without oxygen. This leads to an increased exhaustion of the anaerobic-lactacid energy supply (anaerobic = without oxygen).
During lactate acidosis, pyruvate is formed from glycolysis under oxygen deficiency and is converted to lactic acid. Glycolysis is the process in the body in which carbohydrates are broken down into monosaccharides and fed into the bloodstream. The liver is able to break down lactate to a certain extent and compensate the lactate acidosis to a certain extent.
However, when liver function drops, the accumulation of lactate can no longer be stopped and the body overacidifies. Lactic acidosis often occurs in diabetics in the context of diabetic ketoacidosis. Liver and kidney diseases as well as blood poisoning (sepsis) can also be the cause.
Normally, excess lactate in the liver is used in the process of glucose production (gluconeogenesis) and is thus broken down. However, if liver disease is present, this process may be restricted and lactate accumulates. Especially in the case of massive lactate accumulation, the damaged liver is no longer able to compensate for the condition.
Another cause is life-threatening conditions such as shock, pulmonary embolism and major operations, in which tissue is sometimes insufficiently supplied with blood and consequently no longer receives sufficient oxygen, which is why the body has to resort to energy production through the formation of lactate. In the context of high blood sugar levels in diabetics, for example, the body is severely dehydrated so that too little blood remains in the vascular system. This leads to a so-called hypovolemic shock.
As a result of this shock, organs are insufficiently supplied with blood and therefore too little oxygen and a lactic acidosis develops. Various drugs, such as the anti-diabetic drug metformin in particular, can also lead to lactic acidosis. Drugs that lead to lactic acidosis usually inhibit the respiratory chain, which means that less oxygen is produced and available for energy production, which is why it is necessary to switch to the lactic acid metabolism.
A lack of thiamine (vitamin B1), in the context of the Beriberi syndrome, which is often provoked by malnutrition and alcoholism, can also lead to lactic acidosis. Thiamine deficiency throttles the citrate cycle, causing the intermediate product pyruvate to accumulate, which can be converted into lactate. Lactic acidosis can also occur in the context of tumor diseases, since some tumors produce lactate.
All articles in this series:
