What is Renal Acidosis?

Renal acidosis, also known as renal tubule acidosis, is a condition characterized by improper filtration of acids from the body which results in a rising acid level in the blood. People with renal acidosis have blood with an unusually low pH balance and they can develop complications as a result. This condition is sometimes the result of a genetic condition, and may also be caused by damage to the kidneys incurred as a result of disease. There are treatments available for renal acidosis which can be discussed with a doctor.

Normally, the kidneys filter out acids and express them in the urine while retaining bicarbonate which acts as a buffer for acids in the body to keep the blood from becoming too acidic. In someone with renal acidosis type I, filtration of acids is not adequate. In type II, also known as proximal renal acidosis, the patient does not retain bicarbonate. Type III is rare, and a blend of both these types, while type IV involves hyperkalemia, in which the blood level of potassium is high.

In the early stages of renal acidosis, a patient may not have any symptoms. As the condition progresses, the patient can experience bone disease such as rickets, in which the bones soften and bend. Patients may also develop kidney stones which can be seen on x-ray and which cause symptoms such as urinary obstruction and pain. As kidney function becomes increasingly impaired, the patient can develop more serious symptoms.

Diagnosis of renal acidosis is done by testing the patient's urine and blood. The urine will be relatively alkaline in composition, while the blood will be acidic, reflecting the fact that acids are not being expelled in the urine as they should be. Treatment can include supplementation with bicarbonate to neutralize the acids, and control of the patient's diet. In type IV renal acidosis the patient must avoid potassium and stay properly hydrated to avoid developing complications associated with hyperkalemia.

This condition was first described in the 1930s. If a patient is believed to be at risk of renal acidosis a doctor may recommend periodic evaluations to check the pH of the blood so that early signs of rising acid levels can be identified and addressed. It is important to receive treatment for this condition because it can lead to severe complications including complete kidney failure if it is neglected and the treatment is relatively easy.