A group of disorders in which the excretion of hydrogen ions and/or the reabsorption of bicarbonate in the kidneys is impaired, are identified as renal-tubular acidoses.

The mentioned disease i-dRTA can be inherited or later on in the life be acquired. The urine shows an abnormal acidic value, do to a underexcretion of hydrogen ions (pH > 5.5). To compensate for this negative effect, the organism uses the blood buffer system, i.e. by shifting electrolytes between blood and urine. The chronic process is associated frequently with complications of kidney calcification or a formation of kidney stones. Furthermore, the bone microarchitecture is deteriorated in the long term due to the net loss of calcium. It is known from the literature that a reasonable proportion of patients with kidney stones or osteoporosis have this underlying disease.