The particles of heavy elements, isotopes or the invasive radioactive nucleons, and, in addition, the abuse of substance, leading to a total that exceeds the limits of the concentration in the haematic circulation lose their solubility and form precipitates and conglomerates which adhere to the capillaries, in the tissues and in various organs.
They are the toxic factors for macromolecular degradation at cell structure level, which initiate the start to form uric acid, viewing in excessive growing percentage in hemoleucograms and simultaneously in the urine concentrations.
The increasing of the ion concentration in urine induces to decrease the pH and the urine volume and implicit to reduce the substances level that naturaly inhibits the forming of the renal calculi (citrate, magnesium, Tamm-Horsfall mucoprotein) are the main favoring factors for the debut and the development of the urolithiasis [Pietrowice PK, 2006].
The renal lithiasis, the renal calculi or the kidney stones are crystalline mineral deposits that form at the kidney level, where the concentration of some minerals filtered from blood in urine increases accumulating more phosphorus, calcium, magnesium, uric acid, calcium oxalate, calcium phosphate and urate and develops crystals which are normally excreted in urine.
The renal calculi determine urinary tracks obstruction, causing acute back pain which may radiate bilateral lumbar on lower limbs, leading to the difficulties of movement. From the statistical data of reference it results that the annual incidence of the renal calculi is of about 1% at the general level of population. The forming of microcalculi, develops from microscopic crystals, firstly on the haematic flux, afterwards through conglomeration in renal filters, respectively in the Henle’s loop and distal tubules or collectors where they attract one another electrochemically and in time develop as kidney stones, from a few microns to 1-2 centimeters size, visible on echograph, with sferical solid structures, layered or not, sharp, composite or irregular as coraliform type, depending on the weight of the biochemical degradation compounds as calcium oxalate type or urates [Wolf JS, 2012].
The renal calculus composition varies according to the type of the substances in excess, from a single chemical substance, to various chemicals disposed in several layers, having sometimes a center composition completely different from that of the external layers. From 95-97% of cases on renal calculi composition were determined the following chemical compounds: uric acid, calcium oxalate, calcium phosphate, struvite (magnesium ammonium phosphate) and associated calculi with a bacterial infection.
The renal calculi contain about 75% calcium. In rare cases the renal calculi are composed from cystine (determined as hereditary disorder on cystine excretion) and from abuse of substance in drugs such as sulfamide category [Paterson R., 2010].



Aggravating factor in renal lithiasis is provoked by the proliferation of chronic urogenital infections of different origins, accompanying and continuously maintain the growth of renal stones. In cases of kidney failure come in addition the cases extremely complicated by the toxic presence, in blood and urine, of the heavy metals and/or the radioactive isotopes concentration, whose sum exceeds the conventional admitted limits and which have a latent cumulative effect on the affected body.
Aggravating factors occur most frequently among people from the population accidentally exposed in risk areas, as a result of some emissions from chemical or nuclear accidents, or professionally exposed to different types of substances and compounds with heavy metals, including medical staff using Laboratory long time for dental amalgam compounds and / or systematically administered radiopharmaceutical products in clinical investigations.
Exponentially aggravating factors are increasing in the case of the urinary tract infections of young children, who receive, by error, or accidentally, contrast agents with barium, iodine, strontium, colloidal gold, gadolinium, technetium, etc. for radiographic or scintigraphy diagnostic outside of the pharmacovigilance rules contained in the Nuclear Medicine Treaties.
Radiopharmaceutical contrast substances being initially activated by thermal neutrons, afterwards highlighted by radiological repeated X or gamma radiation fluxes, have latent invasive effects and residual cumulative effects with unpredictable and/or somber repercussions.
Being vehiculated by the circulatory systems, the contrast substance is immediately dispersed in the entire body, but is retained in excessive concentrations, with cumulative effects in thymus gland, thyroid, suprarenals, kidneys, liver, spleen and in the bone marrow.
Nuclear Medicine Treaties warn on the fact that after any scintigram, over 85% from the administered dose is not eliminated immediately, and the remaining contrast agent in vital organs was determined statistically in blood and urine concentrations of extreme risk after a measurable time in years without any safe prognosis.