Urolithiasis and its Physiology

Image

Journal of Kidney Treatment and Diagnosis is a peer-reviewed, Open Access journal focused on Clinical Nephrology practice and related diseases. The journal publishes reviews and papers of international interest describing original research concerned with clinical and experimental aspects of nephrology.

Kidney stone disease, also known as urolithiasis, is when a solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the body in the urine stream. If a stone grows to more than 5 millimeters (0.2 in), it can cause blockage of the ureter, resulting in severe pain in the lower back or abdomen. A stone may also result in blood in the urine, vomiting, or painful urination.

 In those who have had stones, prevention is by drinking fluids such that more than two liters of urine are produced per day. If this is not effective enough, thiazide diuretic, citrate, or allopurinol may be taken .Otherwise pain control is usually the first measure, using medications such as nonsteroidal anti-inflammatory drugs or opioids

PHYSIOLOGY

Hypocitraturia

Hypocitraturia or low urinary-citrate excretion (defined as less than 320 mg/day) can cause kidney stones in up to 2/3 of cases. The protective role of citrate is linked to several mechanisms; in fact, citrate reduces urinary supersaturation of calcium salts by forming soluble complexes with calcium ions and by inhibiting crystal growth and aggregation.

Super saturation of urine

When the urine becomes supersaturation with one or more calculogenic (crystal-forming) substances, a seed crystal may form through the process of nucleation. Heterogeneous nucleation (where there is a solid surface present on which a crystal can grow) proceeds more rapidly than homogeneous nucleation (where a crystal must grow in a liquid medium with no such surface), because it requires less energy. Supersaturation of the urine is a necessary, but not a sufficient, condition for the development of any urinary calculus. Supersaturation is likely the underlying cause of uric acid and cystine stones, but calcium-based stones (especially calcium oxalate stones) may have a more complex cause.

Inhibitors of stone formation

Normal urine contains chelating agents, such as citrate, that inhibit the nucleation, growth, and aggregation of calcium-containing crystals. Other endogenous inhibitors include, nephrocalcin prothrombin F1 peptide, and bikunin (uronic acid-rich protein). The biochemical mechanisms of action of these substances have not yet been thoroughly elucidated. However, when these substances fall below their normal proportions, stones can form from an aggregation of crystals.

Sufficient dietary intake of magnesium and citrate inhibits the formation of calcium oxalate and calcium phosphate stones; in addition, magnesium and citrate operate synergistically to inhibit kidney stones. Magnesium's efficacy in subduing stone formation and growth is dose-dependent.

Journal of Kidney Treatment and Diagnosis publishes the manuscripts that are directly or indirectly based on variegated aspects of Articles that are submitted to our journal will undergo a double-blind peer-review process to maintain quality and the standards set for academic journals.  The review process will do by our external reviewers which are double-blind. The comments will upload directly to the editorial tracking system. Later the editor will check the comments whether it is acceptable or not.   The overall process will take around 21 days under with the editor. After acceptance by the editor, it will be published on the Press page.  Authors can submit their manuscripts to online submission portal.

With Regards,
John Robrert                            
Managing Editor
Journal of Kidney Treatment and Diagnosis

Email:  kidney@emedsci.com