Nephrolithiasis: Formation of stones in the KIDNEY.Kidney Calculi: Stones in the KIDNEY, usually formed in the urine-collecting area of the kidney (KIDNEY PELVIS). Their sizes vary and most contains CALCIUM OXALATE.Calcium Oxalate: The calcium salt of oxalic acid, occurring in the urine as crystals and in certain calculi.Hypercalciuria: Excretion of abnormally high level of CALCIUM in the URINE, greater than 4 mg/kg/day.Hyperoxaluria: Excretion of an excessive amount of OXALATES in the urine.Nephrocalcinosis: A condition characterized by calcification of the renal tissue itself. It is usually seen in distal RENAL TUBULAR ACIDOSIS with calcium deposition in the DISTAL KIDNEY TUBULES and the surrounding interstitium. Nephrocalcinosis causes RENAL INSUFFICIENCY.Oxalates: Derivatives of OXALIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that are derived from the ethanedioic acid structure.Urolithiasis: Formation of stones in any part of the URINARY TRACT, usually in the KIDNEY; URINARY BLADDER; or the URETER.Uric Acid: An oxidation product, via XANTHINE OXIDASE, of oxypurines such as XANTHINE and HYPOXANTHINE. It is the final oxidation product of purine catabolism in humans and primates, whereas in most other mammals URATE OXIDASE further oxidizes it to ALLANTOIN.Calcium Metabolism Disorders: Disorders in the processing of calcium in the body: its absorption, transport, storage, and utilization.Urinary Calculi: Low-density crystals or stones in any part of the URINARY TRACT. Their chemical compositions often include CALCIUM OXALATE, magnesium ammonium phosphate (struvite), CYSTINE, or URIC ACID.Ethylene Glycol: A colorless, odorless, viscous dihydroxy alcohol. It has a sweet taste, but is poisonous if ingested. Ethylene glycol is the most important glycol commercially available and is manufactured on a large scale in the United States. It is used as an antifreeze and coolant, in hydraulic fluids, and in the manufacture of low-freezing dynamites and resins.Orthosiphon: A plant genus of the family LAMIACEAE that contains pimarane-type diterpenes. Several species of Orthosiphon are also called Java tea.Cystinuria: An inherited disorder due to defective reabsorption of CYSTINE and other BASIC AMINO ACIDS by the PROXIMAL RENAL TUBULES. This form of aminoaciduria is characterized by the abnormally high urinary levels of cystine; LYSINE; ARGININE; and ORNITHINE. Mutations involve the amino acid transport protein gene SLC3A1.Oxalobacter formigenes: The sole species of the genus Oxalobacter consisting of straight or curved gram-negative rods with rounded ends. Cells are nonmotile, nonsporing, and use oxylates as the only source of CARBON and energy, with formate and CARBON DIOXIDE as end products. They are isolated from lake sediments and from the rumen or large bowel of humans and animals. (From Bergey's Manual of Determinative Bacteriology, 9th ed)Ureteroscopy: Endoscopic examination, therapy or surgery of the ureter.Hyperoxaluria, Primary: A genetic disorder characterized by excretion of large amounts of OXALATES in urine; NEPHROLITHIASIS; NEPHROCALCINOSIS; early onset of RENAL FAILURE; and often a generalized deposit of CALCIUM OXALATE. There are subtypes classified by the enzyme defects in glyoxylate metabolism.CitratesRenal Tubular Transport, Inborn Errors: Genetic defects in the selective or non-selective transport functions of the KIDNEY TUBULES.Citric Acid: A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability.Uromodulin: A glycosyl-phosphatidyl-inositol (GPI) - anchored membrane protein found on the thick ascending limb of the LOOP OF HENLE. The cleaved form of the protein is found abundantly in URINE.Potassium Citrate: A powder that dissolves in water, which is administered orally, and is used as a diuretic, expectorant, systemic alkalizer, and electrolyte replenisher.Receptors, Calcium-Sensing: A class of G-protein-coupled receptors that react to varying extracellular CALCIUM levels. Calcium-sensing receptors in the PARATHYROID GLANDS play an important role in the maintenance of calcium HOMEOSTASIS by regulating the release of PARATHYROID HORMONE. They differ from INTRACELLULAR CALCIUM-SENSING PROTEINS which sense intracellular calcium levels.Oxalic Acid: A strong dicarboxylic acid occurring in many plants and vegetables. It is produced in the body by metabolism of glyoxylic acid or ascorbic acid. It is not metabolized but excreted in the urine. It is used as an analytical reagent and general reducing agent.Glucose Transport Proteins, Facilitative: A family of monosaccharide transport proteins characterized by 12 membrane spanning helices. They facilitate passive diffusion of GLUCOSE across the CELL MEMBRANE.Pyelonephritis, Xanthogranulomatous: A chronic inflammatory condition of the KIDNEY resulting in diffuse renal destruction, a grossly enlarged and nonfunctioning kidney associated with NEPHROLITHIASIS and KIDNEY STONES.Sodium-Phosphate Cotransporter Proteins, Type IIc: A non-electrogenic sodium-dependent phosphate transporter. It is found primarily in apical membranes of PROXIMAL RENAL TUBULES.Hyperparathyroidism, Primary: A condition of abnormally elevated output of PARATHYROID HORMONE due to parathyroid HYPERPLASIA or PARATHYROID NEOPLASMS. It is characterized by the combination of HYPERCALCEMIA, phosphaturia, elevated renal 1,25-DIHYDROXYVITAMIN D3 synthesis, and increased BONE RESORPTION.Acidosis, Renal Tubular: A group of genetic disorders of the KIDNEY TUBULES characterized by the accumulation of metabolically produced acids with elevated plasma chloride, hyperchloremic metabolic ACIDOSIS. Defective renal acidification of URINE (proximal tubules) or low renal acid excretion (distal tubules) can lead to complications such as HYPOKALEMIA, hypercalcinuria with NEPHROLITHIASIS and NEPHROCALCINOSIS, and RICKETS.Gout: Hereditary metabolic disorder characterized by recurrent acute arthritis, hyperuricemia and deposition of sodium urate in and around the joints, sometimes with formation of uric acid calculi.Hypophosphatemia: A condition of an abnormally low level of PHOSPHATES in the blood.Crystallization: The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Ureteral Calculi: Stones in the URETER that are formed in the KIDNEY. They are rarely more than 5 mm in diameter for larger renal stones cannot enter ureters. They are often lodged at the ureteral narrowing and can cause excruciating renal colic.Lithotripsy: The destruction of a calculus of the kidney, ureter, bladder, or gallbladder by physical forces, including crushing with a lithotriptor through a catheter. Focused percutaneous ultrasound and focused hydraulic shock waves may be used without surgery. Lithotripsy does not include the dissolving of stones by acids or litholysis. Lithotripsy by laser is LITHOTRIPSY, LASER.Calcium Phosphates: Calcium salts of phosphoric acid. These compounds are frequently used as calcium supplements.Sodium Chloride Symporter Inhibitors: Agents that inhibit SODIUM CHLORIDE SYMPORTERS. They act as DIURETICS. Excess use is associated with HYPOKALEMIA.Urine: Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Uricosuric Agents: Gout suppressants that act directly on the renal tubule to increase the excretion of uric acid, thus reducing its concentrations in plasma.Sodium Bicarbonate: A white, crystalline powder that is commonly used as a pH buffering agent, an electrolyte replenisher, systemic alkalizer and in topical cleansing solutions.Allopurinol: A XANTHINE OXIDASE inhibitor that decreases URIC ACID production. It also acts as an antimetabolite on some simpler organisms.Practice Guidelines as Topic: Directions or principles presenting current or future rules of policy for assisting health care practitioners in patient care decisions regarding diagnosis, therapy, or related clinical circumstances. The guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by the convening of expert panels. The guidelines form a basis for the evaluation of all aspects of health care and delivery.Societies, Medical: Societies whose membership is limited to physicians.Guideline Adherence: Conformity in fulfilling or following official, recognized, or institutional requirements, guidelines, recommendations, protocols, pathways, or other standards.American Cancer Society: A voluntary organization concerned with the prevention and treatment of cancer through education and research.Guidelines as Topic: A systematic statement of policy rules or principles. Guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by convening expert panels. The text may be cursive or in outline form but is generally a comprehensive guide to problems and approaches in any field of activity. For guidelines in the field of health care and clinical medicine, PRACTICE GUIDELINES AS TOPIC is available.Citrus: A plant genus of the family RUTACEAE. They bear the familiar citrus fruits including oranges, grapefruit, lemons, and limes. There are many hybrids which makes the nomenclature confusing.Fatty Acids: Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Kidney Tubules, Proximal: The renal tubule portion that extends from the BOWMAN CAPSULE in the KIDNEY CORTEX into the KIDNEY MEDULLA. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the U-shaped LOOP OF HENLE.Ammonia: A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.