The Role of the Clinical Laboratory in Nutritional Assessment
Aruna Bakhru in Nutrition and Integrative Medicine, 2018
Calcium oxalate kidney stones are the leading type of kidney stones. Oxalate is naturally found in many foods, including fruits and vegetables, nuts and seeds, grains, legumes, and even chocolate and tea. Some examples of foods that contain high levels of oxalate include peanuts, rhubarb, spinach, beets, chocolate, and sweet potatoes. Another common type of kidney stone is a uric acid stone. Red meat and shellfish have high concentrations of a natural chemical compound known as a purine. High purine intake leads to a higher production of uric acid, which then accumulates as crystals in the joints or as stones in the kidneys. Again, based on the type of kidney stone, different diets and medication are prescribed. Monitoring 24-hour urine is often used in patient management to reduce reoccurrence.52
Envisioning Utilization of Super Grains for Healthcare
Megh R. Goyal, Preeti Birwal, Santosh K. Mishra in Phytochemicals and Medicinal Plants in Food Design, 2022
Oxalates are harmful substances and potential risk for the human body. It is not metabolized in human body and excrete through urine. The higher consumption of the oxalates results in the reduced availability of the certain elements, which can lead to hyperoxaluria. This can cause a risk of calcium oxalate stone formation in the kidneys since oxalate and divalent ions are capable of forming insoluble complex in the gut [87, 107, 159]. Moreover, the presence of the oxalic acid in the human diet leads to various harmful effects such as gastrointestinal irritation, reduced minerals availability, impaired blood clotting, and contraction of muscles mainly attributed to the higher amounts of crystalline calcium contents deposits in the cells (Table 10.6). The recommended levels of oxalates in the human diet are estimated to be 50–200 mg per day [107].
Multiple choice questions (MCQs)
Tristan Barrett, Nadeem Shaida, Ashley Shaw, Adrian K. Dixon in Radiology for Undergraduate Finals and Foundation Years, 2018
A 50-year-old man is diagnosed with ureteric colic on CT. However, on follow up KUB the calculus is found to be radiolucent. Which of the following could the calculus be composed of? Calcium oxalate.Calcium phosphate.Uric acid.Xanthine.Magnesium ammonium phosphate.
Oral administration of oxalate-enriched spinach extract as an improved methodology for the induction of dietary hyperoxaluric nephrocalcinosis in experimental rats
Published in Toxicology Mechanisms and Methods, 2018
Abhishek Albert, Vidhi Tiwari, Eldho Paul, Sasikumar Ponnusamy, Divya Ganesan, Rajkumar Prabhakaran, Selvi Mariaraj Sivakumar, Selvam Govindan Sadasivam
Increased urinary excretion of oxalate is derived from dietary and endogenous sources. Common dietary sources with high oxalate content include green leafy vegetables, beets, strawberries, nuts, cocoa, dark chocolates and tea infusions (Ritter and Savage 2007; Schroder et al. 2011; Mahdavi et al. 2013). Oxalic acid is a non-essential dietary component available at varying concentrations in all plant species. Reports from previous studies demonstrate that oxalate rich leafy vegetables such as spinach can accumulate oxalate between 800 and 12 576 mg/100 g dry matter (Siener et al. 2006; Savage and Martensson 2010). Spinach extract used in this study showed maximum oxalate content among various dietary sources. Minor variations in oxalate content observed among spinach extracts harvested from different regions can be attributed to the subtle environmental and growth conditions.
Could the region you live in prevent or precipitate kidney stone formation due to mineral intake through tap water? An analysis of nine distribution regions in Flanders
Published in Acta Chirurgica Belgica, 2023
Michaël M. E. L. Henderickx, Simone J. M. Stoots, Joyce Baard, Guido M. Kamphuis
Calcium, magnesium, potassium, sodium and sulphate all influence the risk of kidney stone formation. Calcium can lower the risk of kidney stone formation by binding with oxalate in the intestine. However, without calcium, oxalate is reabsorbed in the bloodstream and released in the urine, increasing the risk of kidney stone formation [12]. Therefore, patients with calcium oxalate stones, the most common type of kidney stones, are advised to consume two to three products rich in calcium. Magnesium, then again, keeps calcium dissolved in the bloodstream, thus preventing calcium to be released in the urine and subsequently lowering the risk of kidney stone formation due to an excess of calcium in the urine (hypercalciuria). Additionally, magnesium may also diminish urinary oxalate excretion by reducing the intestinal reabsorption [12–15]. Similarly, potassium intake has been associated with a lower risk of kidney stone formation. A low potassium intake can impair the reabsorption of calcium, leading to hypercalciuria and thus a higher risk of kidney stone formation [13,16].
Calcium-sensing receptor promotes calcium oxalate crystal adhesion and renal injury in Wistar rats by promoting ROS production and subsequent regulation of PS ectropion, OPN, KIM-1, and ERK expression
Published in Renal Failure, 2021
Xiaoran Li, Siyu Chen, Demei Feng, Yuqiang Fu, Huang Wu, Jianzhong Lu, Junsheng Bao
In addition, we found that rats with nephrolithiasis showed low urinary calcium and citrate and high urinary oxalate compared to control animals. Oxalate is a more important promoter of kidney stones and exhibits 15-fold greater efficacy on urinary calcium oxalate saturation than calcium [43]. Notably, we observed low urinary oxalate in our rat nephrolithiasis model treated with GdCl3 compared with group B; one possible explanation for this finding is that CaSR increased free calcium, which binds to oxalate and thus reduces urinary oxalate. In addition, the main risk factor for recurrence of calcium oxalate stones is thought to be urinary citrate deficiency. Urinary citrate inhibits the formation of stones by inhibiting nucleation and growth [44]. Our results showed that urinary citrate levels decreased in the rat nephrolithiasis model. The CaSR inhibitor NPS-2390 increased the urinary citrate concentration and reduced crystal deposition in the rat nephrolithiasis model compared with group B. Therefore, we speculated that NPS-2390 might be a potential drug for the treatment of nephrolithiasis, especially when exposed to ethylene glycol, but the effect must be further verified by animal experiments and clinical trials before introducing it in clinical practice.
Related Knowledge Centers
- Acid Dissociation Constant
- Equilibrium Constant
- Oxalic Acid
- Ion
- Dianion
- Salt
- Sodium Oxalate
- Dimethyl Oxalate
- Conjugate
- Hydrogenoxalate