ascorbic-acid and Nephrocalcinosis

In developed countries, colonoscopy volume has increased dramatically over the past 15 years and is the principle method used to screen for colon cancer. Preparations used for colon cleaning have evolved over the past 30 years. Some preparations have been shown to be unsafe and are now used on a limited basis. There has been progress on limiting the volume required and on taste improvement.. This review provides an account of preparations used from 1980 when PEG-based preparations became widely available, until the present day. The review highlights their mechanism of action and principle toxicities. The handling of solutes and solute-free fluid by the colon is also reviewed.. The reader will gain a perspective on the factors considered in developing colonic purgatives and the rationale for choosing selected preparations based on patient factors such as age, co-morbidities and concomitant medications.. Although generally safe and effective, colonic purgatives have both acute and permanent toxicities. The safest preparations utilize PEG combined with a balanced electrolyte solution. Limitations of this preparation center on the volume required and poor taste. Alternative formulations are now available; however, those using sodium phosphate have fallen out of favor due to a risk of renal toxicity.

Topics: Ascorbic Acid; Calcium Phosphates; Cathartics; Citric Acid; Colonic Neoplasms; Colonoscopy; Humans; Hyperphosphatemia; Hypocalcemia; Nephrocalcinosis; Organometallic Compounds; Phosphates; Preoperative Care; Randomized Controlled Trials as Topic; Therapeutic Irrigation

Topics: Adolescent; Ascorbic Acid; Biochemical Phenomena; Biochemistry; Child; Classification; Diet; Genetics, Medical; Glycine; Glycolates; Humans; Hyperoxaluria, Primary; Infant; Kidney Calculi; Metabolic Diseases; Metabolism; Nephrocalcinosis; Oxalates; Pathology; Terminology as Topic; Uremia; Urine; Vitamin B 6 Deficiency

Nephrocalcinosis (NC) in preterm neonates has been described frequently, and small-scale studies suggest an unfavorable effect on renal function. The etiologic factors have not yet been fully clarified. We performed a prospective observational study to identify factors that influence the development of NC.. The study population consisted of 215 preterm neonates with a gestational age <32 weeks. Clinical characteristics and intake in the first four weeks of calcium, phosphorus, vitamin D, protein, and ascorbic acid were noted. Serum calcium, phosphate, vitamin D, magnesium, uric acid, creatinine, urea and urinary calcium, phosphate, oxalate, citrate, magnesium, uric acid, and creatinine were assessed at four weeks of age and at term. Renal ultrasonography (US) was performed at four weeks and at term. At term was defined as a postconceptional age of 38 to 42 weeks.. NC was diagnosed by means of US in 33% at four weeks and in 41% at term. Patients with NC at four weeks had a significantly higher mean intake of calcium (P < 0.05), phosphorus (P < 0.05), and ascorbic acid (P < 0.01) than patients without NC. They had a higher mean serum calcium (2.55 vs. 2.46 mmol/L, P < 0.01) and a higher mean urinary calcium/creatinine ratio (2.6 vs. 2.1 mmol/mmol, P < 0.05). Patients with NC at term had a lower birth weight (1142 vs. 1260 g, P < 0.05) and a lower gestational age (28.8 vs. 29.4 weeks, P < 0.05), were treated significantly longer with furosemide, dexamethasone, theophylline, and thiazides, developed chronic lung disease more frequently (40 vs. 16%, P < 0.001), and had a higher mean urinary calcium/creatinine ratio (2.7 vs. 2.3 mmol/mmol, P < 0.05) and a lower mean urinary citrate/calcium ratio (1.1 vs. 1.7 mmol/mmol, P = 0.005).. NC develops as a result of an imbalance between stone-inhibiting and stone-promoting factors. A high intake of calcium, phosphorus, and ascorbic acid, a low urinary citrate/calcium ratio, a high urinary calcium/creatinine ratio, immaturity, and medication to prevent or treat chronic lung disease with hypercalciuric side effects appear to contribute to the high incidence of NC in preterm neonates.

Topics: Ascorbic Acid; Birth Weight; Calcium; Chronic Disease; Citrates; Creatinine; Gestational Age; Humans; Infant Food; Infant Nutritional Physiological Phenomena; Infant, Newborn; Infant, Premature; Lung Diseases; Nephrocalcinosis; Phosphorus; Prospective Studies; Ultrasonography; Urine

Specialized "nutritional insurance" supplementation may reduce the risk of many important complications of long-term corticosteroid treatment. Supplementation with calcium, fluoride, activated vitamin D metabolites, and GTF, should help prevent osteoporosis. GTF, vitamin C, zinc and fluoride might help offset the inhibitory effect of corticosteroids on fibroblast and osteoblast function. Diabetic, hyperlipidemic and protein-losing effects might be compensated with supplementary GTF. Antioxidant nutrients could support humoral immunity and neutrophil function, while complementing the anti-inflammatory actions of corticosteroids. Supplementary magnesium could reduce the risk of nephrocalcinosis and nephrolithiasis.

Topics: Adrenal Cortex Hormones; Amino Acids; Ascorbic Acid; Chromium; Diabetes Mellitus; Double-Blind Method; Fluorides; Food, Fortified; Humans; Hydroxycholecalciferols; Hyperlipidemias; Immunologic Deficiency Syndromes; Nephrocalcinosis; Nicotinic Acids; Nutritional Requirements; Osteoporosis; Selenium; Silicon