oxalates and Osteoporosis

Short bowel syndrome (SBS) occurs in patients who have had extensive resection. The primary physiologic consequence is malabsorption, resulting in fluid and electrolyte abnormalities and malnutrition. Nutrient digestion, absorption, and assimilation may also be diminished by disturbances in the production of bile acids and digestive enzymes. Small bowel dilation, dysmotility, loss of ileocecal valve, and anatomical changes combined with acid suppression and antimotility drugs increase the risk of small intestinal bacterial overgrowth, further contributing to malabsorption. Metabolic changes that occur in SBS due to loss of colonic regulation of gastric and small bowel function can also lead to depletion of calcium, magnesium, and vitamin D, resulting in demineralization of bone and the eventual development of bone disease. Persistent inflammation, steroid use, parenteral nutrition, chronic metabolic acidosis, and renal insufficiency may exacerbate the problem and contribute to the development of osteoporosis. Multiple factors increase the risk of nephrolithiasis in SBS. In the setting of fat malabsorption, increased free fatty acids are available to bind to calcium, resulting in an increased concentration of unbound oxalate, which is readily absorbed across the colonic mucosa where it travels to the kidney. In addition, there is an increase in colonic permeability to oxalate stemming from the effects of unabsorbed bile salts. The risk of nephrolithiasis is compounded by volume depletion, metabolic acidosis, and hypomagnesemia, resulting in a decrease in renal perfusion, urine output, pH, and citrate excretion. This review examines the causes and treatments of small intestinal bacterial overgrowth, bone demineralization, and nephrolithiasis in SBS.

Topics: Bacteria; Bone and Bones; Bone Density; Calcium; Colon; Humans; Intestinal Mucosa; Intestine, Small; Kidney; Kidney Calculi; Osteoporosis; Oxalates; Short Bowel Syndrome

Whereas the etiology of urinary calculi and their metabolic exploration should be known, it appears unreasonable to conduct exhaustive metabolic explorations in all patients, therapy being usually symptomatic and based on advice on hygiene and diet. However, etiologic diagnosis is essential in a small number of cases: those which could benefit from effective preventive and curative measures and for which morbidity is elevated: cystinuria, hyperparathyroidism, uric acid calculi, patients at high developmental risks. It is possible, by simple, low cost means to select 95% of these patients. After a theoretical study of the distribution and lithiasic etiology, a practical conduct is proposed which takes into account the cost-effective ratio.

Topics: Acidosis; Calcium; Citrates; Cystinuria; Humans; Hypercalcemia; Hyperparathyroidism; Intestinal Absorption; Kidney Calices; Osteoporosis; Oxalates; Sarcoidosis; Uric Acid; Urinary Calculi

Topics: Adult; Animals; Bone and Bones; Calcium; Calcium, Dietary; Diet; Dietary Fats; Dietary Proteins; Dihydroxycholecalciferols; Humans; Inositol; Intestinal Absorption; Intestine, Small; Jaw Diseases; Lactose; Magnesium; Male; Nutritional Physiological Phenomena; Nutritional Requirements; Osteoporosis; Oxalates; Phosphorus; Protein Binding; Proteins; Vitamin D

To investigate bone mineral densitometry findings in patients with normocalciuric urinary system stone disease, we compared 150 patients with normocalciuric calcium stone disease (group 1) and 60 subjects of a control group (group 2). The patients were compared according to bone mineral content (BMC), bone area (BA), bone mineral density (BMD), T-score and Z-score values of femur neck, total femur and lumbar spine (L2-L4) by dual energy absorptiometry. We found that 76.6% of the patients in group 1 and 20.0% in group 2 had low BMD; 11.3% of patients in group 1 had osteoporosis and 65.4% had osteopenia. In the control group, there was no osteoporosis, but 20.0% of the subjects had osteopenia. In group 1, there was hyperoxaluria in 26.0% of patients, hypocitraturia in 15.3% of patients, hyperuricosuria in 6.0% of patients, both hypocitraturia and hyperoxaluria in 8.6% of patients in a 24-h urine analysis. Urine analysis was normal in 44.0% of patients. Our results showed a severe loss of bone mass in patients with urinary system normocalciuric calcium stone disease. Thus, the necessary precautions concerning bone mass protection should be taken and the patients should be informed about this issue.

Topics: Absorptiometry, Photon; Adult; Bone Density; Bone Diseases, Metabolic; Calcium; Citrates; Female; Femur; Humans; Lumbar Vertebrae; Male; Middle Aged; Osteoporosis; Oxalates; Recurrence; Urolithiasis

Topics: Acidosis; Amino Acid Metabolism, Inborn Errors; Amino Acids; Child; Child, Preschool; Glutamates; Glycine; Glyoxylates; Humans; Infant; Intelligence; Leucine; Male; Osteoporosis; Oxalates; Psychomotor Disorders; Serine

Topics: Acidosis; Alkalies; Humans; Hyperparathyroidism; Kidney Calculi; Lithiasis; Milk; Nephrolithiasis; Osteoporosis; Oxalates; Sarcoidosis; Urinary Tract Infections; Vitamin D