Evaluation of free amino acids in plasma and 24 - hour urine samples of control subjects and patients with calcium urolithiasis

To evaluate free amino acid levels in Plasma and 24-h urine samples of control subjects and patients with calcium urolithiasis. Design: Amino acid analysis of Plasma and 24-hour urine samples. Setting: Department of surgery, Combined Military Hospital, Hyderabad and Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro. Subject All calcium stone formers and controls are hospital in-patients. Main outcome measures: To demonstrate differences between calcium stone formers and non-stone forming controls with respect to their plasma and 24-hour urine amino acid profiles. Plasma levels of aspartic acid, glutamic acid, glycine, histidine, hydroxyproline, isoleucine, leucine, methionine, phenylalanine, proline, serine, threonine, tyrosine and valine were significantly higher [p <0.01] in calcium stone patients than in control subjects. The urinary excretions of aspartic acid, cystine, glycine, hydroxyproline, lysine, phenylalanine, serine, threonine, lyrosine and valine were significantly higher [p < 0.01] and of alanine lower [p <0.01] in patients compared to the corresponding value in control subjects. The data presented in this paper indicates some striking differences in the levels of many amino acids as indicated by mean plasma concentrations and daily excretions from urolithic patients and control subjects

Hypocitraturia associated with phosphaturia and hyperoxaluria as major risk factors in male recurrent calcium stone cases

To identify urinary and pre-urinary risk factors for recurrent calcium stone disease in male adults of Hyderabad and adjoining areas. Design: Biochemical analysis of serum and 24-hours urine samples. Setting: Surgical Unit- I, Liaquat Medical College Hospital and Department of Biochemistry, University of Sindh, Jamsharo. Subjects: Male adults involving 39 patients with recurrent calcium stone disease including 18 with positive family history and 36 normal controls. Main outcome measures: Risk factors as assessed from serum and urine levels of various lithogenic and inhibitory substancse. Hyperphosphatemia was observed in about 85% patients. The daily urinary excertion of oxalate and phosphate was significantly [P<0.01] higher and the daily urinary excretion of citrate and sodium was lower in stone formers than in controls. Biochemical abnormalities were deleted in 29 patients [74.4%], including hypocitraturia [25.6%] hyperoxaluria [23.1%] hyperuricosuria [20.2%] and hypercalciuria [5.1%]. Conclusions: Hypocitraturia associated with phosphaturia and hyperoxaluria might be the major causative factors predisposing to recurrent calcium stone disease in male adults of Hyderabad and adjoining areas