Original Article Comparison of 24 hours urinary citrate levels in urolithiasis patients and healthy controls

Objective: To identify the difference in urinary citrate excretion between Stone Formers (SF) and Healthy Volunteers (HV) as a metabolic risk factor, that predisposes to urinary stone formation and to compare levels of uri-nary citrate in (HV) with reference values. Methods: The 24 hours urinary citrate was evaluated in 40 patients treated for renal citrate and declared stone free, and 40 age matched healthy adults taken as controls. Both the groups had a similar living environment, extrinsic factors, diet and similar genetic descent. Results: There was no significant difference in urinary citrate excretion level among stone formers (mean 262 SD 197) and normal volunteer subjects (mean 269 SD 140). Using the previously defined normal values (200) of uri-nary citrate in the local population, 55 % of stone patients in our study group were hypocitric. While using the same value, 45 % of our normal volunteers were also hypocitric. If 320 was taken as normal limit, 70 % of the patient's population and 72 % of controls were hypocitric. The prevalence of hypocitraturia was similar in the age matched adult groups. Conclusion: Certain intrinsic factors in our local subjects may account for the high prevalence of urolithiasis than in western population. Although the urinary citrate excretion of stone patients is similar to normal volunteers, uni-formly low urinary citrate excretion may be a feature as a nation and not a predisposing factor for the lithogene-sis. This supports the view that there may be more often prominent influences in stone formers possibly of genet-ic origin (JPMA 55:371;2005)