Mohammad Khalid Khan Niazi  ( Department of Nephro-Urology, Jinnah Postgraduate Medical Centre, Karachi. )
Azjza Khanum  ( Department of Biochemistry, University of Karachi. )
Masood A. Sheikh  ( Department of Nephro-Urology, Jinnah Postgraduate Medical Centre, Karachi. )
Syed Ali Jaffer Naqvi  ( Department of Nephro-Urology, Jinnah Postgraduate Medical Centre, Karachi. )

Serum 25-OH-Vitamin D3 , Phosphorus, Calcium, 24 hours Urinary Calcium and phosphorus were measured in 10 patients with calculi and 7 normal subjects. No difference in concentration of serum 25-OH-Vitamin D3, Calcium, phosphorus, 24 hours urinary calcium and phosphorus was found between stone formers and normal subjects (JPMA 37 : 194, 1987).

Serum and urinary parameters have been measured in the past in patients suffering from stone disease in an attempt to correlate these with stone formation.^1,11 Among these serum Vitamin D3 calcium, phosphorus, urinary volume, urinary calcium and phosphorus have been studied. Some investigations have shown high levels of urinary calcium in patients with calculi compared to normal subjects,^4,6,9 whereas others have shown no correlation. ¹³ Gray et al⁴ found that serum phosphorus and 25-OH-Vitamin D3 were signi­ficantly lower in stone formers than in normal controls. In other studies serum 25-OH-Vitamin D3 levels were higher in patients with hypercal­ciuric calculi than in those with normocalciuric calculi patients. ^2,8 This study was performed to evaluate 25-OH-Vitamin D3 levels in patients with normocalciuric calculi in our population.

Seven normal subjects with no past history of urinary stone disease and ten patients with renal calculi were studied.
History and physical examination were recorded in all the cases. Investigations included a complete haematological and biochemical pro­file, x-rays of kidney, ureter and urinary bladder (KUB) or intravenous pyelography (WP). Fasting serum 25-OH-Vitamin D3 calcium and phos­phorus were measured. 24 hour urine samples were collected for calcium and phosphorus. Phosphorus was determined by the method of Delsal et al¹² calcium by Bio-Merieux Kit Cat. No (61041) and 25-OH-Vitamin D3, by Euro-Diagnostics Kit (Code No. B. Vit. 1) using beta-counter.

The average age of normi controls was 26 years. Biochemical profile was normal. Radio­logical examination was negative for calculi.
The mean age of patients with calculi was³⁴ years. Symptoms included haematuria, dysuria and lumbar pain in. majority of patients. Radiological examination showed renal calculi in all patients. Levels of serum 25-OH-Vitamin D3 and serum and urinary calcium and phosphorus are shown in Table-I.

There was no significant difference in values between patients and normal controls.

Apart from low volume there may be other changes in urinary composition which increase the risk of developing calculus disease. When British troops moved from England to Aden they doubled their urinary calcium excretion.¹³ Increased exposure to ultraviolet rays resulting in increase in Vitamin D3 production could have consequently resulted in higher absorption of calcium from diet and its excretion in urine. The seasonal incidence of urolithiasis observed in hot countries may also be due to this mech­anism¹³. Of all stone fonning substances, calcium oxalate and calcium phosphate salts are potentially the most insoluble under the ionic conditions present in urine. The saturation of urine with these salts, particularly calcium oxalate, approxi­mates the point of spontaneous precipitation even in normal urine, probably indicating these salts as the commonest constituents of urinary stones.
However, our study of the different levels of calcium, phosphorus and 25-OH-Vitamin D3 in serum and also urinary calcium and phosphorus revealed no significant difference between normal subjects and patients with calculi. 25-OH-Vita-min D3 levels were normal in both groups. Other studies^2,8 have conveyed similar results, (e.g) Baggio et al and Ryall et al^1,3 Coen et a1⁸ also observed that although 25-OH-Vitamin D3 levels were higher in hypercalciuric stone formers, yet normal in patient with normocalciuric calculi.

1. Baggio, B., Gainbaro, G., Favaro, S. and Boisatti, A. Prevalence of hyperoxaluria in idiopathic calcium oxalate kidney stone disease. Nephron, 1983; 35:11.
2. Inkeri, E., Liisa, KS., Liisa, K.A. and Risto, P. Seasonal variation of urinary calcium and oxalate excretion, serum 25-Hydroxy D3 and albumin Urol. Nephrol., 1981; 17:121. level in relation to stone formation. Fortschr.
3. Ryall, RI. and Marshall, V.R. The Value of 24-hour urine analysis in the assessment of stone­formers attending a general hospital outpatient clinic. Br. J. Urol., 1983;55:1.
4. Gray, R.W., Wilz, D.R., Caldas, A.E. and Lemann, J. Jr. The importance of phosphate in regulating plasma 1,25- (OH)2— Vitamin D levels in humans; studies in healthy subjects, in calcium-stone formers and in patients with primary hyper­parathyroidism. J. Clin Endocrinol. Metab., 1977; 45:299.
5. Welshman, S.G. and McGeown, M.G. The relation­ship of the urinary cations, calcium, magnesium, sodium and potassium in patients with renal calculi. Br. J. Urol., 1975;47:237.
6. Hodgkinson, A. Relation between oxalic acid, calcium, magnesium and creatinine excretion in normal men and male patients with calcium oxalate kidney stone. Chin. Sci., 1974; 46:257.
7. Ljunghall, S. and Waern, U. Urinary electrolytes in renal stone-formers and healthy subjects. A population study of 60-year — old men. Scandina­vian Urol. Nephrol., 1976; 41 (SuppL) : 55.
8. Coen, J.J., Jongen, MJ.M., Vander Vijgh, WJ.F., Lips, P. and Van Ginkel, F.C. Vitamin D status in urinary calcium stone formation. Arch. Intern. Med., 1985; 145:681.
9. Bulusu, L., Hodgkinson, A., Nordin, B.E.C. and Peacock, M. Urinary excretion of calcium and creatinine in relation to age and body weight in normal subjects and patients with renal calculus. Chin. Sci., 1970; 38:601.
10. Evans, R.A., Forbes, M.A., Sutton, R.A.L. and Watson, L. Urinary excretion of Calcium and magnesium in patients with calcium-containing renal stones. Lancet, 1967; 2:958.
11. Tiselius, H.G., Almgard, L.E., Larsson, L. and Sorbo, B. A biochemical basis for grouping of patients with urolithiasis. European Urol., 1978; 4: 241.
12. Wootton, I.D.P. and Freeman, H. Microanalysis in medical biochemistry by Earl J. King: 6th ed. Edinburgh, Churchill Livingstone, 1982, p. 59.
13. Robertson, W.G. Urolithiasis; epidemiology and pathologenesis, in tropical urology and renal disease. Edited by I. Husain, Edinburgh, Churchill Livingstone, 1984, p. 145, 153.