Hyperoxaluria in urolithiasis and Cystone Therapy

Twenty-seven patients with urolithiasis and twenty-three normal subjects comprised this study. They were kept on an oxalate-free diet for 48 hr prior to and during urine collection to rule out any dietary influence on oxaluria. 24-hr urine samples were collected for oxalic acid estimation. After this all the patients received Cystone, 2 tabs. t.i.d. for 8 weeks. The above procedures were repeated at 4 and 8 weeks. After Cystone therapy a marked reduction in oxaluria was noted in those with high initial values. This is of significance since it is known that hyperoxaluria is an important aetiological factor for urolithiasis. INTRODUCTION Urolithaisis constitutes one of the commonest afflictions requiring surgical intervention in our country and by conservative estimates there are about 5-7 million patients suffering from urinary calculus disease in India. It is not only the high prevalence which requires early attention, but rather the more problematic, high rate of recurrence after surgical removal. It is for these reasons that the Indian Council of Medical Research has classified this disease as one of the refractory diseases and stressed that efficient efforts should be made to find out the cause/s of the disease and to search for suitable drug/s for its cure (Satyawati, 1982). High prevalence and recurrence rates in Rajasthan have been reported in past studies (Pendse et al, 1982 and Singh et al, 1983). Finalyson (1974) has clearly stated that changes in urinary oxalate concentration are 15 times more potent than changes in calcium concentration in altering the saturation of urine with calcium oxalate. The role of hyperoxaluria in stone formation is further supported by the studies of Robertson et al (1979) and Thomas et al (1979). In our country several indigenous drugs for the treatment of urinary calculus disease have been in vogue since ancient times [Charak (600 BC) and Sushruta (1000 BC)]. The various herbal drugs used include Didymocarpus pedicellata (Patharphor), Dolichos biflorus (Kulath), Rubia cordifolia (Manjit), Crataeva nurvala (Varuna) and Tamarindus indica (Tamarind). Deshpande et al (1982) have extensively investigated the role of Varuna in urinary disorders and have found it beneficial in altering urinary chemistry. Cystone, manufactured by The Himalaya Drug Co., is a formulation of such herbal drugs. Dandia et al (1975-76) concluded from their study on rats and dogs that Cystone provides some protection against the growth and recurrence of urinary stones. Therefore this study was carried out to compare the oxalic acid excretion of stone formers with those of normal subjects in the local population and to evaluate the effect of eight weeks’ Cystone therapy on oxaluria. MATERIAL AND METHODS Twenty-seven patients of urolithiasis and twenty-three normal subjects form the basis of this study. The normal subjects were selected from the medical students and staff members of the R.N.T. Medical College, Udaipur, while the stone formers were from the surgical wards of the General Hospital of the said Medical College. The latter were selected only after confirmation of their diagnosis by radiological examination. All the stone formers thus had a stone in their urinary tract. Both the normal subjects and patients were put on a controlled diet avoiding oxalate-rich foods for 48 hours prior to and during urine collection, to rule out any dietary influence on oxaluria. 24-hour urine samples were collected (from 8.00 a.m. to 8.00 a.m.) in a 2.5 litre capacity bottle containing 10 ml of conc. HCl as preservative. Quantitative estimation of oxalic acid in urine was done by the method of Hodgkinson and Williams (1972). Following this, all the patients were put on Cystone, 2 tablets t.i.d. for eight weeks. After four weeks and eight weeks, the same procedures were repeated for collection and analysis of the urine samples. OBSERVATIONS AND DISCUSSION Table I indicates that oxalic acid excretion in stone formers is significantly higher as compared to the normal subjects. Therefore, hyperoxaluria is an important aetiological factor of urolithiasis in the local population of the Udaipur region. Table I: 24-hour oxaluria (mg) in normal subjects and stone formers Normal Subjects Stone Formers 1. Range 7.8 38.9 10.6 117.0 2. Mean 21.51 41.43 3. Standard deviation ± 8.80 ± 29.65 4. Standard error of mean 1.83 5.71 Table II shows that in stone formers, oxaluria is gradually reduced after Cystone therapy, the mean values being similar to those of normal persons. Table II: 24-hour oxaluria in stone formers after Cystone therapy After 4 weeks After 8 weeks 1. Range 4.4 135.2 2.2 79.8 2. Mean 34.51 25.46 3. Standard deviation ± 32.23 ± 20.26 4. Standard error of mean 6.21 5.62 t = 0.82 1.99 df = 52 38 p>0.05 p>0.05 Table III shows a marked decrease in oxaluria in six patients who had very high initial values. After 8 weeks of treatment with Cystone, oxaluria was similar to that in normal persons Table III: 24-hour oxaluria in 6 patients with initially high oxaluria, after Cystone therapy Patient Initial After 4 weeks After 8 weeks Ra 86.3 56.8 25.8 Ja 58.5 51.6 20.8 Pu 75.2 18.9 15.5 Da 46.4 12.2 24.3 Di 104.5 135.2 28.3 Bd 55.1 40.6 26.7 Table IV depicts the statistical evaluation of the 6 hyperoxaluric stone formers, following Cystone therapy. Table IV: Statistical evaluation of Cystone therapy in the 6 hyperoxaluric stone formers Initial After 4 weeks After 8 weeks 1. Range 46.4 104.5 12.2 135.2 15.5 28.3 2. Mean 70.966 52.58 23.57 3. Standard deviation ± 19.97 ± 40.32 ± 4.29 4. Standard error of mean 8.16 16.47 1.75 t = 0.9137 t = 3.8132 df = 10 df = 10 p>0.05 p>0.01 Significant even at confidence level of 1%. Statistical calculation on the second side is between the initial and follow-up values after eight weeks. CONCLUSIONIt can be concluded from the present study that hyperoxaluria is certainly an important aetiologicalfactor for urolithiasis. Cystone therapy for eight weeks corrects this abnormality to a great extent -more so in severe hyperoxaluric patients. Patients subjected to surgical intervention for urolithiasismay also be treated with Cystone to lower the recurrence rate. REFERENCES1. Finlayson, B., Renal lithiasis in review, Urol Clin. N. Am. (1974): 1, 181. 2. Hodgkinson, A. and Williams, A., An improved calorimetric procedure for urine oxalates,Clin. Chem. Acta. (1972): 36, 127. 3. Pendse, A.K. et al. XXIII International Biennial Congress, International College ofSurgeons Bull. (1982): 188. 4. Robertson, W.G. et al. The significance of mild hyperoxaluria in calcium stone formation.In: Oxalate in human biochemistry and clinical pathology (1979), p. 173, The WellcomeFoundation Ltd., London. 5. Satyawati, G.V. some traditional medical systems and practices of global importance, Ind. J.Med. Res. (1982): 76, 1 (Dec. Supp.). 6. Singh, P.P. et al, Blood and urine chemistry of stone formers in local population andevaluation of Cystone treatment, Ind. Drugs (1983): 20, No. 7, 264. 7. Thomas, J. et al. Urinary oxalate in human biochemistry and pathology (1979), p. 186, TheWellcome Foundation Ltd., London. 8. W.H.O. Tech. Rep. Ser. (1978): 622. The promotion and development of traditionalmedicine.