The CARI guidelines. Kidney stones: metabolic evaluation

An Increase Incidence in Uric Acid Nephrolithiasis: Changing Patterns

INTRODUCTION

Nephrolithiasis is a complex disease affecting all age groups globally. As the causative factors for nephrolithiasis rises significantly, its incidence, prevalence and recurrence continues to baffle clinicians and patients.

AIM

To study the prevalence of different types of renal stones extracted by Percutaneous Nephrolithotomy (PCNL) and open surgical procedures.

MATERIALS AND METHODS

Renal stones from 50 patients were retrieved by Percutaneous Nephrolithotomy (PCNL), Ureterorenoscopy (URS) and open surgical techniques for qualitative tests for detection of calcium, oxalate, uric acid, phosphate, ammonium ion, carbonate, cystine and xanthine.

RESULTS

Three patients had stone removed by open surgery and rest had undergone PCNL. Nine of the stones were pure of calcium oxalate, 9 were of pure uric acid and 32 were mixed stones. Forty one stones had calcium. Among the mixed stones, oxalate was present in 25 samples (39 of total), uric acid was seen in 17 (25 of total stones), phosphate was present in 23 (23 of total) and carbonate was present in 4 stones (4 of total). Only 1 patient had triple phosphate stone. 12 were of staghorn appearance of which 6 were of struvite type, 6 were pure uric acid and remaining were mixed oxalate-phosphate stones.

CONCLUSION

Our study, though in a small number of hospital based patients, found much higher prevalence of uric acid stones and mixed stones than reported by previous hospital based studies in north India (oxalate stones~90%, uric acid~1% and mixed stones~3%). Biochemical analysis of renal stones is warranted in all cases.

Plasma and urinary levels of cytokines in patients with idiopathic hypercalciuria

BACKGROUND

Recent studies suggest that cytokines modulate bone turnover. Idiopathic hypercalciuria (IH) seems to be associated with bone mineral loss. Therefore, the aim of this study was to assess cytokines involved in bone turnover in patients with IH.

METHODS

Plasma and spot-urine levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), transforming growth factor β1 (TGF-β1), and monocyte chemoattractant protein (MCP-1) were measured in 70 children and adolescents with IH and in 37 healthy controls. Patients with IH were subdivided according to their calciuria at the time of sample collection: ≥4 mg/kg/day (persistent IH, n=27) and below 4 mg/kg/day (controlled IH, n=43). Cytokines were determined by enzyme-linked immunoassay.

RESULTS

Plasma and urinary concentrations of IL-1β, IL-6, IL-8, and TNF-α were undetectable in all groups. No differences were found between controlled and persistent hypercalciuria for plasma and urinary levels of MCP-1 and TGF-β1. On the other hand, MCP-1 levels were significantly higher in both subgroups of IH in comparison to healthy controls. Furthermore, urinary MCP-1 levels of IH patients correlated positively with bone mineral content (p=0.013).

CONCLUSION

Although cytokine measurements did not allow the differentiation between persistent and controlled IH, our findings suggest that MCP-1 might play a role in patients with IH.