Akash Chitrakar, Anil Shrestha, Baikuntha Adhikari, Olivier Traxer
Metabolic abnormalities and Randall's plaque were common findings among patients with nephrolithiasis. Elevated urinary oxalate and uric acid levels and younger age of patients were found to be associated with increased severity of Randall's plaque.
PURPOSE: To evaluate the presence of Randall's plaque and its severity in patients with nephrolithiasis and to correlate it with demographic characteristics, metabolic parameters and stone analysis.
METHODS: Consecutive patients undergoing retrograde intrarenal surgery (RIRS) who met study criteria were prospectively enrolled. Demographic characteristics and twenty-four-hour urinalysis were collected. Renal papillae were evaluated for presence of Randall's plaque and its severity graded according to Traxer grading. A fragment of stone was retrieved and analyzed using Fourier Transform Infrared (FTIR) spectroscopy. Correlations of demographic characteristics, metabolic parameters and stone analysis with severity of Randall's plaque were evaluated. A p-value of less than 0.05 was considered as statistically significant.
RESULTS: A total of 108 patients were included in final analysis. Metabolic abnormality was seen in 68.5% of patients with most common abnormality being hypocitraturia (61.1%). Intraoperatively, a total of 839 papillae were observed with mean of 7.77 papillae per patient. Randall's plaque was identified in 66.1% of evaluable papillae and 88.9% of patients had at least one papilla affected by Randall's plaque. Most common severity of plaque was Grade 1 seen in 50.9% of papillae. Majority of stones were calcium oxalate (94.4%). Higher Traxer grade was found to be associated with younger age of patients, elevated urine oxalate and uric acid levels and calcium oxalate stones.
CONCLUSION: Metabolic abnormalities and Randall's plaque were common findings among patients with nephrolithiasis. Elevated urinary oxalate and uric acid levels and younger age of patients were found to be associated with increased severity of Randall's plaque.