Objective: To report our experience with the endourological treatment of renal matrix stones, an infrequent form of urinary calculi whose diagnosis and treatment are often difficult. Methods: From 1990 to 2010 we treated 9 female patients with matrix calculi using the endourological approach; 4 presented with renal colics, 3 with symptomatic urinary tract infection and 2 with asymptomatic bacteriuria. Six patients underwent percutaneous lithotripsy and 3 retrograde intrarenal surgery as first-line therapy. Three cases needed a multidisciplinary approach. Results: The six percutaneous procedures were successful after a single session, while the retrograde approach required multiple treatments; a single case needed a shock wave session to complete the fragmentation, in another one a percutaneous lithotripsy was necessary after the first procedure, and a third case needed multidisciplinary treatment. Conclusions: Percutaneous lithotripsy has been confirmed as the first option for matrix stones. The retrograde approach - by confirming the suspected diagnosis and being minimally invasive - may be employed to treat either lower-size stones or stones at high risk of recurrence.

1.
Gage H, Beal HW: Fibrinous calculi in the kidney. Ann Surg 1908;43:378-387.
[PubMed]
2.
Allen TD, Spence HM: Matrix stones. J Urol 1966;95:284-290.
[PubMed]
3.
Stoller ML, Gupta M, Bolton D, Irby PB: Clinical correlates of the gross, radiographic, and histologic features of urinary matrix calculi. J Endourol 1994;8:335-340.
[PubMed]
4.
Bani-Hani AH, Segura JW, Leroy AJ: Urinary matrix calculi: our experience at a single institution. J Urol 2005;173:120-123.
[PubMed]
5.
Shah HN, Kharodawala S, Sodha HS, Khandkar AA, Hegde SS, Bansal MB: The management of renal matrix calculi: a single-centre experience over 5 years. BJU Int 2009;103:810-814.
[PubMed]
6.
Boyce WH, Garvey FK: The amount and nature of the organic matrix in urinary calculi: a review. J Urol 1956;76:213-227.
[PubMed]
7.
Bommer J, Ritz E, Tschöpe W, Waldherr R, Gebhardt M: Urinary matrix calculi consisting of microfibrillar protein in patients on maintenance hemodialysis. Kidney Int 1979;16:722-728.
[PubMed]
8.
Boyce WH, King JS Jr: Crystal-matrix interrelations in calculi. J Urol 1959;81:351-365.
[PubMed]
9.
Vermeulen CW, Lyon ES, Gill WB: Artificial urinary concretions. Invest Urol 1964;12:370-374.
[PubMed]
10.
Matthews LA, Spirnak JP: A matrix calculus causing bilateral ureteral obstruction and acute renal failure. J Urol 1995;154:1125-1126.
[PubMed]
11.
Singh H, Pandey S, Dorairajan LN, Kumar S: Acute renal failure due to bilateral matrix renal calculi - a diagnostic dilemma. Int Urol Nephrol 2001;33:311-313.
[PubMed]
12.
Zwirewich CV, Buckley AR, Kidney MR, Sullivan LD, Rowley VA: Renal matrix calculus. Sonographic appearance. J Ultrasound Med 1990;9:61-64.
[PubMed]
13.
Kim SH, Lee SE, Park IA: Case report. CT and US features of renal matrix stones with calcified center. J Comput Assist Tomogr 1996;20:404-406.
[PubMed]
14.
Liu CC, Li CC, Shih MC, Chou YH, Huang CH: Matrix stones. J Comput Assist Tomogr 2003;27:810-813.
[PubMed]
15.
Anjum MI, Palmer JH: Stone matrix clearance from the pelvicalyceal system using a bottle-brush. Br J Urol 1996;78:460-463.
[PubMed]
16.
Beltrami P, Ruggera L, Gigli F, Aloisi A, Zattoni F: La calcolosi molle e le potenzialità del trattamento endourologico. GTND 2009;21:3-6.
17.
Rowley MW, Faerber GJ, Wolf JS Jr: The University of Michigan experience with percutaneous nephrostolithotomy for urinary matrix calculi. Urology 2008;72:61-64.
[PubMed]
18.
Chan CH, El-Hakim A, Andonian S: Renal matrix stone managed by ureteroscopic holmium laser lithotripsy. Can J Urol 2010;17:5127-5130.
[PubMed]
19.
Wall I, Tiselius HG: Long-term acidification of urine in patients treated for infected renal stones. Urol Int 1990;45:336-341.
[PubMed]
20.
Miwa S, Yamamoto H, Sugata T: Antibiotics therapy was effective in preventing bilateral staghorn renal matrix stones. Urol Res 2011;39:69-72.
[PubMed]
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