Archivio Italiano di Urologia e Andrologia

Theobromine for treatment of uric acid stones and other diseases

2024-10-21T21:24:34+00:00

Theobromine (or 3,7-dimethylxanthine) is a natural alkaloid present in cocoa plant and its derivatives, such as chocolate. About 20% of ingested theobromine is excreted unchanged in the urine. Theobromine also derived from caffeine that is metabolized into theobromine by 12%. The primary metabolites of theobromine are 3-methylxantine, 7-methylxantine, 7-methyluric acid and 3,7-dimethyluric acid. Theobromine has an inhibitory activity of uric acid crystallization, because it has a structural pattern very similar to uric acid and can substitute uric acid molecules in the corresponding uric acid crystals, making them longer and thinner and decreasing their growth rate. Theobromine also favors the dissolution of crystals by decreasing supersaturation of uric acid by forming aggregates with uric acid through hydrogen bonds and aromatic stacking interactions (-stacking bonds) increasing urinary solubility of uric acid. Theobromine can be used for uric acid stone dissolution in combination with alkalinization to reduce the dose of citrate, thus preventing excessive alkalinization and the risk of formation of sodium urate crystals. Theobromine could also be used to treat patient with xanthine stones that cannot be dissolved by alkalinization because the solubility of xanthine is relatively independent of urinary pH. A metabolite of theobromine, 7-methylxanthine, has the potential to be used for the prevention of the formation of sodium urate crystals in the synovial fluid of gouty patients.

Should patients with encrusted JJ stents involving the proximal/renal loop undergo primarily endoscopic combined intrarenal surgery?

2024-11-11T09:43:34+00:00

Background: Ureteral stents are one of the most used devices in Urology, allowing drainage of the upper urinary system, and can be used either in elective or emergency procedures. However, as a foreign body inside the urinary system, they are subject to encrustation. Encrustation is one of the burdens seen with double-J stents and, to date, there is no consensus about its best management. This study aims to prove that Endoscopic Combined Intra-Renal Surgery (ECIRS) is the best choice when there’s an encrusted proximal loop of a ureteral stent.
Methods: The authors conducted a retrospective cohort study of patients with an encrusted proximal loop of the ureteral stent who underwent surgery at a single center, comparing ECIRS with other procedures.
Results: Between July 2011 and June of 2024, 33 patients (18 females and 15 males) were submitted to surgery. The median indwelling time of the stent was 11 (8-19) months and a stentfree rate of 100% was achieved. The authors demonstrated a significant stone-free rate of 61.1% following ECIRS compared to merely 20% with other procedures (p = 0.023). Notably, while the complication rate was low across all procedures, the ECIRS group exhibited fewer complications (5.6%) than those undergoing alternate techniques (13.3%), though this difference was not statistically significant (p = 0.439).
Conclusions: Our study advocates for ECIRS as the preferred initial treatment for encrusted proximal ureteral stents, as it facilitates superior stone clearance, minimizes complications, and maintains comparable operative efficiency. This research contributes valuable insights into the management of challenging cases involving encrusted ureteral stents, calling for future studies to further validate these findings.

Multiparametric MRI targeted prostate biopsy: When omit systematic biopsy?

2024-11-11T09:43:37+00:00

Introduction: To evaluate the detection rate for prostate cancer (PCa) performing multiparametric magnetic resonance imaging (mpMRI) fusion targeted biopsy (TPBx) combined only with ipsilateral systematic prostate biopsy (SPBx).
Materials and Methods: From January 2023 to December 2023, 495 men with clinical suspicion of PCa underwent transperineal SPBx plus TPBx in the presence of PI-RADS score lesions ≥ 3.
Results: In 250/495 men (50.5%) a PCa was found, while 36/250 (14.4%) men had negative mpMRI. In comparison to TPBx, SPBx diagnosed a higher number of indolent PCa, 38.5 vs. 5.8%, respectively; conversely, SPBx demonstrated a higher detection rate for clinically significant PCa (97.3 vs. 85.4%) in the presence of ISUP Grade Group 2 (GG2). In details, rates were higher in the presence of GG2 (100 vs. 76%), GG3 (85.7 vs. 75.8%) and GG4 (100 vs. 86.4%) tumors. However, in GG5, both SPBx and TPBx diagnosed 100% of csPCa. Furthermore, 89.4% of the cases showed csPCa on the negative mpMRI side.
Conclusions: SPBx combined with TPBx maximized csPCa diagnosis; the use of reduced biopsy scheme limited to ipsilateral side of mpMRI lesion plus TPBx missed 11.6% csPCa. Only in the presence of PI-RADS score 5 SPBx and TPBx diagnosed both 100% of csPCa.