Low-energy high-frequency Ho-YAG lithotripsy: is RIRS going forward? A case-control study.

Retrograde Intra-Renal Surgery (RIRS) plays a primary role in renal stone treatment context. Energy, frequency and width of laser impulse can be modulated by surgeons to achieve better outcomes. In our study, patients with single renal stone sized 10-20 mm were retrospectively divided into two groups. Patients of Group 1 underwent RIRS with Low-Energy (LE) High-Frequency (HF) settings using Lumenis® 120-W high-power Ho:YAG laser. Patients of Group 2 (control) underwent RIRS using "standard" settings by means of Sphinx® Jr 30 W Ho:YAG system. Follow-up was conducted with a CT scan at 3 months after RIRS in both groups. Procedure success was defined as stone-free or presence of ≤ 4 mm fragments (Clinical Insignificant Residual Fragments-CIRF). A total number of 199 patients were included: 86 LE/HF RIRS (Group 1) vs 113 "conventional" RIRS (Group 2). Mean operative time was 56.6 (± 19.4) min in Group 1 vs 65.2 (± 25.2) min in Group 2 (p = 0.01). Mean hospitalization time was 2.5 ± 1.7 days for Group 1 vs 2.9 ± 3.2 days for Group 2 (p = 0.2). Peri-operative complications were counted: eight in Group 1 and 11 in Group 2 (p > 0.05). At 3-month control, stone-free rate was 69% (59/86 patients) in Group 1 vs 65% (73/113 patients) in Group 2 (p = 0.6). Success rate was 93% (80/86) in Group 1 in comparison to 82% (93/113) in Group 2 (p = 0.03). In conclusion, LE/HF RIRS seems to be a feasible and effective technique with a reduction of operative time and optimal results in terms of "stone-free" and "success" rates. Further studies are needed to ensure the validity of our results and to give evidence-based statements.

[Primary hyperoxaluria and pregnancy]. / L'iperossaluria primaria e gravidanza.

A rare case of pregnancy in a patient with primary hyperoxaluria type 1 is reported offering a clinical contribution for the prognostic study of a natural event such as the pregnancy on these patients. It is underlined how epicriticity of the hepatorenal system is remarkably altered during the last weeks of pregnancy with a great increase of calciuria and proteinuria with a risk of life for the patient and the newborn. In fact, during the 36rd week a caesarean section was performed due to gestosis. Moreover, the deterioration of kidney functionality doesn't decrease during post partum. Therefore, it would be advisable inform these patients about the risk of pregnancy.