Semirigid ureteroscopy is effective, with a 90% stone-free rate and efficacy quotient. Most complications are low grade and self-limiting. Our results confirm that prolonged operative time is an independent predictor of complications, and should be considered when choosing and performing the treatment modality.

absence of MVI. The prognostic value of all the variables assessed was then evaluated, and correlated with the usual prognostic variables and cancer-specific survival. RESULTSUnivariate analysis of cancer-specific survival showed that tumour stage ( P < 0.001), tumour size ( P = 0.005), metastasis, MVI, Ki-67 LI, CD44H LI and VEGF expression (all P < 0.001) were predictors of tumour-related death. There was a statistical correlation between CD44H LI and each of Ki-67 LI ( r = 0.61), expression level of VEGF ( r = 0.72) and presence of MVI ( r = 0.71). Independent predictors of cancer-specific survival in a multivariate analysis were: in all patients with RCC, the MVI ( P = 0.003) and VEGF expression ( P = 0.01); in those with no metastases, MVI ( P = 0.01); in patients with no MVI, VEGF ( P = 0.04); and in patients with MVI, Ki-67 LI ( P = 0.003). No independent predictor was identified in patient with metastases.

Percutaneous nephrolithotomy is the treatment of choice for most renal calculi in children. The technique is effective and safe in children, with a high success rate and a low rate of major complications. The significant factors identified should be considered by clinicians to decrease associated complication rates.

In 174 cases of genitourinary tuberculosis diagnosed and treated in our clinic we evaluated, retrospectively, age and sex distributions, symptoms, physical and laboratory findings, primary focus, surgical and medical treatments. Flank pain and non-specific urinary complaints, e.g. dysuria, were the major symptoms. Although some authors prefer short-term medical therapy for the treatment of genitourinary tuberculosis, the relapse rate in our series after 12 months of therapy was 19% and we therefore suggest that therapy should be continued for at least 12 months. The poor nutritional status and social conditions characteristic of subjects from our region may, however, have influenced this high relapse rate.

Taq I t allele of the VDR gene may be a risk factor for severe urolithiasis and recurrent stone disease.