[Hypernephroma at the isthmus of a horseshoe kidney]. / Hipernefroma en el itsmo de riñón en herradura.

Presentation of a case of neoplasia associated to horseshoe kidney (HK). There is a tendency to suffer neoplasia in HK, hypernephroma being the most commonly seen, followed by renal pelvis tumours and Wilms' tumour with a frequency up to 8 times higher than in normal kidneys. This observation suggests that it should be compulsory to carry out cytogenetic studies in order to detect the 11p13 deletion as a possible marker in all children with HK.

[Renal oncocytoma. Presentation of a case]. / Oncocitoma renal. Presentación de un caso.

One case of renal oncocytoma whose diagnosis was established after radical nephrectomy is presented here. The histological heterogeneity of this tumour indicates that the safest treatment is still the radical nephrectomy, at which time diagnosis is most often established. Our case has a special interest as it presented two hepatic lesions suggestive of metastasis.

[Transitional cell carcinoma of the urethra in a male]. / Carcinoma transicional de uretra de un varón.

We present a case of primitive urethral carcinoma in a male. The diagnosis was established with physical exploration when we observed papillomatous formations in the fossa navicularis upon everting the meatus. The interest of this case lies in the rare nature of primitive urethral tumours, in its localization at anterior urethra level, and in its transitional histological strain, as transitional ones are usually located at prostatic and not anterior urethra level as in this case that we submit.

[Wunderlich syndrome: presentation of a case]. / Síndrome de Wunderlich: aportación de un caso.

We present a case of spontaneous renal bleeding due to renal neoplasia. We analyse other causes of Wunderlich's syndrome and, following Kendall, we defend the indication of radical nephrectomy especially of non-filiated etiology in the cases in which other causes have been discounted and the contralateral kidney is sound.

[Ureteroiliac fistula as a complication of ureterorenoscopy]. / Fístula ureteroiliaca como una complicación de ureterorrenoscopia.

Although complications post-URS are scant and can usually be resolved by conservative methods, these however, may be potentially severe as in the present case in whom a ureteroiliac fistula was observed during a URS procedure that had been performed to dilate a post-URS stenosis. Previously, extravasation had also occurred. The post-URS complications are briefly described and discussed.

[Cystic pyeloureteritis. Presentation of 10 cases]. / Pieloureteritis quística. Presentación de 10 casos.

Based on the analysis of 10 cases of cystic pyeloureteritis, a rare entity of benign outcome, the authors suggest that the cysts might be the result of an hyperreactivity of the urothelium to an aggression, and feel that the correction of the etiologic factors might prevent the evolution of Von Brunn's nests.