[Microinfections and kidney lithiasis]. / Microinfecciones y litiasis renal.

OBJECTIVE: The existence of microinfections produced by bacteria of a very small size (nanobacteria) could be a risk factor for stone formation. The results of a study to detect the presence of nanobacteria in calculi are presented. METHODS: 1,000 calculi (excluding struvite calculi) were analyzed by macroscopic and microscopic techniques. RESULTS: Microorganisms were detected in only 5 calculi (0.5%). All these calculi had developed in cavities with low urodynamic efficacy. The microorganisms were located in the center of the calculus and the main component was calcium oxalate monohydrate or uric acid. Ammonium urate/sodium urate were frequently found to be a minor component in the center of the calculus. The only common biochemical urinary alteration observed in these patients was a urinary pH below 5.5; conventional urine cultures were always negative. CONCLUSIONS: Our findings demonstrate that these bacteria can play an important role in the development of calculus by inducing the formation of heterogeneous nucleants of calcium oxalate and uric acid. According to our results, however, this mechanisms is not common and would also be associated to other lithogenic risk factors. It is important to underscore that the majority of patients suffered from stomach ulcers and/or gingivitis which are conditions that could be induced by the same type of microorganisms. Therefore, it can be deduced that similar bacterial factors might be involved in pathologies that have as yet not been related. Further studies are warranted to clearly identify these bacteria.

[Types of kidney calculi. Relationship with urinary biochemistry]. / Tipos de cálculos renales. Relación con la bioquímica urinaria.

OBJECTIVE: To present a simple classification of the most frequent renal calculi that relates each type of calculus with the main possible etiologic factors linked to its formation (mainly urinary biochemical parameters). METHODS: The macro, microstructure and composition of 2,500 renal calculi were studied by appropriate combination of stereoscopic microscopy, IR spectroscopy and scanning electron microscopy + X-ray microanalysis. The information obtained were related with the main urinary biochemical parameters, determined by conventional analytical procedures. RESULTS: Ten main categories of renal stones, covering over 95% of all conceivable calculi, are distinguished based on their composition and structure. Etiologic factors, mainly urinary biochemical parameters, leading to the formation of stone of every category are specified. CONCLUSIONS: From the detailed study of the renal calculus important etiologic factors can be deduced. Such information complements and confirms the urinary biochemical studies. As a consequence, the corresponding treatment can be better established.

[Anuria in HIV+ patients treated with indinavir]. / Anuria en pacientes HIV+ tratados con Indinavir.

OBJECTIVE: Two cases of oliguric acute renal failure in HIV+ patients treated with indinavir are described. METHODS: Patient evaluation included blood analysis, urinalysis, abdominal x-rays, renal US and IVP. RESULTS: Both cases resolved with discontinuation of drug therapy, administration of fluids and urine acidification. CONCLUSIONS: Severe acute renal failure is an uncommon complication in HIV+ patients treated with indinavir. This drug has a great tendency to precipitate in urine. The severity of the crystalluria depends on the drug dose and urinary pH, and can cause tubulointerstitial nephritis and urinary calculi with obstruction of the urinary tract.

[Low-flow priapism associated with systemic lupus erythematosus and nephrotic syndrome]. / Priapismo de bajo flujo asociado a lupus eritematoso sistémico y síndrome nefrótico.

OBJECTIVE: To present a case of priapism associated with systemic lupus erythematosus and nephrotic syndrome. METHODS: A 29-year-old male patient with a history of multiple pathologies consulted at the emergency services with painful priapism of 12 hours' duration. The intracavernosal aspirated blood had a venous appearance. Among the risk factors analyzed, systemic lupus erythematosus and nephrotic syndrome are recognized to cause hypercoagulability, a condition that can lead to low flow priapism. RESULTS: There was no response to lavage-aspiration or intracorporeal administration of an alpha-adrenergic agonist. The high surgical risk of the patient advised against surgery. The priapism gradually diminished until complete remission on the sixth day. The patient has remained without spontaneous erection. CONCLUSION: Systemic lupus erythematosus and nephrotic syndrome can cause low flow priapism. The best treatment is by prevention with adequate antithrombotic prophylaxis.

[Rectorrhage as an unusual extrarenal complication after ESWL]. / Rectorragias como complicación extrarrenal poco habitual tras LEOC.

We report a case of rectorrhage due to an hematoma of sigmoid colon post ESWL in a patient with chronic hepatopathy and right ureteral calculus. We comment the clinic and endoscopical study, as well as the review of literature.

[Biochemical effects of potassium citrate in the treatment of calcium oxalate lithiasis]. / Efectos bioquímicos del citrato potásico en el tratamiento de la litiasis oxalocálcica.

The serum and urinary biochemical changes observed one month and six months after oral potassium citrate therapy (600 mEq/day) in 119 patients with calcium oxalate calculi were compared with those of 16 untreated cases with lithiasis. The patients that received treatment were previously divided into two groups: group A comprised 61 hypocitraturic patients and group B comprised 58 patients with other urinary disorders who were normo or hypocitraturic. The urinary pH increased by approximately half a point in both treated groups. In group A calciuria increased slightly from 180 +/- 8 to 216 +/- 10 mg/24 h but remained within the normal ranges. Creatinuria, oxaluria, uricosuria and diuresis showed no changes. Citraturia increased very significantly in both groups and more markedly in the hypocitraturic group of patients (from 198 +/- 13 to 476 +/- 35 mg/24 h). The LRC (lithogenic risk coefficient = Ca/Cit x Diu) dropped by 50%. The patients tolerated the treatment regimen well; of the 119 treated patients, only 11 abandoned treatment due to GI intolerance.

[Prostatic invasion by lymphoma]. / Invasión prostática por linfoma.

Presentation of a case of prostatic infiltration by malignant lymphoma, discovered through manifestation of simple urinary symptomatology. The paper describes the diagnostic process followed, and includes reproduction of the most interesting findings. The rarity of this disorder and the good response obtained from the alternative chemotherapeutic therapy is emphasized.

[Benign pathology of the urachus in adults: report of two cases]. / Patología benigna del uraco en el adulto: a propósito de dos observaciones.

Two cases of being pathology of urachus in adults are present, the first one correlated to a urachus cyst and the second one to a vesicourachal diverticulum. We believed publication is justified since this pathology is quite uncommon in adult patients.

[Internal urinary derivation using an antegrade approach: indications, technic and results]. / La derivación urinaria interna por vía anterógrada: indicaciones, técnica y resultados.

We report our experience in a group of patients with different pathological conditions and ureteral obstruction in whom placement of a double J stent had been attempted. Insertion of the stent beyond the site of obstruction by the retrograde technique could not be achieved and we therefore used the fluoroscopy-guided percutaneous approach. The indications, techniques and results are discussed.

[Urinary lithiasis composed of silica]. / Litiasis urinaria de silice.

We present a case of urinary silica (silicon dioxide) lithiasis in a patient without a background of medication use justifying the formation of this calculus. We review the literature on this type of lithiasis and comment on some aspects of the metabolism of silica connected with urolithiasis.

[Transitory amaurosis after transurethral resection of the prostate. Apropos of a case]. / Amaurosis transitoria post-R.T.U. de próstata. A propósito de un caso.

A case of transitory amaurosis after T.U.R is presented. This complication differs from the so-called Post-TUR Syndrome. Likewise, the possible physiopathological role of glycine as an inducer of blindness is discussed.