[Metabolic study. How to make it accessible, useful and generalized.] / Estudio metabólico. Cómo hacerlo accesible, útil y generalizado.

Risk factors should be evaluated in all patients with urinary lithiasis. The kind of evaluation, simplified or extended, depends on stone composition and, in patients with calcium lithiasis, on the clinical presentation. These studies are done in an outpatient regimen, are easy to perform and accessible for most laboratories. Patients with uric acid, infectious and cystine stones only require a selective more abbreviated evaluation. In calcium lithiasis we perform an extended metabolic evaluation in recurrent patients and also in singleepisode patients when they have high recurrence risk. The extended evaluation has demonstrated to be costeffective in patients with highly recurrent lithiasis. There is not enough clinical evidence yet on what would be the most convenient study methodology for a proper metabolic evaluation, and proposed clinical guidelines are mainly based on expert committee opinions.With these studies, we can diagnose systemic and renal diseases of lithogenic nature, and they also enable the adoption of precise prophylactic measures that achieve recurrence control in a great number of patients.

[Age of onset of urolithiasis: relation to clinical and metabolic risk factors]. / Edad de comienzo de la enfermedad litiásica: relación con factores clínicos y de riesgo metabólico.

OBJECTIVES: To determine the age of onset of urolithiasis in patients with urinary calcium stones and to establish the relationship between age of onset and clinical profile and metabolic risk factors. METHODS: A total of 500 patients with the diagnosis of calcium urinary lithiasis (average age 47.4 years, range 20-75) were asked regarding the age of onset of the disease. Age of onset of urinary stone disease was compared with other factors such as gender, family history of lithiasis, clinical course, unique or recurrent episodes, and metabolic disturbances found in a comprehensive metabolic evaluation, using the chi-square test for categorical variables and analysis of variance (one way-ANOVA) with the Scheffe test for continuous variables. RESULTS: Mean age of onset of urinary stone disease was 38 years (range 4-73 years). This age of onset was lower in patients with low diuresis (31 years), family history of urolithiasis (32 years), hypercalciuria (36 years), recurrent disease (37 years), and hyperuricosuria (37 years). Significant differences were found in patients who had family history of urolithiasis (32 years) vs. those who did not have (40 years) (p < 0.01); patients with recurrent disease (37 years) vs. patients with a unique lithiasic episode (43 years) (p < 0.001); patients with hypercalciuria (36 years) vs. those who did not have (39 years) (p < 0.05); and also patients with low diuresis (31 years) vs. those with higher diuresis (39 years) (p < 0.001). CONCLUSIONS: The average age of onset of urolithiasis is significantly earlier in patients with low fluid intake habits, family history of urolithiasis, hypercalciuria and recurrent stone disease.

[Measuring the degree of patient satisfaction treated at an extracorporeal lithotripsy unit]. / Medición del grado de satisfacción del paciente tratado en una Unidad de Litotricia Extracorpórea.

OBJECTIVES: To determine by questionnaires the level of satisfaction of patients diagnosed of urinary lithiasis treated by extracorporeal shock wave lithotripsy (ESWL) in our Renal Stone Centre. METHODS: A total of 100 patients with urinary lithiasis who underwent ESWL, 54 males and 46 females with an average age of 50 years, answered a Lickert type questionnaire (score 1 to 5) consisting of 6 questions to evaluate the patient satisfaction regarding the treatment received. The relationship between answers to each question and patient's clinical characteristics were analyzed applying chi-square and linear regression to determine the level of significance of these relationships. RESULTS: General satisfaction level was high, with a mean score of 4.33 for the six questions. The most valued question was the one referred to assistance received in relation to the planned medical one. Questions referred to treatment suitability, expected timing, and absence of complexity were also highly valued. The least valued question was the one referred to pain level during treatment, which level was kept in a good approval degree with a mean score of 3.81 despite the fact that some patients said they suffered more pain than expected. CONCLUSIONS: ESWL resulted in a high level of satisfaction among patients treated for urinary lithiasis, revealed not only by its suitability, easy planning and performance, but also by its low level of complexity. Pain experienced by these patients during treatment was well-tolerated, so that general use of anesthesia was not required.