Por qué y cómo hemos de analizar los cálculos urinarios

context: there is heterogeneity of criteria on the utility of urinary stone analysis as well as on which is the most suitable methodology. this review presents the analysis of the lithiasis using the morphoconstitutional analysis technique based on the combination of the stereoscopic microscopy (sm) with infrared study (irs). summary of the evidence: there are many techniques to analyze the stone: chemical analysis, electron microscopy, x-ray diffraction, sm and irs. reviewing each one of these techniques and through the study of several clinical cases, this review shows the usefulness of stone analysis and the pros and cons of each one of the mentioned techniques. furthermore, it can be clearly seen how the morphoconstitutional analysis is the one that offers the most useful clinical information to the urologist. in addition, classification of the lithiasis based on this method and its clinical correlation with patients is presented. conclusions: using the morphoconstitutional study to analyze the stone offers more information than the other techniques and it makes it possible to establish a stone classification of important clinical and diagnostic utility.