Advances in the identification of calcium carbonate urinary crystals.

The examination of the urinary sediment of a 64-year-old woman showed the presence of three different types of crystals, all with unusual morphology, which could not be identified with bright field microscopy, polarized light, and the knowledge of urine pH (7.5). The use of microscopic infrared spectroscopy, Raman spectroscopy and energy dispersive X-ray spectroscopy led to the identification of the three types of crystals as calcite, vaterite and aragonite, which are all variants of calcium carbonate crystals.

A virtuous diagnostic and therapeutic roadmap triggered by a motivated and skilful urinary sediment examination.

In this paper we describe how an accurate urinary sediment examination, which revealed the presence of a severe 2,8-dihydroxyadenine crystalluria, opened the way to an articulate and successful diagnostic and therapeutic roadmap for a rare and potentially severe renal disease.

[PHYSICAL, CHEMICAL AND MORPHOLOGICAL URINE EXAMINATION: RECOMMENDATIONS FOR THE POST ANALYTICAL PHASE FROM THE INTERDISCIPLINARY URINALYSIS GROUP (GIAU)].

With these recommendations the Interdisciplinary Urinalysis Group (GIAU) aims to stimulate the following aspects : improvement and standardization of the post analytical approach to physical, chemical and morphological urine examination (ECMU); emphasize the value added to ECMU by selection of clinically significant parameters, indication of analytical methods, of units of measurement, of reference values; improvement of interpretation of dip stick urinalysis with particular regard to the reconsideration of the diagnostic significance of the evaluated parameters together with an increasing awareness of the limits of sensitivity and specificity of this analytical method. Accompanied by the skills to propose and carry out in-depth investigations with analytical methods that are more sensitive and specific;increase the awareness of the importance of professional skills in the field of urinary morphology and their relationships with the clinicians. through the introduction, in the report, of descriptive and interpretative comments depending on the type of request, the complexity of the laboratory, the competence of the pathologist;implement a policy of evaluation of the analytical quality by using, in addition to traditional internal and external controls, a program for the evaluation of morphological competence.

Very unusual "needle- and pencil-like" uric acid crystals in the urine unmasked by infrared spectroscopy investigation.

In this paper we describe a case with very unusual "needle- and pencil-like" crystals, partly similar to those reported by other investigators, who considered them as due to uric acid. Quite importantly, infrared spectroscopy investigation which, to our knowledge, we have been the first to perform on this type of crystals, confirmed their nature as uric acid structures. This case demonstrates that the planet of urinary crystals still has several unknown facets and still deserves exploration.

"Daisy-like" crystals: A rare and unknown type of urinary crystal.

Background: Crystals are well known structures of urinary sediment, most of which are identified by the combined knowledge of crystal morphology, birefringence features at polarized light, and urine pH. In this paper, we report on a cohort of subjects whose urine contained a very rare type of crystal, which we first described in 2004 and which, based on its peculiar morphology, we define as "daisy-like crystal" (DLcr).

Methods: Reports on DLcr were spontaneously sent to our laboratory over a 10.