Investigation at the micrometer scale of pancreatic calcifications in chronic pancreatitis by μFTIR spectroscopy and field emission scanning electron microscopy

Fine-needle aspiration of a pancreas with squamoid cyst of pancreatic duct and pancreatic duct stones: A case report of a rare pancreatic lesion and an unusual concurrent finding of stone-related crystals

Squamoid cyst of pancreatic duct is a rare benign pancreatic lesion that is rarely encountered in fine-needle aspiration (FNA) and surgical resection specimens. Pancreatic stones can be seen in chronic pancreatitis, but stone-related crystals have previously not been described in pancreatic cytology. Presented here is a case report of a squamoid cyst of pancreatic duct with concurrent pancreatic duct stones. We describe the cytomorphology of this benign cyst, as well as the remarkable finding of polymorphous crystals on cyst fluid aspirate. We also describe the histology of the surgically resected cystic lesion. With the increase in detection of incidental pancreatic cysts on imaging, this case highlights the importance of awareness and recognition of benign non-neoplastic epithelial cysts on FNA sampling to avoid overtreatment. The presence of crystals on pancreatic FNA is an unusual finding, likely representing calcium carbonate crystals related to the formation of pancreatic duct stones.

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. This paper confirms the complex morphology and nature that urinary crystals may at times have and the utility of advanced infrared spectroscopy techniques for their identification.

Pathological Mineralization: The Potential of Mineralomics

Pathological mineralization has been reported countless times in the literature and is a well-known phenomenon in the medical field for its connections to a wide range of diseases, including cancer, cardiovascular, and neurodegenerative diseases. The minerals involved in calcification, however, have not been directly studied as extensively as the organic components of each of the pathologies. These have been studied in isolation and, for most of them, physicochemical properties are hitherto not fully known. In a parallel development, materials science methods such as electron microscopy, spectroscopy, thermal analysis, and others have been used in biology mainly for the study of hard tissues and biomaterials and have only recently been incorporated in the study of other biological systems. This review connects a range of soft tissue diseases, including breast cancer, age-related macular degeneration, aortic valve stenosis, kidney stone diseases, and Fahr’s syndrome, all of which have been associated with mineralization processes. Furthermore, it describes how physicochemical material characterization methods have been used to provide new information on such pathologies. Here, we focus on diseases that are associated with calcium-composed minerals to discuss how understanding the properties of these minerals can provide new insights on their origins, considering that different conditions and biological features are required for each type of mineral to be formed. We show that mineralomics, or the study of the properties and roles of minerals, can provide information which will help to improve prevention methods against pathological mineral build-up, which in the cases of most of the diseases mentioned in this review, will ultimately lead to new prevention or treatment methods for the diseases. Importantly, this review aims to highlight that chemical composition alone cannot fully support conclusions drawn on the nature of these minerals.

[The role of physicochemistry in urology and nephrology, selected results obtained during the last ten years]

INTRODUCTION

The presence of pathological calcifications, which can be either concretions or ectopic call for physicochemical characterisation techniques in order to define a significant diagnosis. The aim of this review is to present a set of characterisation techniques able to describe at the micrometer scale their structural and chemical characteristics and show their place at the hospital.

METHOD

Results already published in the last ten years based on characterisation techniques present in laboratories or specific to large-scale instruments are presented. Their usefulness for the clinician is discussed.

RESULTS

The presence and role of heavy metals in urinary stones through data collected through μX-ray fluorescence is debated. If these data suggest a simple substitution process of calcium, recent data suggest that weddellite is associated to a Zn-rich environment, partly favoured by an inflammation process. Investigation on the chemistry and the structure of unusual deposits in kidney biopsies show a great chemical diversity of ectopic calcifications. Such diversity shows that staining procedures to characterize such deposits are obsolete. Finally, several diseases which can be assessed through techniques specific to large-scale instruments and defined by the clinician are presented.

CONCLUSION

The chemical and structural complexity of pathological calcifications call for a characterization through physicochemical techniques. Only such approach allows the clinician to define a significant diagnosis and to care the patient.