Calcium and calcium magnesium carbonate specimens submitted as urinary tract stones

Characterization of dolomite and calcite microcalcifications in human breast tissue

Pathological crystallization within soft tissues often yields biominerals with properties differing from those of their geological or synthetic counterparts. Microcalcifications (MCs) are abundant in breast tumors, particularly in non-invasive lesions, such as ductal carcinoma in situ (DCIS). Given the challenge of predicting DCIS progression into invasive cancer, it has been suggested that MCs can be leveraged to inform DCIS prognosis. The predominant type of breast MCs are those containing calcium phosphates (CaP), whose crystal properties are commonly held to correlate with malignancy. Less common are non-CaP minerals, which have received less attention, as they are associated mainly with benign lesions. Here, we conducted a retrospective study of tissue samples collected from patients who were originally diagnosed with DCIS and whose current medical status is known. We examined the elemental composition, morphology, and crystal phases of 398 MCs, aiming to investigate potential correlations between MC crystal properties and the progression of DCIS. Our findings revealed primarily non-CaP MCs, an observation that was likely made possible only by the tissue processing methodology employed, which did not involve harsh conditions. We found that non-CaP MCs were abundant in DCIS lesions, that they exhibited diverse morphologies and sizes, and that they were composed of calcite and dolomite. Dolomite formation in cancer has not been reported previously and may be linked to pH fluctuations in the tumor microenvironment. The small size of DCIS lesions often requires pathologists to use the entire sample, thus reducing the number of samples available for further research. Nonetheless, despite our limited sample size, the observed trend indicated an association of dolomite MCs with DCIS lesions that progressed into invasive cancer over time.

Long-term ketone body therapy of severe multiple acyl-CoA dehydrogenase deficiency: A case report

OBJECTIVES

Multiple acyl-CoA dehydrogenase deficiency (MADD) is the most severe disorder of mitochondrial fatty acid β-oxidation. Treatment of this disorder is difficult because the functional loss of the electron transfer flavoprotein makes energy supply from fatty acids impossible. Acetyl-CoA, provided by exogenous ketone bodies such as NaßHB, is the only treatment option in severe cases. Short-term therapy attempts have shown positive results. To our knowledge, no reports exist concerning long-term application of ketone body salts in patients with severe MADD.

METHODS

This case report is a detailed retrospective metabolic analysis of a boy with severe MADD. Treatment with sodium β-hydroxybutyrate (NaβHB) started 8 d after birth using gradually increasing doses. In the initial phase, metabolic and acid-base parameters were checked multiple times a day. After 8 y of standardized therapy with 16 g NaβHB, substitution with calcium β-hydroxybutyrate (CaβHB) was attempted. In addition to the β-hydroxybutyrate (βHB) supplementation, continuous adjustments were made to the child's nutrition to provide necessary nutrients.

RESULTS

Treatment with βHB salts leads to adverse effects like gastrointestinal discomfort and alkalosis. Measured concentrations of βHB were predominantly at 0.1 mmol/L or below detectable concentration. Nutritional therapy based on amino acid and acylcarnitine profiles is a necessary part of the therapy in MADD.

CONCLUSIONS

Therapy with NaβHB is lifesaving in cases of severe MADD but can have significant adverse effects. Supplementation with CaβHB led to gastrointestinal discomfort and had no additional positive clinical effect. The determined tolerable dose of βHB salt for long-term therapy was not high enough for a notable increase of βHB concentrations in blood.

Recurrent Pure Calcite Urolithiasis Confirmed by Endoscopic Removal and Infrared Spectroscopy in a Malnourished Anorectic Female

Often when calcite is found as a component of urinary calculi, they are considered false calculi or artifacts. We present a case of true calcite urolithiasis. The stone material was removed percutaneously from a severely malnourished anorectic woman and analyzed by infrared spectroscopy (IRS). In addition, calcite urolithiasis was confirmed in several recurrent stone events by IRS. Laxative abuse with magnesium oxide was believed to be the underlying cause of stone formation, and ammonium chloride given as one weekly dose turned out to be effective for stone prevention.

Calcium carbonate crystals promote calcium oxalate crystallization by heterogeneous or epitaxial nucleation: possible involvement in the control of urinary lithogenesis

A large proportion of urinary stones have calcium oxalate (CaOx) as the major mineral phase. In these stones, CaOx is generally associated with minor amounts of other calcium salts. Several reports showing the presence of calcium carbonate (CaCO3) and calcium phosphate in renal stones suggested that crystals of those salts might be present in the early steps of stone formation. Such crystals might therefore promote CaOx crystallization from supersaturated urine by providing an appropriate substrate for heterogeneous nucleation. That possibility was investigated by seeding a metastable solution of 45Ca oxalate with vaterite or calcite crystallites. Accretion of CaOx was monitored by 45Ca incorporation. We showed that (1) seeds of vaterite (the hexagonal polymorph of CaCO3) and calcite (the rhomboedric form) could initiate calcium oxalate crystal growth; (2) in the presence of lithostathine, an inhibitor of CaCO3 crystal growth, such accretion was not observed. In addition, scanning electron microscopy demonstrated that growth occurred by epitaxy onto calcite seeds whereas no special orientation was observed onto vaterite. It was concluded that calcium carbonate crystals promote crystallization of calcium oxalate and that inhibitors controlling calcium carbonate crystal formation in Henle's loop might play an important role in the prevention of calcium oxalate stone formation.

Carbonate in struvite stone detected in Raman spectra compared with infrared spectra and X-ray diffraction

BACKGROUND

In regard to identify the compositions of urinary stones, the infrared spectra is a contemporary routine method. However, it is difficult to detect the absorption of carbonate in struvite stone by infrared spectra, because NH4 absorption of magnesium ammonium phosphate overlaps CO3 absorption of carbonate at 1420-1435 cm-1. With the purpose of demonstrating the existence of carbonate in struvite stones, the analysis of these stones by means of Raman spectra has been tried.

METHODS

Forty urinary stones, the chemical compositions of which were previously determined by infrared spectroscopy, were submitted to Raman spectrum analysis, and subsequently to analysis by x-ray diffraction.

RESULTS

Thirty of 40 urinary stones were found to be composed of struvite and of mixed struvite-calcium oxalate by infrared analysis. Twelve of these stones were shown to have Raman spectra of magnesium ammonium phosphate, and the other stones to have spectra of apatite. By x-ray diffraction magnesium ammonium phosphate crystals were detected in 25 of these struvite stones and hydroxyl-apatite in another 3, and 2 cases were undeterminable. For other components, such as calcium oxalate, uric acid and cystine, the analytical results of infrared spectra coincided with those of Raman spectra and x-ray diffraction. Carbonate was detected in only a part of one struvite stone by Raman spectra.

CONCLUSIONS

Above-mentioned results may indicate that carbonate is only a minor component of urinary stones. Therefore, most of 1420-1435 cm-1 bands on the infrared spectra of struvite stones do not indicate CO3 absorption of carbonate, but NH(4) absorption of magnesium ammonium phosphate.