A correlation study between macro- and micro-analysis of pediatric urinary calculi

Area of Science:

• Urology
• Analytical Chemistry
• Pediatric Nephrology

Background:

• Pediatric urinary stones (calculi) are complex formations whose comprehensive compositional analysis is crucial for understanding their etiology.
• Combined analytical techniques offer a more detailed insight into the macro- and micro-composition of these stones.

Purpose of the Study:

• To investigate the relationship between the macro- and micro-compositions of pediatric urinary stones.
• To utilize Fourier transform infrared spectroscopy (FT-IR) and inductively coupled plasma-optical emission spectrometry (ICP-OES) for stone analysis.

Main Methods:

• Analysis of 74 pediatric urinary calculi using FT-IR for mineralogical composition and ICP-OES for elemental content (heavy metals and trace elements).
• Each stone was divided, with one half analyzed by FT-IR and the other by ICP-OES.
• Statistical evaluation of the association between mineralogical components and elemental concentrations.

Main Results:

• Predominant mineralogical components included calcium oxalate monohydrate (78.3%) and dihydrate (63.5%), with significant presence of ammonium urate, uric acid, dahllite, brushite, and struvite.
• Seven elements showed significantly different high concentrations: magnesium, sulfur, strontium, lead, chromium, calcium, and phosphorus.
• Stones high in calcium had elevated levels of magnesium, lead, strontium, and zinc; phosphate stones exhibited higher concentrations of magnesium, strontium, zinc, and chromium.

Conclusions:

• Pediatric urinary stones exhibit variable biochemical structures.
• Significant concentrations of various heavy metals and trace elements were detected.
• Phosphate-containing stones were associated with the highest levels of heavy and trace elements.