This retrospective observational study investigates the metabolic abnormalities associated with different types of kidney stones by analyzing their composition. The study includes adult patients diagnosed with urolithiasis, whose stone samples were analyzed using Fourier Transform Infrared (FTIR) spectroscopy. Clinical, biochemical, and 24-hour urine metabolic parameters were compared between first-time and recurrent stone formers, and among subtypes of calcium oxalate stones (monohydrate vs. dihydrate). The goal is to identify metabolic risk factors that contribute to stone formation and recurrence, and to provide insights for individualized prevention strategies.

This retrospective study aims to evaluate the metabolic characteristics of patients with urolithiasis based on kidney stone composition. Data were collected from patients treated for kidney stones between January 2010 and December 2024 at a tertiary urology center. Stone analysis was performed using FTIR spectroscopy, classifying stones into subtypes including calcium oxalate monohydrate (COM), calcium oxalate dihydrate (COD), uric acid, and mixed types.

Serum levels of calcium, phosphorus, uric acid, creatinine, and parathyroid hormone (PTH), along with 24-hour urine values (calcium, oxalate, citrate, uric acid, volume, and pH), were recorded. The study primarily compares metabolic differences between:

First-time vs. recurrent stone formers

COM vs. COD stone subtypes

Findings from this study are expected to improve understanding of metabolic risk factors and contribute to the development of tailored metabolic evaluations and dietary or pharmacological preventive strategies for recurrent stone formers.

Inclusion Criteria:

• Age ≥ 18 years
• Patients diagnosed with kidney stones between January 2010 and December 2024
• Stone composition analyzed via Fourier-transform infrared (FTIR) spectroscopy
• Available metabolic panel including serum and 24-hour urine values

Exclusion Criteria:

• Patients with secondary hyperparathyroidism, renal tubular acidosis, or other systemic metabolic diseases affecting stone formation
• Patients with incomplete medical records
• Patients with non-calcium-based stones (e.g., uric acid, struvite, cystine)

This study included 506 patients who presented with nephrolithiasis and underwent metabolic evaluation of stone composition. Data were collected retrospectively from medical records at Hisar Intercontinental Hospital between 2010 and 2024.

De-identified individual participant data (IPD) to be shared include stone composition types (e.g., calcium oxalate monohydrate vs dihydrate), serum metabolic parameters (e.g., calcium, phosphorus, PTH), and 24-hour urine findings (e.g., oxalate, citrate, pH, sodium, uric acid).

Data will be made available 6 months after publication of the main study results and will remain accessible for a period of 36 months upon request.

Qualified researchers affiliated with academic or healthcare institutions may request access to the de-identified IPD for secondary analysis or meta-analysis. Requests should be submitted to the corresponding author with a detailed research proposal. Data access will be granted following review and under a data-sharing agreement.