Urinary Stone
Conditions
Keywords
2D:4D Digit Ratio, Urolithiasis, Kidney Stones, Urinary Stones, Prenatal Androgen Exposure
Brief summary
This prospective observational case-control study will investigate whether the 2D:4D digit ratio is associated with urinary stone disease. Adults undergoing non-contrast computed tomography at Malatya Training and Research Hospital will be classified as cases if kidney and/or ureteral stones are detected and as controls if no urinary stones are detected and there is no previous history of stone disease or stone surgery. The lengths of the second and fourth fingers of both hands will be measured using a digital caliper by two independent observers who are blinded to the participant group. The study will also examine whether the 2D:4D ratio is associated with recurrent stone disease, stone burden, and bilateral or multiple stones.
Interventions
None listed
Sponsors
Emrah Kızılay
Study design
Observational model
CASE_ONLY
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 18 years or older * Provision of written informed consent * Undergoing non-contrast computed tomography at Malatya Training and Research Hospital during the study period * For cases: presence of at least one kidney and/or ureteral stone on non-contrast computed tomography * For controls: absence of stones in the kidneys, ureters, and bladder on non-contrast computed tomography * For controls: no previous physician-diagnosed urinary stone disease or history of stone-related surgery * Feasibility of bilateral second- and fourth-digit length measurements
Exclusion criteria
* Congenital deformity of the hands or fingers * History of hand or finger trauma, fracture, surgery, or amputation that may affect digit length measurement * Severe hand deformity, contracture, or advanced joint disease preventing reliable measurement * Incomplete, inadequate, or technically unreliable 2D:4D measurements * Missing essential clinical, demographic, or imaging data * Pregnancy * Presence of bladder stones * Urinary diversion, major urinary tract reconstruction, or a significant structural urinary tract anomaly
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean Bilateral 2D:4D Digit Ratio by Urinary Stone Disease Status | At enrollment, during the single study assessment | The lengths of the second and fourth digits of both hands will be measured using a digital caliper by two independent observers blinded to group status. Right and left 2D:4D ratios will be calculated by dividing the length of the second digit by the length of the fourth digit. The mean bilateral 2D:4D ratio will be calculated as the average of the right and left ratios and compared between participants with computed tomography-confirmed kidney and/or ureteral stones and stone-free controls. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Mean Bilateral 2D:4D Digit Ratio by Recurrent Stone Disease Status | At enrollment, during the single study assessment | Among participants with computed tomography-confirmed kidney and/or ureteral stones, recurrent stone disease will be defined as at least one previous physician-diagnosed urinary stone episode, spontaneous stone passage, or stone-related surgical intervention before the current stone episode. The mean bilateral 2D:4D ratio will be compared between participants with recurrent stone disease and those experiencing their first documented stone episode. |
| Association Between Mean Bilateral 2D:4D Digit Ratio and Total Stone Burden | At enrollment, during the single study assessment | Among participants with computed tomography-confirmed kidney and/or ureteral stones, total stone burden will be calculated as the sum of the maximum diameters of all detected stones in millimeters on non-contrast computed tomography. The association between mean bilateral 2D:4D ratio and total stone burden will be evaluated. |
| Mean Bilateral 2D:4D Digit Ratio by Bilateral and/or Multiple Stone Presentation | At enrollment, during the single study assessment | Among participants with computed tomography-confirmed kidney and/or ureteral stones, bilateral stone disease will be defined as the presence of stones on both sides of the urinary tract, and multiple stone disease will be defined as the presence of two or more distinct stones. The mean bilateral 2D:4D ratio will be compared between participants with bilateral and/or multiple stones and those with a solitary unilateral stone. |
Countries
Turkey (Türkiye)
Contacts
CONTACTEmrah KIZILAY, MD
PRINCIPAL_INVESTIGATOREmrah KIZILAY
Malatya Training and Research Hospital
Outcome results
None listed