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GeoBioMed — a new transdisciplinary approach that integrates the fields of geology, biology and medicine — reveals that kidney stones composed of calcium-rich minerals precipitate from a continuum of repeated events of crystallization, dissolution and recrystallization that result from the same fundamental natural processes that have governed billions of years of biomineralization on Earth. This contextual change in our understanding of renal stone formation opens fundamentally new avenues of human kidney stone investigation that include analyses of crystalline structure and stratigraphy, diagenetic phase transitions, and paragenetic sequences across broad length scales from hundreds of nanometres to centimetres (five Powers of 10). This paradigm shift has also enabled the development of a new kidney stone classification scheme according to thermodynamic energetics and crystalline architecture. Evidence suggests that ≥50% of the total volume of individual stones have undergone repeated in vivo dissolution and recrystallization. Amorphous calcium phosphate and hydroxyapatite spherules coalesce to form planar concentric zoning and sector zones that indicate disequilibrium precipitation. In addition, calcium oxalate dihydrate and calcium oxalate monohydrate crystal aggregates exhibit high-frequency organic-matter-rich and mineral-rich nanolayering that is orders of magnitude higher than layering observed in analogous coral reef, Roman aqueduct, cave, deep subsurface and hot-spring deposits. This higher frequency nanolayering represents the unique microenvironment of the kidney in which potent crystallization promoters and inhibitors are working in opposition. These GeoBioMed insights identify previously unexplored strategies for development and testing of new clinical therapies for the prevention and treatment of kidney stones. The formation of kidney stones is governed by the same principles as other stone systems. These ‘diagenetic phase transitions’ that create human kidney stones reflect the environment within the kidney during stone formation and could, therefore, improve understanding of urolithiasis and enable future treatment development. In this wide-ranging and unique Review, the authors explain how kidney stone formation parallels that of other stone systems such as stony corals, travertine in Roman aqueducts, stalactites and agates, and describe how the new field of GeoBioMed could be harnessed to improve patient care.

An estimated 4–5 million CT scans are performed in the USA every year to investigate nephrourological diseases such as urinary stones and renal masses. Despite the clinical benefits of CT imaging, concerns remain regarding the potential risks associated with exposure to ionizing radiation. To assess the potential risk of harmful biological effects from exposure to ionizing radiation, understanding the mechanisms by which radiation damage and repair occur is essential. Although radiation level and cancer risk follow a linear association at high doses, no strong relationship is apparent below 100 mSv, the doses used in diagnostic imaging. Furthermore, the small theoretical increase in risk of cancer incidence must be considered in the context of the clinical benefit derived from a medically indicated CT and the likelihood of cancer occurrence in the general population. Elimination of unnecessary imaging is the most important method to reduce imaging-related radiation; however, technical aspects of medically justified imaging should also be optimized, such that the required diagnostic information is retained while minimizing the dose of radiation. Despite intensive study, evidence to prove an increased cancer risk associated with radiation doses below ~100 mSv is lacking; however, concerns about ionizing radiation in medical imaging remain and can affect patient care. Overall, the principles of justification and optimization must remain the basis of clinical decision-making regarding the use of ionizing radiation in medicine. Investigation of nephrourological diseases is a common indication for CT examination. However, concerns remain regarding the potential risks associated with exposure to ionizing radiation despite a lack of convincing evidence for any such effect at the low doses used for CT scanning. In this Review, experts in the field explain the data in this area and consider how elimination of unnecessary imaging and optimization of medically justified imaging must remain the basis of clinical decision-making.

Technology for the treatment of stone disease has rapidly advanced, but a common nomenclature to communicate research and high-quality studies to assess treatment outcomes are lacking. Thus, guidelines are based on low-grade evidence and cannot make definitive recommendations in many scenarios. To improve clinical practice and patient outcomes, the endourology community must unite to address these inadequacies.

GeoBioMed, a new multidisciplinary approach, combines geology, biology, urology and microscopy to discover unorthodox treatments. Results indicate that calcium oxalate kidney stones undergo previously unforeseen cycles of repeated crystallization, dissolution, fracturing and faulting. GeoBioMed challenges clinical paradigms for in vivo stone formation and treatment as well as biomineralization in natural and engineered environments.

A study investigating the mortality attributed to urolithiasis over a 15-year period has noted an increasing rate of death with a simultaneous rise in stone prevalence. However, the exact mechanisms by which nephrolithiasis causes death remains unclear.