Uta Michibata et al., 2024: The impact of crystal phase transition on the hardness and structure of kidney stones
Uta Michibata 1 , Mihoko Maruyama 2 3 , Yutaro Tanaka 1 4 , Masashi Yoshimura 5 , Hiroshi Y Yoshikawa 1 , Kazufumi Takano 6 , Yoshihiro Furukawa 7 , Koichi Momma 8 , Rie Tajiri 9 , Kazumi Taguchi 4 , Shuzo Hamamoto 4 , Atsushi Okada 4 , Kenjiro Kohri 4 , Takahiro Yasui 4 , Shigeyoshi Usami 1 , Masayuki Imanishi 1 , Yusuke Mori 1
1Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, 565-0871, Japan.
2Graduate School of Engineering, Osaka University, 2-1, Yamadaoka, Suita, 565-0871, Japan.
3Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5, Hangi-cho, Shimogamo, Sakyo-ku, Kyoto, 606-8522, Japan.
4Department of Nephro-urology, Graduate School of Medical Sciences, Nagoya City University, 1-Kawasumi, Mizuho- cho, Mizuho-Ku, Nagoya, 467-8601, Japan.
5Institute of Laser Engineering, Osaka University, 2-6, Yamadaoka, Suita City, 565-0871, Osaka, Japan.
6Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, 1-5, Hangi-cho, Shimogamo, Sakyo-ku, Kyoto, 606-8522, Japan.
7Department of Earth Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai, 980-8578, Japan.
8National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba, 305-0005, Japan.
9Tajiri Thin Section Laboratory, 3-1-11 Sannose, Higashiosaka, 577-0849, Osaka, Japan.
Abstract
Calcium oxalate kidney stones, the most prevalent type of kidney stones, undergo a multi-step process of crystal nucleation, growth, aggregation, and secondary transition. The secondary transition has been rather overlooked, and thus, the effects on the disease and the underlying mechanism remain unclear. Here, we show, by periodic micro-CT images of human kidney stones in an ex vivo incubation experiment, that the growth of porous aggregates of calcium oxalate dihydrate (COD) crystals triggers the hardening of the kidney stones that causes difficulty in lithotripsy of kidney stone disease in the secondary transition. This hardening was caused by the internal nucleation and growth of precise calcium oxalate monohydrate (COM) crystals from isolated urine in which the calcium oxalate concentrations decreased by the growth of COD in closed grain boundaries of COD aggregate kidney stones. Reducing the calcium oxalate concentrations in urine is regarded as a typical approach for avoiding the recurrence. However, our results revealed that the decrease of the concentrations in closed microenvironments conversely promotes the transition of the COD aggregates into hard COM aggregates. We anticipate that the suppression of the secondary transition has the potential to manage the deterioration of kidney stone disease.
Urolithiasis. 2024 Apr 2;52(1):57. doi: 10.1007/s00240-024-01556-5.
PMID: 38563829 PMCID: PMC10987347 DOI: 10.1007/s00240-024-01556-5
Comments 1
A very detailed and meticulous study on the formation of Calcium-oxalate-monohydrate formation in urinary stones.
“One of the methods of stone treatment and prevention is drinking plenty of water, but the decrease in urinary calcium oxalate supersaturation caused by this drinking may accelerate the progression of phase transitions, thereby making the stones more malignant. Thus, the follow-up of lithiasis leads to stone hardening, i.e., worsening of the stones in the body. The findings of this study strongly support the need for early treatment in clinical practice.”
This reminds me of long-ago-moments when I gave up believing that metabolists could solve the stone problem. At that time, experts were publicly arguing about the most prominent recommendation of stone prevention: the effect a high fluid intake could have on stone disease. Those who believed more in the inhibitors of crystallization argued against too much fluid because of inhibitor concentration lowering; those who believed that the concentration of stone-forming substances was decisive were in favour of it.
Peter Alken