BERKELEY, CA (UroToday.com) - In a recent journal article, Dr. Marc Smaldone et al., described a meta-analysis performed with a comprehensive literature review using Medline and PubMed to evaluate indications, techniques, complications and efficacy of endourologic stone management in children.
With regard to shock wave lithotripsy, they found that there is currently no consensus for the maximum size of residual stone fragments that are considered clinically significant. There is also no clear definition as to what constitutes a stone-free status. There seems to be a consensus that approximately 60% of people can be treated with one shock wave therapy. This has been also shown in other studies to be as high as 84%.
Regarding percutaneous nephrostolithotomy, stone-free rates range from 68% to 100% after one PCNL treatment with or without combination shock wave lithotripsy called sandwich therapy. A recent large retrospective series of percutaneous nephrostolithotomy showed a 90% success rate with one procedure. It also appears that ureteroscopy, both rigid and flexible, have generally over a 90% success rate in children with almost half the children requiring a repeat procedure to either remove a stent or place a stent primarily - for passive dilation. There have been reports of both laparoscopic and robotic assisted pyelolithotomy. The laparoscopic approach described in 2004 showed that there was a 100% success rate on 8 children. Subsequent robotic pyelolithotomy ensued with 5 cases, 4 of which were completed robotically and 1 requiring an open conversion. Although in its infancy, this seems to be another minimally invasive approach that merits further investigation.
It appears that the evolving techniques of minimally invasive surgery with smaller and smaller instrumentations have radically changed the management of pediatric stone disease. Nonetheless the morbidity of having this disease is quite high and we should concentrate more on preventative measures than operative intervention. It has been my experience that approximately 1/3 of the patients that we care for with stones require some surgical procedure and over half of these patients have repeat stone burdens that require surgery later on. We need to make their diagnoses of why they form stones through 24 hour urine analyses and other parameters such as parathyroid hormone levels as well as vitamin D levels. I also feel it might be prudent to start to perform bone surveys for bone density studies on patients who are repeated stone formers. It might even be prudent to do gene array studies to see if there is any cluster of genes that might be either affected or implied in the stone forming population.
Smaldone MC, Corcoran AT, Docimo SG, Ost MC
J Urol. 2009 Jan;181(1):17-28
10.1016/j.juro.2008.09.001
PubMed Abstract
PMID: 19012920