Ray Eleanor R, Rumsby Gill, Smith R Daron
Department of Urology, University College Hospital London, London, UK.
Department of Biochemistry, University College Hospital London, London, UK.
BJU Int. 2016 Oct;118(4):618-24. doi: 10.1111/bju.13448. Epub 2016 Mar 21.
To determine if the biochemical composition of a renal calculus can be measured from 'dust' obtained during laser fragmentation.
This pilot study was set in a tertiary referral hospital between 2011 and 2013. Stone dust was aspirated through the ureteroscope during lasering and a stone fragment also retrieved. Both samples were analysed by Fourier transform infrared spectroscopy. Pairs of stone (standard) and dust were compared. They were deemed to match if both were of the same pure biochemical composition or if the predominant constituent was the same in mixed compositions, as this would not alter subsequent management.
Paired specimens were obtained from 97 ureteroscopies. The dust specimen was sufficient for analysis in 66/97 (68%) cases. Of these, the composition matched that of the stone in 49/66 (74%) cases. In 12/66 (18%) the biochemistry differed only in the relative proportions of each constituent, whilst 5/66 (8%) showed a complete mismatch. The overall sensitivity was 51% and specificity 97%. A limitation of the study is the small number of some stone types analysed (<5 each cystine, atazanavir, mixed uric acid/calcium oxalate).
We have demonstrated in this pilot study successful proof of principle. Further work is required initially to improve the number of sufficient dust specimens. This technique may offer an option when a stone cannot be retrieved ureteroscopically.
确定能否通过激光碎石过程中获取的“粉末”来测量肾结石的生化成分。
这项前瞻性研究于2011年至2013年在一家三级转诊医院开展。激光碎石时通过输尿管镜吸取结石粉末，并获取一块结石碎片。对这两个样本均采用傅里叶变换红外光谱法进行分析。将结石（标准样本）与粉末样本进行配对比较。如果两者具有相同的纯生化成分，或者在混合成分中主要成分相同，则认为它们匹配，因为这不会改变后续的治疗方案。
从97例输尿管镜检查中获取了配对样本。在66/97（68%）的病例中，粉末样本足以进行分析。其中，49/66（74%）的病例中粉末成分与结石成分匹配。在12/66（18%）的病例中，生化成分仅在各成分的相对比例上有所不同，而5/66（8%）的病例则显示完全不匹配。总体敏感性为51%，特异性为97%。该研究的一个局限性是某些结石类型的分析数量较少（胱氨酸结石、阿扎那韦结石、尿酸/草酸钙混合结石每种均少于5例）。
在这项前瞻性研究中我们已成功证明了原理。最初需要进一步开展工作以增加足够的粉末样本数量。当无法通过输尿管镜取出结石时，这项技术可能提供一种选择。
