IJU this issue

Abstract

The rationale of partial nephrectomy is preservation of renal function. Kim et al. (Seoul, Korea) analyzed the temporal 2-year profile of ipsilateral and contralateral kidney function in 62 cases after robot-assisted partial nephrectomy. Renal parenchymal volume was quantitated using 3-D semi-automatic segmentation technology. Estimated glomerular filtration rate was reduced in the early days, but recovered to 2.4% loss at 2 years post-partial nephrectomy. The change in total estimated glomerular filtration rate was most efficiently predicted by preoperative estimated glomerular filtration rate. As for renal volume, the volume of the ipsilateral kidney was stable, whereas the contralateral renal volume increased with time from 2.3% at 6 months to 12.9% at 2 years. The tumor size and the kidney volume lost during surgery were the significant predictive factors for volume enlargement of the contralateral kidney. The physiology of so-called compensatory hypertrophy remains understudied. Its elucidation possibly contributes to recovery of ipsilateral kidney volume or regenerative medicine of renal parenchyma. Another topic highlighted in this issue is the clinical application of the botulinum toxin to control overactive bladder and associated urinary incontinence. Everaert et al. (Ghent, Belgium) carried out a pooled analysis of outcomes in anticholinergic-resistant wet patients. The treatment clearly improved practical aspects of the patients’ daily lives, including pad use, need to change underwear, sleep, relationship with partner and work activities. Significantly greater proportions of patients treated with onabotulinumtoxinA 100 U (n = 557) achieved positive Treatment Benefit Scale response (condition “greatly improved” or “improved”) versus placebo (n = 548; 61.8% vs 28.0%, P < 0.001). The benefit was also proven by Incontinence Quality of Life total, Incontinence Quality of Life subscale scores and all domains of the King's Health Questionnaire. The improvement was observed regardless of clean intermittent catheterization/urinary tract infection status. Despite such a remarkable efficacy of botulinum toxin, repeated injection is sometimes required to attain or maintain the clinical benefit. Peyronnet et al. (Toulouse, France) retrospectively compared the efficacy of a second injection of botulinum toxin depending on the kind of toxin used for the second injection. Patients with neurogenic detrusor overactivity failed at the first injection received of either the same toxin of the first injection or a different botulinum toxin. The toxin injected was abobotulinumtoxinA or onabotulinumtoxinA. The outcome was measured by resolution of urgency, urinary incontinence and detrusor overactivity. Of a total of 58 patients, 29 patients each received the same toxin or the alternative. Interestingly, the success rate was higher in toxin-switched cases (51.7% vs 24.1%; P = 0.03), regardless of the kind of toxin, with 52.9% in a switch from abobotulinumtoxinA to onabotulinumtoxinA and 50% in a switch from onabotulinumtoxinA to abobotulinumtoxinA. This observation cannot be explained by accumulation of toxin or neutralizing antibody to toxin. Basic science is warranted to understand the pharmacological properties or immunogenicity of the botulinum toxin, a neurotoxic protein with a complicated structure. None declared.