Commentary to ‘Early clean intermittent catheterization may not prevent dimercaptosuccinic acid renal scan abnormalities in children with spinal dysraphism’

Abstract

The authors aimed to address a clinically relevant issue: do we prevent new renal scarring by early administration of clean intermittent catheterization (CIC) in patients with spina bifida? In 2006, Peter Dik and co-workers presented their results of the concept of prophylactic initiation of CIC combined with antimuscarinic therapy in myelodysplastic newborns. Out of 144 children, five patients had pre-existing renal abnormalities, 69 had an overactive sphincter, 27 had reflux, and six had renal scarring. Five of the six patients with renal scarring were put on CIC and antimuscarinic therapy several months after birth. This study provided prima facie evidence that early initiation of CIC and antimuscarinics has the potential to prevent new renal scars [1]. In the presented study, postnatal CIC combined with antimuscarinics was performed in 17 out of 100 patients. A dimercaptosuccinic acid (DMSA) scan was only carried out if a pathology was found or suspected. These 17 patients were compared with a markedly larger group of 83 patients in whom CIC was initiated at a median age of 5 years. Moreover, only the latest DMSA scan was reviewed. Although the authors are to be congratulated on a wellthought-out and well-written manuscript, the study has several limitations which may not support the conclusions drawn by the authors. First, this is a small retrospective series and, more importantly, there is not uniformity in the groups. Second, there is a wide range of different indications for a DMSA scan in this study (different renal size, symptomatic urinary tract infection [UTI], Vesicoureteral reflux (VUR), increase of hydronephrosis, refusal of CIC, or per provider discretion); third, 192 out of the 292 patients did not receive a DMSA scan. Taken together, there is a considerable selection bias which should be taken into account when drawing conclusions from the present data. There may be a non-negligible bias when comparing the group of patients born after 2007 (group 1) with those born