To the editor,

We have read the article entitled ‘Ultrasound-Guided Percutaneous Nephrostomy Performed on Neonates and Infants Using a “14-4” (Trocar and Cannula) Technique’ [1] with great interest since we are particularly interested in percutaneous nephrostomy for neonates or infants. The novelty of the technique and its applicability even at the bedside are remarkable.

In Table 1, indications of the procedure are classified into three groups as UPJ obstruction, UVJ obstruction, and hydroureteronephrosis. We think it would be more appropriate to include UVJ obstruction in the hydroureteronephrosis category as it is one of the etiologies of hydroureteronephrosis.

We noticed that the grades of hydronephrosis are not mentioned; thus, it is difficult to decide if the technique is appropriate for cases with mild dilatation.

It is stated that the median duration of PCN catheter was 75 days, whereas there is one case in which the catheter was maintained for 138 days. We were however a little doubtful whether a catheter with such a small caliber would work for this long without clogging considering the fact that percutaneous nephrostomy catheters should be changed every 3 months to prevent tube obstruction [2, 3]. Besides, 138 days is a quite long period of time for a catheter since they must be exchanged more frequently due to infection risk.