To the Editor.— The article by Jenny et al (240:1378, 1978) leaves me with some disquieting questions and comments. The case discussed was that of a paraplegic man with bilateral renal calculi who, after conservative with renal pelvic irrigation to dissolve obstructing calculi, had development of severe respiratory depression from hypermagnesemia. This was suspected to be the result of the absorption of the irrigating solution from the renal pelvis. The ability to dissolve retained stone fragments in a safe and effective fashion after incomplete surgical removal was presented by Nemoy and Stamey inThe Journal(215:1470, 1971). However, in that article as well as a subsequent publication in the Journal of Urology , 1 the aforementioned authors stated clearly that an absolute contraindication to the use of irrigation management for retained stone fragments is the presence of a urinary tract infection. There was a clearly described protocol, consisting of a