This is a retrospective and prospective, multicenter observational quality improvement study and research registry. Infants undergoing renal replacement therapy utilizing CARPEDIEM for hemodialysis will be enrolled in the study for observation. There are two arms to this study, one for quality improvement and one for research purposes. Patients enrolled in this study have the option to participate additionally in either biospecimen collection, long term follow up after CARPEDIEM, or both. Urine specimen will be collected from fresh voids, but all blood specimen will be obtained from residual clinical specimen. Investigators hope to gain more information into use, treatment course, and outcomes from infants requiring treatment with the CARPEDIEM device.
