Nephropathic cystinosis has been known for well over a hundred years but not until the end of the last century was its molecular defect discovered. Mutations in cystinosin that prohibit egress of cystine from within lysosomes is an underlying genetic defect in all patients, and when untreated, leads to terminal kidney failure and disruptions in most other organ functions including eyes, the brain, endocrine glands, muscles, bone, heart, lung, and linear growth. Well over 100 mutations in cystinosis have been described.

The objective of the KDIGO Controversies Conference on Nephropathic Cystinosis was to gather a global panel of clinical and scientific experts to address key issues related to the cell and molecular biologic consequences of cystinosin deficiency, establish the optimal diagnostic workup to arrive at the diagnosis of nephropathic cystinosis early in life or recognize its later-age presentations, and discuss the unique aspects of management and treatment in the child, adolescent, and adult years. It is hoped that assessing our current state of knowledge will not only improve the characterization of nephropathic cystinosis but will also facilitate communication between researchers and inform clinicians of the evidence base for present treatment options. This conference will also put forth a summary of the outstanding knowledge gaps and propose a research agenda.

Drs. Craig B Langman (Feinberg School of Medicine, Northwestern University, Lurie Children’s Hospital of Chicago, Chicago IL, USA) and Elena Levtchenko (University Hospitals Leuven & Katholieke Universiteit Leuven, Belgium) co-chaired this conference.