The Rare Kidney Stone Consortium was established to facilitate cooperative exchange of information among clinicians, patients and investigators to improve care and outcome for patients with rare stone diseases. If you or a family member is affected by APRT Deficiency, we would like your help! Please contact us at rarekidneystones@landspitali.is to participate in the International APRT Deficiency/Dihydroxyadeninuria Registry. The International APRT Deficiency Registry has been established by the Rare Kidney Stone Consortium. Information collected in this registry will increase clinical and research-based understanding of the disease in a manner that no single center could do alone.