 This study involves the collection of medical information to create a computer database or registry for patients with PH, Dent disease, cystinuria and APRT deficiency. The information will be entered into the registry by your physician or health care provider. The computer web site for the registry is secure and protected by a required password. Some information which will be entered may include your age at first symptoms of PH,Dent disease, cystinuria or APRT, laboratory values, kidney function and the progress of your health over time. Information for an individual patient can only be viewed by the appropriate physician or staff. Once the information is entered into the registry, you will only be identified by a code number. 