CHOP has established a research database of data and biological samples of people who have autosomal polycystic kidney disease (ARPKD) or another hepato/renal fibrocystic disease (HRFD). The purpose is to try to learn more about the causes of these diseases. We will collect data from participants' medical records to contribute to the database. Optional blood/saliva or tissue sample may also be collected. Visit arpkdb.org to download the consent or call the CHOP Research Coordinator, Jasmine Jaber at jaberj2@chop.edu.

CKiD is an important research study looking at the health of children, teenagers, and young adults who have kidney problems. This research is being done to identify what factors help kidneys stay healthy, and also to see how kidney problems affect health and well-being. Teenagers and young adults 16-22 years old who have been diagnosed with chronic kidney disease (CKD) may be eligible to join the study. The CKiD study has enrolled approximately 1100 children and teenagers across North America since the study began in 2003. Our goal now is to enroll teenagers and young adults in the study. By doing this we can have a better idea of what happens to kidney function and overall health as someone with childhood chronic kidney disease grows up. This will help provide us with a more complete picture of CKD from childhood through adulthood.

The purpose of this NIH-funded placebo-controlled clinical trial is to determine how well ferric citrate will lower FGF23, correct anemia and iron levels in the blood, and maintain normal levels of phosphate in children with CKD. Chronic Kidney Disease (CKD) is a condition in which the kidney function is decreased. Fibroblast Growth Factor 23 (FGF23) is a hormone that regulates blood phosphate levels. High FGF23 levels are linked with worsening of kidney, bone & heart health. Ferric Citrate is an oral medication that decreases the absorption of dietary phosphate by the gut, lowers FGF23 levels and raises iron stores in the body. Ferric Citrate is approved in adults with CKD but has not yet been studied in children.

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1. The risk of developing nephrotic syndrome
2. The response to treatment of nephrotic syndrome and
3. The risk of recurrence of nephrotic syndrome following kidney transplantation.

1. Clinical diagnosis of nephrotic syndrome
2. Biopsy proven diagnosis of FSGS or MCD and,
3. History of living or deceased donor kidney transplantation

The primary goal of this research study is to see if new types of magnetic resonance imaging (MRI) can be used to measure liver health in children with autosomal recessive polycystic kidney disease (ARPKD) compared to healthy controls. Both children with ARPKD and healthy children, aged 6 years and above can participate.

The purpose of this study is to identify components of a physical activity intervention that are effective and meaningful to teenagers with chronic kidney disease (CKD).

Participants will be assigned to 1 of the 16 study groups and will be asked to wear a Fitbit. Participants will also be given a step count goal, answer questionnaires, and complete hand grip strength assessments.

Participants may also be asked to have one-on-one meetings with an exercise coach.

All visits may be completed remotely.