ORPHA:652528
Supernumerary kidney
Also known as: Accessory kidney
Publications
233
52.9th percentile
Trials
0
Interventional, condition-specific
Researchers
768
Distinct authors in sample
Gene link
—
Readiness
1/6
Stages with a signal
Clinical definition (Orphanet)
A rare non-syndromic renal/urinary tract characterized by the presence of more than two kidneys (up to five), each of which mostly has its own collecting system, vascular supply, and distinct encapsulated parenchyma. The additional kidney(s), smaller than native ones, mostly occurs ipsilateral and caudal to the left kidney and may be fused to the native kidneys. Patients are usually asymptomatic but they may present with symptoms such as pain, a palpable abdominal mass, fever and sometimes with urinary symptoms (such as urinary incontinence) when supernumerary kidneys occur with an ectopic ureter. Additional abnormalities including horseshoe kidney , ventricular septal defect, and cloacal abnormalities (such as urethral atresia, vaginal atresia, ectopic ureter implantation, imperforate anus, and duplication of urethra) may also be present in some patients.
How rare: <1 / 1 000 000 — fewer than one in a million. In a city the size of Kolkata, that might mean on the order of fifteen people.
Cross-references
Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.
- MONDO:0958093
- UMLS:C5925122
Research stages
Trial readiness signals
Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”
1/6 stages with a signal
Research-stage checklist from open sources (GenCC, literature, Monarch when enriched, ClinicalTrials.gov). Not a prognosis or care recommendation.
- Gene identifiedNot found
No GenCC disease–gene assertion in this build
- LiteraturePresent
233 matched papers (73 in last 10 years) Source
- Phenotype characterisedNot found
No HPO disease–phenotype associations via Monarch for these Mondo IDs
- Animal modelNot found
No Alliance genotype “model of” associations via Monarch for these Mondo IDs
- Orphan designationNot found
No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source
- Interventional trialNot found
No matched interventional trial under our ClinicalTrials.gov rules
Biology
Genes and phenotypes
Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.
Do we know what causes it?
Not yet — the cause hasn't been pinned down in GenCC.
No strong gene–disease assertion joined for this Orphanet entity.
Phenotypes (Monarch / HPO)
None returned for this Mondo ID. That often means “not linked under this ID,” not “no clinical features.”
Animal models (Monarch / Alliance)
None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.
Monarch fetch 2026-07-29
Therapies
Designations, candidates, and chemicals
FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.
Orphan designation (FDA · EMA)
No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.
Open Targets candidates
No drugs or clinical candidates returned for this Mondo ID on Open Targets.
CTD chemicals (MyDisease.info)
No CTD chemical associations returned for this Mondo ID.
Literature
Is anyone studying this?
233
233 papers have ever been published on this condition (under this name). For scale, breast cancer has over 700,000. Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.
233 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).
73 in the last 10 years · medium confidence · 52.9th percentile (publications denominator)
Phrase hits: 233 · MeSH hits: 0
Who's working on it?
768
Distinct author names in 200 sampled papers — named people below.
Who's working on it?
No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.
- 01Garne E4 papers · 2023
Pediatric Department, Hospital Lillebaelt, Kolding, Denmark.
Papers in Europe PMC - 02Loane M4 papers · 2023
EUROCAT Central Registry, University of Ulster, Ulster, Northern Ireland.
Papers in Europe PMC - 03
- 04Kumar S3 papers · 2022
Department of Radiodiagnosis, Kasturba Medical College, Manipal University, Manipal, Karnataka, India.
Papers in Europe PMC - 05Rankin J3 papers · 2022
Institute of Health & Society, Newcastle University, Newcastle upon Tyne, UK.
Papers in Europe PMC - 06Rissmann A3 papers · 2023
Malformation Monitoring Centre Saxony-Anhalt, Otto-von-Guericke University, Magdeburg, Germany.
Papers in Europe PMC - 07Tan J3 papers · 2023
Population Health Research Institute, St George's University of London, London, UK.
Papers in Europe PMC - 08BACON SK2 papers · 1947Papers in Europe PMC
- 09Ballardini E2 papers · 2023
Neonatal Intensive Care Unit, Paediatric Section, IMER Registry (Emilia Romagna Registry of Birth Defects), Department of Medical Sciences, University of Ferrara, Ferrara, Italy.
Papers in Europe PMC - 10Barisic I2 papers · 2021
Children's Hospital Zagreb, University of Zagreb School of Medicine, Zagreb, Croatia.
Papers in Europe PMC
Clinical research
Is a treatment being tested?
0
interventional trials for this specific condition
No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).
Data as of 11 September 2026 · last trial check 11 September 2026
No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.
medium confidence · 38.6th percentile (trials denominator)
Recruiting interventional trials
From the matched ClinicalTrials.gov set
No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.
See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.
Other registries (secondary)
Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.
raw 1 · after dedupe 1 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 1 · dropped 0 · fetched 2026-07-30
Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri
No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).
Uncertain / not reviewed (1)
Where to find support
Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.
Orphanet entry for Supernumerary kidney — check Associations / patient organisations on that page.
India — NPRD
Last verified 2026-07-26This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.
Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.
How we counted this
Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.
"Supernumerary kidney" OR "Accessory kidney"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Supernumerary kidney" OR "Accessory kidney"
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: ok — strategies attempted: phrase; with hits: phrase
Run this search on ClinicalTrials.gov
Confidence reasoning
- Preferred label is multi-word and distinctive
- No synonyms dropped by stoplist
- No label/synonym collisions with other diseases in this corpus
- Publication count (233) is high for prevalence class "<1 / 1 000 000" — confidence capped at medium
Ingested 2026-07-27T19:56:58.184Z