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ORPHA:2134

Atypical hemolytic uremic syndrome

medium confidenceDisorder

Also known as: Atypical HUS · aHUS

Publications

15,234

96.7th percentile

Trials

25

Interventional, condition-specific

Researchers

1,109

Distinct authors in sample

Gene link

CD46, CFH, CFI

Definitive

Readiness

6/6

Stages with a signal

Clinical definition (Orphanet)

A rare, genetic thrombotic microangiopathy due to dysregulation of the alternative complement pathway and characterized by the triad of hemolytic anemia, thrombocytopenia, and acute renal dysfunction.

How rare: 1-9 / 1 000 000 — roughly one to nine people per million. In a city the size of Kolkata, perhaps a few dozen.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (7)

Atypical Hemolytic Uremic Syndrome · D-HUS · atypical HUS · atypical hemolytic uremic syndrome · hemolytic-uremic syndrome without diarrhea · hemolytic-uremic syndrome without diarrhoea · non-diarrhea-associated hemolytic uremic syndrome

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.”

6/6 stages with a signal

An interventional trial matched this condition name on ClinicalTrials.gov — see trials below.

  1. Gene identifiedPresent

    Definitive — CD46, CFH, CFI, THBD, VTN

  2. LiteraturePresent

    15,234 matched papers (9,168 in last 10 years) Source

  3. Phenotype characterisedPresent

    73 HPO annotations (e.g. Hemolytic-uremic syndrome; Decreased circulating complement C3 concentration; Hematuria) Source

  4. Animal modelPresent

    1 genotype model (Mus musculus) Source

  5. Orphan designationPresent

    3 FDA designations (2 FDA orphan-indication approvals) — e.g. avacopan Source

  6. Interventional trialPresent

    25 matched on ClinicalTrials.gov (6 recruiting in sample)

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?

Yes — we know a specific gene responsible (CD46, CFH, CFI…).

GenCC classification: Definitive.

Phenotypes (Monarch / HPO)

73

Associated phenotypes · MONDO:0016244

  • Hemolytic-uremic syndrome
  • Decreased circulating complement C3 concentration
  • Hematuria
  • Microangiopathic hemolytic anemia
  • Elevated circulating creatinine concentration

Showing 5 of 73 — open Monarch for the full list.

Animal models (Monarch / Alliance)

1

Model associations linked to this Mondo ID

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)

3

Designations · 2 with FDA orphan-indication approval

  • FDA avacopanAtypical Hemolytic Uremic Syndrome · 2014-11-17 · Not FDA Approved for Orphan Indication
  • FDA complement factor HAtypical Hemolytic Uremic Syndrome · 2009-12-07 · Not FDA Approved for Orphan Indication
  • FDA eculizumab (Soliris)Atypical Hemolytic Uremic Syndrome · 2009-04-29

Sources: FDA OOPD · EMA orphan designations

Open Targets candidates

8

Drugs / clinical candidates · MONDO_0016244

CTD chemicals (MyDisease.info)

1 associated chemical · 45 pathways. Therapeutic evidence is listed first when present — not a treatment recommendation.

  • Gemcitabine · marker/mechanism

Pathways: Glycerolipid metabolism; Glycerophospholipid metabolism; Metabolic pathways; Phosphatidylinositol signaling system; Phospholipase D signaling pathway; Phagosome; Complement and coagulation cascades; AGE-RAGE signaling pathway in diabetic complications

MyDisease.info · MONDO:0016244

Literature

Is anyone studying this?

15,234

15,234 papers — among the better-studied rare conditions, though still a fraction of common-disease literature (breast cancer: over 700,000). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

15,234 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).

9,168 in the last 10 years · medium confidence · 96.7th percentile (publications denominator)

Phrase hits: 6,095 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

1,109

Distinct author names in 200 sampled papers — named people below.

Who's working on it?

People publishing on this condition (sampled Europe PMC records). Affiliation is the most recent found in that sample.

  1. 01
    Kato N5 papers · 2026

    Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

    Papers in Europe PMC
  2. 02
    Maruyama S5 papers · 2026

    Department of Nephrology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Nagoya, Aichi, 466-8550, Japan. marus@med.nagoya-u.ac.jp.

    Papers in Europe PMC
  3. 03
    van de Kar NCAJ4 papers · 2026

    Radboud University Medical Center.

    Papers in Europe PMC
  4. 04
    Wang X4 papers · 2026

    Department of Nephrology, Fuyang People's Hospital of Anhui Medical University, Anhui, China.

    Papers in Europe PMC
  5. 05
    Aiello S3 papers · 2026

    Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Clinical Research Center for Rare Diseases Aldo e Cele Daccò and Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy.

    Papers in Europe PMC
  6. 06
    Ardissino G3 papers · 2026

    Center for HUS Prevention, Control and Management, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy. ardissino@centroseu.org.

    Papers in Europe PMC
  7. 07
    Benigni A3 papers · 2026

    Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Clinical Research Center for Rare Diseases Aldo e Cele Daccò and Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy.

    Papers in Europe PMC
  8. 08
    Chaturvedi S3 papers · 2026

    Department of Medicine, Division of Hematology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

    Papers in Europe PMC
  9. 09
    Chen S3 papers · 2026

    Department of Nephrology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China.

    Papers in Europe PMC
  10. 10
    Gastoldi S3 papers · 2026

    Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Clinical Research Center for Rare Diseases Aldo e Cele Daccò and Centro Anna Maria Astori, Science and Technology Park Kilometro Rosso, Bergamo, Italy.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

25

interventional trials for this specific condition

25 interventional trials matched this specific condition name; 6 currently recruiting in our sample. 16 trials are registered for hemolytic-uremic syndrome, the broader category — shown separately because they may or may not enrol this specific subtype.

Data as of 11 September 2026 · last trial check 28 July 2026

25 interventional trials — more than 77.2% of diseases in the trials denominator have none at all (5501 of 7126; this disease is at the 95.5th percentile).

medium confidence · 95.5th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

25 interventional trials matched after quoted-phrase search and title/condition post-filter.

Broader category: hemolytic-uremic syndrome

16

Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.

Worth raising with a clinician. How we count trials.

Recruiting under the broader category

Observational and natural-history studies

14 observational studies match this condition. These do not test a treatment and are not counted in the interventional-trial headline, but they are genuine research: natural-history work often defines the endpoints needed for a future rare-disease trial, and families may be able to enroll.

Recruiting or not-yet-recruiting

Open the complete matched search on ClinicalTrials.gov

General rare disease registries you may be eligible for

These studies enroll across many rare conditions. They are not counted as evidence that anyone is studying this specific disease.

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 10 · after dedupe 9 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 9 · dropped 0 · fetched 2026-07-29

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 (9)

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 Atypical hemolytic uremic syndrome — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

Directly listed under NPRD Group 3.

Group 3 — high-cost / lifelong therapy with careful selection

Up to ₹50 lakh per patient

Financial support at notified Centres of Excellence is the figure commonly cited in recent MoHFW/PIB statements. Many Group 3 patients also use the MoHFW voluntary-contribution / crowdfunding portal.

Eligibility and patient selection rules change. Verify with a CoE; the crowdfunding portal is a separate mechanism from CoE funding. Verify

Centres of Excellence (15)
  • All India Institute of Medical Sciences (AIIMS) — New Delhi, Delhi
  • Maulana Azad Medical College — New Delhi, Delhi
  • Sanjay Gandhi Post Graduate Institute of Medical Sciences — Lucknow, Uttar Pradesh
  • Post Graduate Institute of Medical Education and Research (PGIMER) — Chandigarh, Chandigarh
  • Centre for DNA Fingerprinting & Diagnostics with Nizam’s Institute of Medical Sciences — Hyderabad, Telangana
  • King Edward Memorial Hospital — Mumbai, Maharashtra
  • Institute of Post-Graduate Medical Education and Research (IPGMER) — Kolkata, West Bengal
  • Centre for Human Genetics with Indira Gandhi Hospital — Bengaluru, Karnataka
  • Institute of Child Health and Hospital for Children (ICH & HC) — Chennai, Tamil Nadu
  • All India Institute of Medical Sciences (AIIMS) — Jodhpur, Rajasthan
  • Sree Avittam Thirunal Hospital (SAT), Government Medical College — Thiruvananthapuram, Kerala
  • All India Institute of Medical Sciences (AIIMS) — Bhopal, Madhya Pradesh
  • Regional Institute of Medical Sciences (RIMS) — Imphal, Manipur
  • All India Institute of Medical Sciences (AIIMS) — Patna, Bihar
  • Assam Medical College & Hospital — Dibrugarh, Assam

Voluntary contributions / crowdfunding (separate from CoE funding): https://rarediseases.mohfw.gov.in/

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.

("Atypical hemolytic uremic syndrome" OR "Atypical HUS" OR "D-HUS" OR "hemolytic-uremic syndrome without diarrhea" OR "hemolytic-uremic syndrome without diarrhoea" OR "non-diarrhea-associated hemolytic uremic syndrome") OR ("CD46" OR "CD46 syndrome" OR "CD46-related" OR "CFH syndrome" OR "CFH-related" OR "CFI syndrome" OR "CFI-related")

Run this search on Europe PMC

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Atypical hemolytic uremic syndrome" OR "Atypical HUS" OR "D-HUS" OR "hemolytic-uremic syndrome without diarrhea" OR "hemolytic-uremic syndrome without diarrhoea" OR "non-diarrhea-associated hemolytic uremic syndrome"

Interventional trials matched via: phrase (mesh = registered under a MeSH descriptor no name phrase would catch; recall-expansion = gene / selected parent terms used only for trials).

Study-type breakdown: 25 interventional · 14 observational · 0 expanded access. Only interventional studies enter the trial headline.

Parent-category trials query:

"hemolytic-uremic syndrome"

Query health: ok — strategies attempted: phrase; with hits: phrase

Run this search on ClinicalTrials.gov

Synonyms dropped by stoplist: aHUS

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • 1 synonym(s) dropped by stoplist (may under-count)
  • No label/synonym collisions with other diseases in this corpus

Ingested 2026-07-26T19:13:58.520Z