ORPHA:2196
Primary hypomagnesemia with hypercalciuria and nephrocalcinosis with severe ocular involvement
Also known as: FHHNC with severe ocular involvement · Hypercalciuria-bilateral macular coloboma syndrome · Meier-Blumberg-Imahorn syndrome
Query health: suspect — Only one of 2 strategies returned hits (phrase).
Publications
14
19.9th percentile
Trials
0
Interventional, condition-specific
Researchers
82
Distinct authors in sample
Gene link
CLDN19
Definitive
Readiness
2/6
Stages with a signal
Clinical definition (Orphanet)
Familial primary hypomagnesemia with hypercalciuria and nephrocalcinosis with severe ocular involvement (FHHNCOI) is a form of familial primary hypomagnesemia (FPH), characterized by excessive magnesium and calcium renal wasting, bilateral nephrocalcinosis, renal failure and severe ocular abnormalities.
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:0009548
- MeSH:C536148
- OMIM:248190
- UMLS:C4721891
Additional Mondo synonyms (2)
FHHNCOI · hypercalciuria-bilateral macular coloboma 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.”
2/6 stages with a signal
No matched interventional trial; the gene is known and literature exists — preclinical or natural-history work may still be the practical next step.
- Gene identifiedPresent
Definitive — CLDN19
- LiteraturePresent
14 matched papers (5 in last 10 years) Source
- Phenotype characterisedNot checked
Not yet enriched from Monarch / HPO
- Animal modelNot checked
Not yet enriched from Monarch / Alliance
- Orphan designationNot checked
FDA/EMA orphan-drug designation not enriched yet
- 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?
Yes — we know a specific gene responsible (CLDN19).
GenCC classification: Definitive.
Phenotypes (Monarch / HPO)
Not enriched in this build — Monarch phenotype joins were not run for this record.
Animal models (Monarch / Alliance)
Not enriched in this build.
Literature
Is anyone studying this?
14
14 papers have ever been indexed 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=5449) is 41.
14 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 41 (publications denominator n=5449).
5 in the last 10 years · high confidence · 19.9th percentile (publications denominator)
Phrase hits: 14 · MeSH hits: 0
Who's working on it?
82
Distinct author names in 14 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.
- 01Ariceta G2 papers · 2013Papers in Europe PMC
- 02Claverie-Martín F2 papers · 2015
Unidad de Investigación, Hospital Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain. fclamar@gobiernodecanarias.org
Papers in Europe PMC - 03García-Nieto V2 papers · 2015
Unidad de Nefrología Pediátrica, Hospital Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain.
Papers in Europe PMC - 04Vargas-Poussou R2 papers · 2015
Département de Génétique, Hôpital Européen Georges Pompidou, Paris, France.
Papers in Europe PMC - 05Abassi Z1 paper · 2008Papers in Europe PMC
- 06Adelman RA1 paper · 2019
2Department of Ophthalmology, Yale University, 40 Temple Street, New Haven, CT USA.
Papers in Europe PMC - 07Andreazzoli M1 paper · 2021
Department of Biology, University of Pisa, 56127 Pisa, Italy.
Papers in Europe PMC - 08Angeloni D1 paper · 2021
Institute of Life Sciences, Scuola Superiore Sant'Anna, 56124 Pisa, Italy.
Papers in Europe PMC - 09Antón-Gamero M1 paper · 2013Papers in Europe PMC
- 10Avila A1 paper · 2013Papers 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 27 July 2026
No matched interventional trials. This is true for 73% of diseases in the trials denominator (5114 of 7003). Here are the researchers publishing on it.
high confidence · 36.5th 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.
Where to find support
We do not yet link condition-specific patient organisations. These umbrella groups support undiagnosed and ultra-rare families:
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.
"Primary hypomagnesemia with hypercalciuria and nephrocalcinosis with severe ocular involvement" OR "FHHNC with severe ocular involvement" OR "Hypercalciuria-bilateral macular coloboma syndrome" OR "Meier-Blumberg-Imahorn syndrome" OR "FHHNCOI"
ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):
"Primary hypomagnesemia with hypercalciuria and nephrocalcinosis with severe ocular involvement" OR "FHHNC with severe ocular involvement" OR "Hypercalciuria-bilateral macular coloboma syndrome" OR "Meier-Blumberg-Imahorn syndrome" OR "FHHNCOI" OR "CLDN19" OR "familial primary hypomagnesemia with hypercalciuria and nephrocalcinosis"
Recall-expansion terms: CLDN19, familial primary hypomagnesemia with hypercalciuria and nephrocalcinosis
Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.
Query health: suspect — strategies attempted: phrase, recall-expansion; 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
Ingested 2026-07-26T19:25:47.919Z