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ORPHA:31043

Primary hypomagnesemia with hypercalciuria and nephrocalcinosis without severe ocular involvement

low confidenceSubtype of disorder

Also known as: FHHNC without severe ocular involvement · HOMG3 · Renal hypomagnesemia type 3

Publications

1,058

Trials

0

Interventional, condition-specific

Researchers

48

Distinct authors in sample

Gene link

CLDN16

Definitive

Readiness

5/6

Stages with a signal

Clinical definition (Orphanet)

Familial primary hypomagnesemia with hypercalciuria and nephrocalcinosis without severe ocular involvement (FHHN) is a form of familial primary hypomagnesemia (FPH), characterized by recurrent urinary tract infections, nephrolithiasis, bilateral nephrocalcinosis, renal magnesium (Mg) wasting, hypercalciuria and kidney failure.

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.

Orphanet entry

Cross-references

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

Additional Mondo synonyms (5)

CLDN16 familial primary hypomagnesemia · CLDN16 primary hypomagnesemia · familial primary hypomagnesemia caused by mutation in CLDN16 · primary hypomagnesemia caused by mutation in CLDN16 · renal hypomagnesemia type 3

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.”

5/6 stages with a signal

No specific-condition interventional trial, but broader-category trials exist — discuss eligibility with a clinician.

  1. Gene identifiedPresent

    Definitive — CLDN16

  2. LiteraturePresent

    1,058 matched papers (701 in last 10 years) Source

  3. Phenotype characterisedPresent

    55 HPO annotations (e.g. Short metacarpal; Macroscopic hematuria; Chronic kidney disease) Source

  4. Animal modelPresent

    2 genotype models (Mus musculus) Source

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialPartial

    None under the specific name; 5 for broader category nephrocalcinosis

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 (CLDN16).

GenCC classification: Definitive.

Phenotypes (Monarch / HPO)

55

Associated phenotypes · MONDO:0009550

  • Short metacarpal
  • Macroscopic hematuria
  • Chronic kidney disease
  • Hyperuricosuria
  • Rickets

Showing 5 of 55 — open Monarch for the full list.

Animal models (Monarch / Alliance)

2

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)

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)

7 associated chemicals · 30 pathways. Therapeutic evidence is listed first when present — not a treatment recommendation.

  • Magnesium · therapeutic
  • Potassium · therapeutic
  • Thiazides · therapeutic
  • Capreomycin · marker/mechanism
  • Furosemide · marker/mechanism
  • Lansoprazole · marker/mechanism
  • Tacrolimus · marker/mechanism

Pathways: cGMP-PKG signaling pathway; cAMP signaling pathway; Cardiac muscle contraction; Adrenergic signaling in cardiomyocytes; Cell adhesion molecules (CAMs); Tight junction; Leukocyte transendothelial migration; Insulin secretion

MyDisease.info · MONDO:0009550

Literature

Is anyone studying this?

1,058

1,058 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

1,058 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).

701 in the last 10 years · low confidence

Phrase hits: 9 · MeSH hits: 0

Open Europe PMC search

Who's working on it?

48

Distinct author names in 9 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.

  1. 01
    Katoh M2 papers · 2024

    Department of Global Network, M & M Precision Medicine, Tokyo 113‑0033, Japan.

    Papers in Europe PMC
  2. 02
    Adeerjiang Y1 paper · 2025

    Department of Endocrinology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China.

    Papers in Europe PMC
  3. 03
    Baker MS1 paper · 2016
    Papers in Europe PMC
  4. 04
    Baldini N1 paper · 2019

    Laboratory for Orthopedic Pathophysiology and Regenerative Medicine, IRCCS Istituto Ortopedico Rizzoli, via di Barbiano 1/10, 40136 Bologna, Italy.

    Papers in Europe PMC
  5. 05
    Beavis RC1 paper · 2016

    Department of Biochemistry and Medical Genetics, University of Manitoba , 744 Bannatyne Avenue, Winnipeg, Manitoba R3E 0W3, Canada.

    Papers in Europe PMC
  6. 06
    Bockenhauer D1 paper · 2021

    Department of Renal Medicine, University College London, NW3 2PF, London, UK. d.bockenhauer@ucl.ac.uk.

    Papers in Europe PMC
  7. 07
    Campbell CA1 paper · 2017

    Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA.

    Papers in Europe PMC
  8. 08
    Caudarella R1 paper · 2019

    Maria Cecilia Hospital, GVM Care and Research, Via Corriera 1, 48033 Cotignola (RA), Italy.

    Papers in Europe PMC
  9. 09
    Darbro BW1 paper · 2017

    Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA.

    Papers in Europe PMC
  10. 10
    Denker E1 paper · 2024

    Department of Biological Sciences, University of Bergen, Bergen, Norway.

    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). 5 trials are registered for nephrocalcinosis, the broader category — shown separately because they may or may not enrol this specific subtype.

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.

low 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.

5 interventional trials matched nephrocalcinosis, the broader category — listed below. Those studies are not counted in the condition-specific total.

Broader category: nephrocalcinosis

5

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

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 0 · after dedupe 0 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 0 · 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).

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 Primary hypomagnesemia with hypercalciuria and nephrocalcinosis without severe ocular involvement — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This 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 without severe ocular involvement" OR "FHHNC without severe ocular involvement" OR "HOMG3" OR "Renal hypomagnesemia type 3" OR "CLDN16 familial primary hypomagnesemia" OR "CLDN16 primary hypomagnesemia" OR "familial primary hypomagnesemia caused by mutation in CLDN16" OR "primary hypomagnesemia caused by mutation in CLDN16") OR ("CLDN16" OR "CLDN16 syndrome" OR "CLDN16-related")

Run this search on Europe PMC

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

"Primary hypomagnesemia with hypercalciuria and nephrocalcinosis without severe ocular involvement" OR "FHHNC without severe ocular involvement" OR "HOMG3" OR "Renal hypomagnesemia type 3" OR "CLDN16 familial primary hypomagnesemia" OR "CLDN16 primary hypomagnesemia" OR "familial primary hypomagnesemia caused by mutation in CLDN16" OR "primary hypomagnesemia caused by mutation in CLDN16"

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

Parent-category trials query:

"nephrocalcinosis"

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 (1058) is implausibly high for prevalence class "<1 / 1 000 000" — treat as possible over-matching, not a measure of research intensity

Ingested 2026-07-26T23:26:45.361Z