ORPHA:99734
Myotonia fluctuans
Synonyms: Exercise-induced delayed-onset myotonia · Fluctuating myotonia
- Type
- Disease
- Group
- Disorder
- Inheritance
- Autosomal dominant
- Age of onset
- Childhood
- Status
- active
A form of potassium-aggravated myotonia (PAM) which is cold insensitive, dramatically fluctuating and profoundly worsened by potassium ingestion.
1
Names in Orphadata languages
12 of 12 languages| Lang | Name | Synonyms |
|---|---|---|
| en | Myotonia fluctuans | Exercise-induced delayed-onset myotonia · Fluctuating myotonia |
| fr | Myotonie fluctuante | |
| de | Myotonia fluctuans | |
| es | Miotonía fluctuante | Miotonía de inicio tardío inducida por el ejercicio |
| it | Miotonia fluctuans | Miotonia fluttuante · Miotonia indotta dall'esercizio a esordio ritardato |
| nl | Myotonia fluctuans | Fluctuerende myotonie · Vertraagd optredende inspanningsgeïnduceerde myotonie |
| pt | Miotonia fluctuans | |
| pl | Miotonia z objawami zmiennymi | Miotonia indukowana wysiłkiem o opóźnionym początku |
| cs | Myotonia fluctuans | Fluktuující myotonie · Cvičením vyvolaná myotonie s opožděným nástupem |
| uk | Міотонія флюктуюча | Міотонія сповільненого типу, спричинена фізичним навантаженням · Флуктуаційна міотонія |
| zh | 肌强直波动状态 | 运动型迟发性肌强直 |
| tr | Miyotoni fluktuanları | Değişken miyotoni · Egzersiz kaynaklı gecikmiş başlangıçlı miyotoni |
Definition in:
2
Cross-references
qualifier = Orphanet mapping relation| Source | Code | Qualifier | ICD relation | Validation |
|---|---|---|---|---|
| OMIM | 608390 | NTBT | validated | |
| ICD-10 | G71.1 | NTBT | attributed | validated |
| ICD-11 | 8C71.2 | NTBT | index | validated |
| MONDO | 0020481 | E | validated | |
| UMLS | C0752355 | E | validated |
E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.
3
Classification
Preferential parent (Orphanet linearisation):
Parents in the classifications (1):
- ORPHA:612Potassium-aggravated myotonia
rare genetic diseases; rare neurological diseases
No children.
4
Genes
1 direct| Gene | Association | Status | HGNC | Ensembl | OMIM | Locus | Name | Source of validation |
|---|---|---|---|---|---|---|---|---|
| SCN4A | Disease-causing germline mutation(s) in | Assessed | HGNC:10591 | ENSG00000007314 | 603967 | 17q23.3 | sodium voltage-gated channel alpha subunit 4 | 7980103[PMID]_8308722[PMID] |
5
Prevalence and incidence
1 record| Type | Class | Value | Area | Qualification | Validation | Source |
|---|---|---|---|---|---|---|
| Point prevalence | Unknown | — | Worldwide | Class only | Not yet validated | ORPHANET |
Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.
6
HPO phenotypes
22 annotations · validated 2021-02-12| HPO | Term (as annotated by Orphanet) | Diagnostic |
|---|---|---|
| Very frequent (99-80%) | ||
| HP:0100284 | EMG: myotonic discharges | |
| HP:0003552 | Muscle stiffness | |
| Frequent (79-30%) | ||
| HP:0008967 | Exercise-induced muscle stiffness | |
| HP:0012902 | Myotonia of the lower limb | |
| HP:0012903 | Myotonia of the upper limb | |
| HP:0002491 | Spasticity of facial muscles | |
| Occasional (29-5%) | ||
| HP:0000622 | Blurred vision | |
| HP:0000651 | Diplopia | |
| HP:0012378 | Fatigue | |
| HP:0012899 | Handgrip myotonia | |
| HP:0003326 | Myalgia | |
| HP:0012900 | Myotonia of the face | |
| Very rare (<4-1%) | ||
| HP:0002104 | Apnea | |
| HP:0030842 | Choking episodes | |
| HP:0001288 | Gait disturbance | |
| HP:0025425 | Laryngospasm | |
| HP:0003740 | Myotonia with warm-up phenomenon | |
| HP:0001319 | Neonatal hypotonia | |
| HP:0003701 | Proximal muscle weakness | |
| HP:0000486 | Strabismus | |
| HP:0010307 | Stridor | |
| Excluded (0%) | ||
| HP:0012904 | Cold-sensitive myotonia | |
Run the differential on the 2 obligate / very frequent terms
Annotation source: 30341599[PMID]_32270509[PMID]
7
Sources for this card
- Orphanet page: orpha.net/en/disease/detail/99734
- This record as JSON: /data/d/99734.json