Isaac syndrome

Summary

Isaac syndrome (MONDO:0019399) is a disease. A subtype of muscular channelopathy — broader associated-gene and molecular evidence is on the parent page (see Disease family below).

At a glance

• Prevalence: <1 / 1 000 000 (Worldwide) [Orphanet-validated]
• Phenotypes (HPO): 13

Clinical features

Epidemiology

Prevalence records

2 prevalence record(s), Orphanet:

Type	Class	Value	Geography	Validation
Cases/families		150	Worldwide	Validated
Point prevalence	<1 / 1 000 000		Worldwide	Validated

Signs & symptoms

Clinical features (HPO)

13 HPO clinical features (Orphanet curated; top 13 by frequency):

HPO ID	Term	Frequency
HP:0000975	Hyperhidrosis	Frequent (30-79%)
HP:0001824	Weight loss	Frequent (30-79%)
HP:0002353	EEG abnormality	Frequent (30-79%)
HP:0002380	Fasciculations	Frequent (30-79%)
HP:0002411	Myokymia	Frequent (30-79%)
HP:0003394	Muscle spasm	Frequent (30-79%)
HP:0003552	Muscle stiffness	Frequent (30-79%)
HP:0008981	Calf muscle hypertrophy	Frequent (30-79%)
HP:0010546	Muscle fibrillation	Frequent (30-79%)
HP:0100288	EMG: myokymic discharges	Frequent (30-79%)
HP:5000005	Anti-CASPR2	Frequent (30-79%)
HP:0002936	Distal sensory impairment	Occasional (5-29%)
HP:0001324	Muscle weakness	Very rare (<1-4%)

Identifiers

Disease identifiers

Field	Value
Canonical name	Isaac syndrome
Mondo ID	MONDO:0019399
Orphanet	84142
ICD-11	646523932
SNOMED CT	305719002
UMLS	C0242287
MedGen	116151
GARD	0006793
Is cancer (heuristic)	no

Also known as: acquired neuromyotonia · continuous muscle fiber activity syndrome · continuous muscle fibre activity syndrome · Isaac’s-Merten’s syndrome · Isaac-Mertens syndrome · Isaacs’ syndrome · neuromyotonia · peripheral nerve hyperexcitability · Quantal squander syndrome

Disease family

This is a subtype of muscular channelopathy. Genetic, therapeutic, and trial evidence is largely curated at the broader-term level — see the parent page for the associated-gene cohort and molecular evidence.

Classification path: disease › human disease › disease by body system or component › nervous system disorder › neuromuscular disease › muscular channelopathy › Isaac syndrome

Related subtypes (11): Andersen-Tawil syndrome, Morvan syndrome, Thomsen and Becker disease, malignant hyperthermia of anesthesia, RYR1-related myopathy, CNGB3-related retinopathy, SCN4A-related channelopathy, neurological muscular channelopathy due to a genetic sodium channel defect, neurological muscular channelopathy due to a genetic chloride channel defect, neurological muscular channelopathy due to a genetic calcium channel defect, neurological muscular channelopathy due to a genetic potassium channel defect

Genetics & variants

GWAS landscape

No GWAS associations recorded — common-variant (GWAS) studies don’t cover this disease (typical for Mendelian / rare diseases). See the curated gene cohort and Mendelian overlap below.

Variant details and genetic-evidence tiers

No tiered GWAS variants or ClinVar records for this disease.

Genes & proteins

No associated-gene cohort resolved for this disease. Atlas builds the molecular and therapeutic sections — associated genes, protein families, druggability, pathways, interactions, and drug associations — by aggregating over a disease’s associated genes (resolved via GWAS / GenCC / ClinVar / CIViC), and none resolved here. This is expected for antibody-mediated, autoimmune, or otherwise non-gene-defined conditions; the curated evidence for this disease is its clinical features, GWAS susceptibility, and clinical trials (above).

Function

No pathway enrichment — requires an associated-gene cohort.

Therapeutics

No druggable-target or therapeutic data for this disease’s cohort.

Clinical trials & evidence

Clinical trials

Clinical trials: 0.