IllnessParalysis, hypocaliaemic periodic; differential diagnosis

NGS +

[Sanger]

Hypokalemic periodic paralysis causes episodes of extreme muscle weakness that typically begin in childhood or adolescence. These episodes make it impossible to move arms and legs for hours and days. Such episodes occur almost daily, weekly, monthly or more rarely. The seizures can begin without warning or can be triggered by rest after exercise, viral diseases or certain medications. Although people usually regain muscle strength between seizures, some develop persistent muscle weakness as the seizures progress. Hypokalemic periodic paralysis is inherited as autosomal dominant trait with reduced penetrance. Almost 30% of cases cannot currently be resolved by molecular genetics, so that an inconspicuous genetic finding does not mean that the clinical suspected diagnosis is excluded.

Reference: https://www.ncbi.nlm.nih.gov/books/NBK1338/

• Allelic: Alternating hemiplegia of childhood 1 (ATP1A2)
• Allelic: Atrial fibrillation, familial, 9 (KCNJ2)
• Allelic: Hyperkalemic periodic paralysis, type 2 (SCN4A)
• Allelic: Migraine, familial basilar (ATP1A2)
• Allelic: Migraine, familial hemiplegic, 2 (ATP1A2)
• Allelic: Short QT syndrome 3 (KCNJ2)
• Andersen(-Tawil) syndrome (KCNJ2)
• Hypokalaemic periodic paralysis [panelapp] (ATP1A2)
• Hypokalemic periodic paralysis type 1 (CANA1S)
• Hypokalemic periodic paralysis, type 2 (SCN4A)
• Thyrotoxic periodic paralysis, susceptibility to, 2 (KCNJ18)