Makindo Medical Notes.com

Related Subjects:Hyperkalaemia |ECG - Hyperkalaemia |Hypokalemia |Hyperkalaemic and Hypokalaemic Periodic Paralysis |Resuscitation - Advanced Life Support

This autosomal dominant disorder is actually due to a disorder of the gene coding for a voltage-gated calcium channel. Classically a generalised weakness comes on after a heavy meal. A family history may be present involving a parent or siblings. Provocation test with oral glucose and assess response to potassium.

About

• Commonest type of Periodic Paralysis syndrome and is inherited as an Autosomal dominant
• Disorder of the gene coding for a voltage gated calcium channel.

Aetiology

• Association with thyrotoxicosis and it is seen more commonly in those from Southeast Asia

Precipitant and Reliever

• K⁺ lowering diuretics can cause weakness.
• Meals high in carbohydrates or sodium can cause weakness.
• IV glucose or IV saline as this will worsen the weakness.
• Attacks relieved by Potassium supplementation.

Clinical

• Classically a generalised weakness comes on after a heavy meal.
• May present from teenage years and tends to improve later in life
• Weakness may even include swallowing and other bulbar features.
• The weakness may last several hours.
• A family history may be present involving a parent or siblings.
• Often comes on in the early morning or after resting following exertion

Investigations

• The [K⁺] is usually < 3.0 mmol/l.
• Genetic studies

Management

• Patients should take a low-carbohydrate, low-sodium diet and know the consequences of intense exercise.
• Acetazolamide can reduce attacks and triamterene and spironolactone have been used