U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Search results

Items: 4

1.

Familial hyperkalemic periodic paralysis

Hyperkalemic periodic paralysis (hyperPP) is characterized by attacks of flaccid limb weakness (which may also include weakness of the muscles of the eyes, throat, breathing muscles, and trunk), hyperkalemia (serum potassium concentration >5 mmol/L) or an increase of serum potassium concentration of at least 1.5 mmol/L during an attack of weakness and/or provoking/worsening of an attack by oral potassium intake, normal serum potassium between attacks, and onset before age 20 years. In approximately half of affected individuals, attacks of flaccid muscle weakness begin in the first decade of life, with 25% reporting their first attack at age ten years or older. Initially infrequent, the attacks then increase in frequency and severity over time until approximately age 50 years, after which the frequency of attacks declines considerably. The major attack trigger is eating potassium-rich foods; other triggers include: cold environment; rest after exercise, stress, or fatigue; alcohol; hunger; and changes in activity level. A spontaneous attack commonly starts in the morning before breakfast, lasts for 15 minutes to one hour, and then passes. Individuals with hyperPP frequently have myotonia (muscle stiffness), especially around the time of an episode of weakness. Paramyotonia (muscle stiffness aggravated by cold and exercise) is present in about 45% of affected individuals. More than 80% of individuals with hyperPP older than age 40 years report permanent muscle weakness and about one third develop a chronic progressive myopathy. [from GeneReviews]

MedGen UID:
68665
Concept ID:
C0238357
Disease or Syndrome
2.

Hypokalemic periodic paralysis, type 1

Hypokalemic periodic paralysis (hypoPP) is a condition in which affected individuals may experience paralytic episodes with concomitant hypokalemia (serum potassium <3.5 mmol/L). The paralytic attacks are characterized by decreased muscle tone (flaccidity) more marked proximally than distally with normal to decreased deep tendon reflexes. The episodes develop over minutes to hours and last several minutes to several days with spontaneous recovery. Some individuals have only one episode in a lifetime; more commonly, crises occur repeatedly: daily, weekly, monthly, or less often. The major triggering factors are cessation of effort following strenuous exercise and carbohydrate-rich evening meals. Additional triggers can include cold, stress/excitement/fear, salt intake, prolonged immobility, use of glucosteroids or alcohol, and anesthetic procedures. The age of onset of the first attack ranges from two to 30 years; the duration of paralytic episodes ranges from one to 72 hours with an average of nearly 24 hours. Long-lasting interictal muscle weakness may occur in some affected individuals and in some stages of the disease and in myopathic muscle changes. A myopathy may occur independent of paralytic symptoms and may be the sole manifestation of hypoPP. [from GeneReviews]

MedGen UID:
811387
Concept ID:
C3714580
Disease or Syndrome
3.

Hypokalemic periodic paralysis, type 2

Hypokalemic periodic paralysis (hypoPP) is a condition in which affected individuals may experience paralytic episodes with concomitant hypokalemia (serum potassium <3.5 mmol/L). The paralytic attacks are characterized by decreased muscle tone (flaccidity) more marked proximally than distally with normal to decreased deep tendon reflexes. The episodes develop over minutes to hours and last several minutes to several days with spontaneous recovery. Some individuals have only one episode in a lifetime; more commonly, crises occur repeatedly: daily, weekly, monthly, or less often. The major triggering factors are cessation of effort following strenuous exercise and carbohydrate-rich evening meals. Additional triggers can include cold, stress/excitement/fear, salt intake, prolonged immobility, use of glucosteroids or alcohol, and anesthetic procedures. The age of onset of the first attack ranges from two to 30 years; the duration of paralytic episodes ranges from one to 72 hours with an average of nearly 24 hours. Long-lasting interictal muscle weakness may occur in some affected individuals and in some stages of the disease and in myopathic muscle changes. A myopathy may occur independent of paralytic symptoms and may be the sole manifestation of hypoPP. [from GeneReviews]

MedGen UID:
413748
Concept ID:
C2750061
Disease or Syndrome
4.

Episodic flaccid weakness

Recurrent episodes of muscle flaccidity, a type of paralysis in which a muscle becomes soft and yields to passive stretching. [from HPO]

MedGen UID:
871107
Concept ID:
C4025572
Finding
Format

Send to:

Choose Destination

Supplemental Content

Find related data

Search details

See more...

Recent activity