Essential tremor (ET), also called benign tremor, familial tremor, and idiopathic tremor, is a medical condition characterized by involuntary rhythmic contractions and relaxations (oscillations or twitching movements) of certain muscle groups in one or more body parts of unknown cause. It is typically symmetrical, and affects the arms, hands, or fingers; but sometimes involves the head, vocal cords, or other body parts. Essential tremor is either an action (intention) tremor—it intensifies when one tries to use the affected muscles during voluntary movements such as eating and writing—or it is a postural tremor, present with sustained muscle tone. This means that it is distinct from a resting tremor, such as that caused by Parkinsons disease, which is not correlated with movement.Essential tremor is a progressive neurological disorder, and the most common movement disorder. Its onset is usually after age 40, but it can occur at any age. The cause is unknown. Diagnosis is by observing the typical pattern of the tremor coupled with the exclusion of known causes of such a tremor. While essential tremor is distinct from Parkinsons disease, which causes a resting tremor, essential tremor is nevertheless sometimes misdiagnosed as Parkinsons disease. Some patients have been found to have both essential tremors and resting tremors.Treatments for essential tremor include medications, typically given sequentially to determine which provides the best compromise between effectiveness and troublesome side effects. Clostridium botulinum toxin (Botox) injections and ultrasound are also sometimes used for cases refractory to medications.
Naxos disease (also known as "diffuse non-epidermolytic palmoplantar keratoderma with woolly hair and cardiomyopathy" or "diffuse palmoplantar keratoderma with woolly hair and arrhythmogenic right ventricular cardiomyopathy", first described on the island of Naxos by Nikos Protonotarios) is a cutaneous condition characterized by a palmoplantar keratoderma. The prevalence of the syndrome is up to 1 in every 1000 people in the Greek islands.It has been associated with mutations in the genes encoding the proteins desmoplakin, plakoglobin, desmocollin-2, and SRC-interacting protein (SIP). Naxos disease has the same cutaneous phenotype as the Carvajal syndrome. Symptoms
Between 80 and 99% of those with Naxos disease will display some of the following symptoms:

Disease of the heart muscle
Thickening of palms and soles
Sudden increased heart rate
Dizzy spells
Kinked hair

See also
Olmsted syndrome
List of cutaneous conditions
List of conditions caused by problems with junctional proteins

References


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