diseases diagnosis

Dystonia: causes and diagnosis

Movement disorder

As can be guessed from the complexity of kinetic disorder, the search for causal factors attributed to dystonia represents an almost complex task, a rather intricate enigma that must be solved, considering the hypothesis of a possible evolution of the disease and its complication. However, only by digging at the root of the problem will it be possible to identify the risk factors and the causes responsible for the dystonic event: in fact, by identifying the causes a correct and indisputable diagnosis can be drawn up, so as to be able to direct the patient towards the most suitable therapies.

In this article, we will discuss the etiopathological factors and the possible diagnostic strategies for drawing up a patient's medical history; in the next concluding article the possible therapeutic options that can be implemented for the resolution of dystonia will instead be addressed.


In some publications of Dystonia Medical Research Foundation ( DMRF ), it is evident that, often, the causes related to the manifestation of dystonia are not detectable: the researchers have not yet succeeded in identifying which biochemical process triggers the dystonic symptomatology. Therefore, we will have to wait a few more years to ascertain precisely the aforementioned "mechanism of dystonia", a hypothetical common thread of all dystonic forms.

Currently, the research has reached some interesting conclusions: it is established that dystonia could be a consequence of both traumas and the intake of particular pharmacological substances for long periods (neuroleptics-antipsychotics). Furthermore, there is no doubt that the mutation of some genes (eg DYT1) may also be responsible for dystonic manifestations; however, despite the aforementioned causal explanations, neither the real origin of the dystonic disorder has been proven, nor what happens inside the body to cause symptoms. [taken from www.dystonia-foundation.org]

Based on the causal factor, dystonic forms are classified into:

  • primary dystonia (dystonic symptoms are the only neurological signs of the disease, which occur most of the time only with tremor)
  • secondary dystonia (the causes reside in: neoplasias, intake of some neuroleptic drugs, stroke etc.)
  • dystonia plus (myoclonic dystonia and DOPA-responsive dystonia: they are characterized by additional neurological disorders that are much more disabling than primary dystonia).

From this classification it can be deduced, therefore, that also other pathologies of the nervous system can cause dystonia; these include strokes, tumors, multiple sclerosis, head trauma, bacterial infections, neonatal brain damage, etc.

Finally, in some subjects suffering from dystonia, the causes of origin reside in hereditary diseases that affect some areas of the nervous system (heredegenerative pathologies) [taken from www.distonia.it]


Currently, doctors do not have a unique and standard diagnostic test to confirm the hypothesis of an alleged dystonia; the clinical evaluation of the patient allows to observe and verify the symptoms of the dystonic form, such as to obtain a complete, albeit initial, clinical diagnosis of the affected subject. First, the doctor must know the patient's history and investigate any family illnesses; after that, the specialist can prescribe some laboratory investigations (eg urine, blood and cerebrospinal fluid analysis).

Moreover, the doctors have a diagnostic instrumentation useful to exclude some forms of disease (eg secondary dystonia), such as the cerebral RMN (Brain Magnetic Resonance) and CT ("image diagnosis", computerized tomography, able to reproduce body areas of the patient three-dimensionally, through X-rays) and diagnostic instruments known as neuroimaging.

Furthermore, the spread of nerve impulses between adjacent muscles and the concomitant activation of agonist and antagonist muscles is diagnosed by an electromyographic investigation of muscle activity (EMG); electromyography is an important diagnostic tool, useful for identifying the muscles involved in the disease, which is essential for the most appropriate therapeutic choice. For cases of dystonic severity, it is possible to use the diagnostic test of molecular genetics.

In any case, in order to draw up a correct diagnosis, the specialist (in general, the neurologist) must be able to identify all the signs and symptoms of the kinetic disorder, in addition to identifying the possible causes, whenever possible. [taken from www.dystonia-foundation.org]