Tardive Dyskinesia - Differential Diagnosis

The differential diagnosis of TD includes hereditary and acquired forms of chorea, primary torsion dystonia, psychogenic movement disorder, the stereotypic movements of schizophrenia, Tourette syndrome, neuroacanthocytosis, hyperthyroidism, attention-deficit/hyperactivity disorder, restless legs syndrome, hypoparathyroidism, systemic lupus erythematosus, and ill-fitting dentures or edentulousness.

Drug-induced parkinsonism manifests with the some of the same symptoms as classic Parkinson's disease—slowness of movement (bradykinesia) and rigidity. Tardive dystonia may appear at any time in the course of treatment with DRAs and up to years afterward; acute dystonia may occur within a few days of exposure. Backward arching of the trunk is primarily seen in acute dystonia; spasmodic torticollis, retrocollis, and internal rotation of the arms, elbow extension, and wrist flexing are characteristic of tardive dystonia. Tardive akathisia usually exists along with tardive dystonia.

The movements of withdrawal emergent syndromes (as described above in the Symptoms section) are brief, jerky, and irregular (choreic). These movements typically flow from one body part to another in a random manner and usually involve the arms, legs, trunk, and neck. These are different than the unusual movements of the mouth and tongue seen in classic TD. In adults, withdrawal dyskinesia may manifest as a transient TD, which typically resolves within 3 months after removal of the neuroleptic agent.

Neuroleptic malignant syndrome is an abrupt, life-threatening response that occurs in approximately 0.2% of patients after they receive a therapeutic dose of a neuroleptic drug. The symptoms include an alarming high body temperature or hyperthermia (> 38°C), muscle rigidity, and problems with a part of the nervous system (autonomic dysregulation) that helps to regulate certain involuntary body functions such as sweating, blood pressure, etc.

	Treatment