DEFINITION

Catatonia is a syndrome characterized by disturbances in volitional movement and language in the absence of weakness or dysphasia. There is a wide range of nonspecific signs and symptoms that may be elicited:[1][2][3]

• Catatonic stuper--mutism, immobility, nonresponsiveness to pain (with normal alertness)
• Catatonic excitement--purposeless, agitated, disorganized overactivity
• Mannerisms--odd or exaggerated actions
• Echophenomena
  • Echolalia, echopraxia--repetition or imitation of the utterances and/or actions of others
  • Stereotypy--repetitive movement without a goal, e.g. rocking back and forth, tapping hands or feet, verbigeration (repeating the same phrase/sentence like a broken record)
• Paratonia
  • Gegenhalten--resistance to passive motion that is proportional to the magnitude of the external force but increases with the speed of the external force (also called waxy flexibility)
• Mitgehen aka passive obedience (passive motion in any direction brought on by very little external force, test: ask patient to extend the arm, apply pressure to the palm with one finger while instructing "Don’t raise your arm"), automatic obedience (cooperation with illogical requests, test: examiner extends hand while saying "Don’t shake my hand")
• Negativism (resistance to following simple commands OR doing the opposite of what is asked OR not responding to commands)
• Ambitendency (alternating between opposing movements, e.g. walking toward and then withdrawing from the door as if unable to decide whether to leave the room or stay)
• Malignant catatonia is a syndrome very similar to NMS but which was first described in 1832 (some consider NMS to be a form of drug-induced catatonia) featuring: acute onset, fever, abnormal blood pressures, tachycardia, and tachypnea[1]
• There are multiple rating scales that may help in the diagnosis of catatonia, including the Bush-Francis Catatonia Rating Scale[4] which takes about 5 minutes and may be sensitive to changes in symptom severity after treatment.[5][6] However, such rating scales may generate overdiagnosis of catatonia if the threshold for case diagnosis (i.e. the number of symptoms required for diagnosis) is set too low.
• The classification of catatonia has been a point of contention since its original formulation in 1870s. In DSM-V it is recognized as a separate clinical entity (catatonia due to a specific medical or neurological disorder) as well as as a specifier for severe mood disorders (Major Depressive Disorder, Bipolar Disorder) and Schizophrenia.[7]