Assessment and investigation

Several signs of catatonia can be elicited through clinical examination. The standardised examination procedure for the Bush Francis Catatonia Rating Scale is recommended for a consistent approach. Click the link to the Bush-Francis Catatonia Rating Scale Assessment Resources , to see how to perform the examination.

A general physical and neurological examination should be carried out. It is advisable to complete an examination for Extra Pyramidal Side Effects using the Abnormal Involuntary Movement Scale (AIMS) procedure if the patient is taking antipsychotic medication.

A Lorazepam challenge test, sometimes referred to as the Lorazepam sedation test, can support the diagnosis. A test dose of Lorazepam is given, followed by a reassessment of catatonic features at 40 minutes. A positive test is indicated by an over 50% reduction in symptoms. The term sedation test refers to the observation that those with catatonia are far less sedated by benzodiazepines than would ordinarily be expected. Many patients will be ‘paradoxically’ be more alert following administration, which can offer further evidence to support the diagnosis.

Investigations in patients with catatonia serve to:

• identify and manage physical health problems irrespective of the catatonia diagnosis
• allow for identification of potential drivers of the catatonia itself
• allow us to exclude any potential differential diagnoses other than catatonia (to an appropriate degree, judged on the basis of the clinical picture and context).

All patients with catatonia should be considered for the following bloods: FBC, U&E’s, LFTs, CK, CRP, TFTs, B12, Folate, Ca2+/Mg2+/Phos, iron studies. This includes a refeeding panel, which is helpful both if there are issues around oral intake, and to compare to if intake drops. It may be useful to make reference to your local refeeding guideline.

Where possible, a urinary drug screen should be obtained. A baseline ECG is useful, and can be repeated if there is an antipsychotic being started/increased, if ECT is being considered, if there is electrolyte disturbance or if there is other/unexplained medical deterioration.

In all patients, careful review of what medications they have been exposed to is important, including those which have been started, had a dose-change, or suddenly stopped.

Other investigations may be indicated: syphilis serology, a Blood Borne Virus screen, NMDA and VGKC antibodies, CT/MRI head, EEG, and Lumbar Puncture (anti-NMDA antibodies are sometimes found only in the CSF beyond the acute stage of NMDA encephalopathy). If choice/appropriateness of certain investigations is felt to be unclear, discussion with neurology or neuropsychiatry may be beneficial.

Paediatric catatonia presents differently in some respects to the classic description in mature/older adults. ‘Withdrawal’ may include food or fluid refusal, for example, and incontinence is not uncommon. Combativeness is more frequently observed.

Those in later life stages more frequently present with catatonic stupor and hypokinetic signs. This patient group are more likely to have a physical health cause/driver of catatonia, and so thorough consideration of investigations is advised. Particular care needs to be taken to delineate from other differentials such as delirium, psychosis, seizure activity, stroke, dementia and coma.

In autism, the terms ‘catatonia-like deterioration in autism’ and ‘autistic catatonia’ are sometimes used. Catatonia may sometimes be a form of stress response in autism, and it is important to identify any psychosocial stressors which have precipitated its development.

There is often more fluctuation in symptoms, with periods of posturing, excitement, and typical function all sometimes observed over short intervals. Echophenomena are common, and care must be taken to distinguish baseline from acute deterioration. Severe self-injurious behaviour may be one manifestation of autistic catatonia and may respond to the same treatments, including ECT.

Manifestations of catatonia in autism may be organised as follows (Shah, 2019):

• Primary difficulties/manifestations – increased slowness, movement difficulties (freezing There is often more fluctuation in symptoms, with periods of posturing, excitement, and typical function all sometimes observed over short intervals. Echophenomena are common, and care must be taken to distinguish baseline from acute deterioration. Severe self-injurious behaviour may be one manifestation of autistic and becoming ‘stuck’), movement abnormalities, prompt dependence, passivity and apparent lack of motivation, posturing, periods of shutdown, catatonic excitement, fluctuations of difficulty.
• Secondary difficulties and autism breakdown – social withdrawal and communication problems, decline in self-help skills, incontinence, ‘challenging’ behaviour, mobility and muscle wastage, physical problems, breakdown.
• Consequences for the individuals and their families – inability to attend school, college or work, or cope with everyday life; stress for families and carers.

Given potential symptom overlap and the risk of diagnostic overshadowing, it is sensible to compare ‘baseline’ and current presentation in each domain of relevance. One such structured tool is the Autism Catatonia Evaluation (ACE-S) (Shah, 2019), a PDF of which is available on the NHS Lothian Catatonia Intranet page .