QuestionSBA
QuestionChoice
Although the patient describes hallucinations and delusions, the mixed picture and acuity following a physical health illness, especially in elderly patients is more suggestive of a delirium.
10015865
e
Acute psychosis
QuestionChoice
This case describes a mixed delirium with hyperactive features of agitation and hypoactive features such as withdrawing and appearing apathetic. The delirium may have been triggered by the infection, change in environment or due to pain or medications.
10015861
a
Delirium
QuestionChoice
Lewy body dementia is associated with long term cognitive decline, parkinsonism and fluctations in cognition. This presentation is too acute and the lability is not in keeping with LBD.
10015864
d
Lewy Body dementia
QuestionChoice
Bipolar disorder is defined by periods of depression (lasting at least 2 weeks) and mania as opposed to intense emotional lability within a matter of days, there is additionally no mention of a psychiatric history.
10015863
c
Bipolar disorder
QuestionChoice
Although EUPD may cause emotional lability and intense mood swings, there is nothing to suggest a long term psychiatric history in this patient and his presentation has arisen over the last few days due to physical health problems.
10015862
b
Emotionally unstable personality disorder
Concept
Chapter
# Summary

Delirium, also known as acute confusional state, is a frequent condition, primarily observed among elderly individuals. It manifests through symptoms such as disorientation, hallucinations, inattention, memory problems, mood or personality changes, and disturbed sleep. Comprehensive investigation includes physical examination and infection screen. Management focuses on treating the underlying cause, optimising the patient's environment, and, in severe cases, considering sedative measures.

# Definition

Delirium is an acute and fluctuating disturbance in attention and cognition, often accompanied by a change in consciousness. It is typically reversible and frequently seen in the elderly, particularly in inpatient settings. It manifests in three subtypes:

* **Hyperactive** Delirium: Marked by increased psychomotor activity, restlessness, agitation, and hallucinations.
* **Hypoactive** Delirium: Characterised by lethargy, reduced responsiveness, and withdrawal.
* **Mixed** Delirium: Combines features of both hyperactive and hypoactive delirium.

# Epidemiology

Delirium is a common condition, predominantly affecting elderly people, and is seen in up to 30% of elderly inpatients. The incidence increases with age, severity of illness, and the presence of pre-existing cognitive impairment.

# Aetiology

The causes of delirium can be multifactorial and are remembered using the mnemonic DELIRIUMS:

- D: Drugs and Alcohol (Anti-cholinergics, opiates, anti-convulsants, recreational)
- E: Eyes, ears and emotional disturbances
- L: Low Output state (Myocardial Infarction, Acute Respiratory Distress Syndrome, Pulmonary Embolism, Congestive Heart Failure, Chronic Obstructive Pulmonary Disease)
- I: Infection
- R: Retention (of urine or stool)
- I: Ictal (related to seizure activity)
- U: Under-hydration/Under-nutrition
- M: Metabolic disorders (Electrolyte imbalance, thyroid disorders, Wernicke's encephalopathy)
- (S): Subdural hematoma, Sleep deprivation

# Signs and Symptoms

Delirium can present in a number of different ways, including:

- Disorientation
- Hallucinations - visual or auditory
- Inattention
- Memory problems
- Change in mood or personality. **Sundowning** is agitation and confusion worsening in the late afternoon or evening.
- Disturbed sleep

Patients may be hypoactive (sedated) or hyperactive (very agitated), and these presentations can fluctuate over time. Hyperactive delirium is easily seen due to the presentation, while hypoactive delirium can be easily missed as patients may appear more withdrawn.

# Differential Diagnosis

Delirium can mimic several other conditions and it's crucial to consider the following in differential diagnosis, each with its key signs and symptoms:

- Dementia: Characterized by gradual onset, stable consciousness level, and progressive decline in cognitive function.
- Psychosis: May present with hallucinations and delusions, but usually with preserved orientation and memory.
- Depression: May exhibit poor concentration and slow cognition, but typically with a stable consciousness level and often accompanied by pervasive feelings of sadness or guilt.
- Stroke: Abrupt onset with focal neurologic signs and specific deficits in speech, motor, or sensory function.
  
# Investigations

- 4AT and CAM are commonly used tools for delirium assessment.

Initial investigations should include a comprehensive physical examination and infection screen. Additional investigations should be guided by clinical suspicion based on the patient's history and physical examination. These may include:

- Bedside - bladder scan, review medications, ECG (arrhythmias, ischaemic changes that could cause hypoperfusion) urine MC&S - you should not perform urine dipstick if >65 as they are less sensitive in this age group.
- Bloods: FBC, urea and electrolyes, liver function tests, thyroid function tests, and blood cultures.
- Imaging:  chest X-ray, or ultrasound of the abdomen. Neuroimaging with CT or MRI head is reserved for those without a clear identifiable cause.


# Management

Management of delirium primarily focuses on treating the underlying cause. Non-pharmacological strategies should be the first line, which include:

- Providing an environment with good lighting
- Maintaining a regular sleep-wake cycle
- Regular orientation and reassurance
- Ensuring the patient's glasses and hearing aids are used if needed

For patients who are extremely agitated and potentially a danger to themselves or others, pharmacological interventions such as small doses of haloperidol or lorazepam. Olanzapine may also be considered however, these should be used with caution, especially in the elderly, due to the risk of side effects. 

# NICE Guidelines

For more information, see [NICE CKS on delirium](https://cks.nice.org.uk/topics/delirium/).
896
2442
Delirium
Topic
57
Geriatrics
15716
Delirium, characterised by fluctuations in consciousness and attention, can present with both hyperactive and hypoactive features and may be precipitated by various causes including infections and medications.
A 78 year old man has been admitted to the ICU following a diagnosis of severe urinary tract infection, resulting in urosepsis. He subsequently develops an AKI and is catheterised on the ward. The nurses are seriously concerned about fluctuations in his mood. Over the last few days, he has periods of being withdrawn, disorientated and apathetic and periods of agitation, hallucinations and delusions.

What is the most likely aetiology of the patient's symptoms?
a