Organic vs Psychiatric Causes of Disturbed Behaviour

Patients present to the ED for a variety of reasons; some may have a background of mental health issues.

For those who present acutely it is important to assess the patient’s physical state as well as their mental state.

For those having taken an overdose, TOXBASE and the British National Formulary (BNF) can be used to obtain information on the risk of physical harm and the medical management of the patient [13].

Patients presenting with symptoms suggestive of psychiatric conditions should be thoroughly assessed to ensure organic causes are excluded. This can often be done from the history and examination.

Organic conditions can present with symptoms suggestive of psychiatric disease. These symptoms, however, can be attributed to a physical cause rather than a psychiatric cause [14].

Signs and symptoms

Signs and symptoms of psychiatric conditions suggestive of an organic cause include [15]:

• History of substance misuse
• Over 35 years of age at first presentation
• Fluctuating behaviour
• Predominantly visual hallucinations
• Lethargy
• Abnormal vital signs
• Poor cognitive function

Organic causes

Organic causes that can lead to disturbed behaviour include:

• Traumatic causes – head injury: acute and long term
• Infective causes – HIV, encephalitis, syphilis, malaria, meningitis, cerebral toxoplasmosis
• Neurological – Parkinson’s disease, CVA, epilepsy, Huntingdon’s disease
• Cardiac – Mitral valve disease (anxiety)
• Autoimmune – Systemic lupus erythematosus (SLE)
• Neoplasia – Frontal lobe, temporal lobe, paraneoplastic problems, e.g. hypercalcaemia
• Blood/bone – Haemolytic anaemias, e.g. Ribothymidine 5′- triphosphate, thrombotic thrombocytopaenic purpura (TTP)
• Endocrine – Andrenocortical diseases, thyroid disease, pheochromocytomas
• Degenerative – Dementia, visual hallucinations in partially sighted
• Drugs – Alcohol, illicit drugs, steroids
• Idiopathic – Genetic disorders, e.g. Huntingdon’s disease, storage disorders, e.g. Wilson’s disease
• Obstetric/gynecological – Pre-eclampsia, post-partum