Multisystemic lens
The multisystemic lens is a component of the Diagnostic Lenses Framework ➚. This lens guides diagnostic formulation in patients presenting with psychiatric symptoms in the context of a suspected multisystemic disorder. It generates a differential diagnosis of conditions that:
involve the patient's specific combination of affected body systems; and
are recognised to cause psychiatric symptoms.
Psychosis is used as the principal psychiatric inclusion criterion because it is generally more indicative of underlying biological disease mechanisms than other psychiatric syndromes, such as depression or anxiety, which may also arise as psychological reactions to physical illness.
This lens is activated when involvement of at least two body systems is suspected (in addition to the CNS), based on abnormal findings on history, routine physical examination, or routine baseline investigations (blood tests and ECG).
To begin, select the two affected body systems from the chart below to explore the relevant differential diagnosis.
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