Disorders due to a General Medical Condition

Disorders due to a General Medical Condition

·        Psychiatric symptoms occur in a wide range of medical conditions

·        Neurological: 

o   Degenerative: Parkinson‟s, Huntington‟s, Wilson‟s ® depression, dementia, psychosis

o   Epilepsy: 30 – 50 % have psychiatric illness at some stage, can be due to medication

o  Brain tumours: especially frontal lobe or limbic system

o  Head injury

o  Demyelinating disorders: eg MS

·        Infectious: 

o  Herpes simplex encephalitis ® changed personality, psychosis

o  Rabies, syphilis, CJD, Kuru (in PNG)

o  HIV

·        Autoimmune: Systemic lupus erythmatosus: eventually 50% have psych symptoms

·        Endocrine: 

o  Hyperthyroid ® confusion, anxiety, agitated depression, manic, delusions, with weakness and muscle loss 

o  Hypothyroid ® if severe then hypomania, depression, hallucinations 

o  Hypercalcaemia (due to PTH disorder) ® delirium, changed personality, apathy, ¯cognitive function 

o  Hypocalcaemia (due to PTH disorder) ® delirium, changed personality, eventually tetany

o  Hypoadrenocorticism (Addison‟s) ® apathy, depression

o  Hyperadrenocorticism (Cushing‟s) ® agitated depression

o  Total pituitary failure ® hypothyroid and hypoadrenocorticism

·        Metabolic: 

o  Hepatic encephalopathy ® ¯memory, ¯LOC, changed personality

o  Uraemia encephalopathy: renal failure ® ¯memory, ¯orientation, ¯LOC

o  Hypoglycaemia: agitation/restlessness 

o  Ketoacidosis ® easy fatigue 

o  Acute intermittent porphyria ® ­porphyrins (components of haemoglobin synthesis): acute colicky abdominal pain, motor polyneuropathy, psychosis, anxiety, insomnia, lability of mood, depression. Barbiturates absolutely contraindicated. 0.2 – 0.5 % psych patients have undiagnosed porphyria 

·        Nutritional:

o  Niacin deficiency

o  Thiamine deficiency 

o  B12 deficiency ® neuro degeneration ® depression, irritability, moodiness

·        Toxins:

o  Mercury: depression, irritability, psychosis, tremour, weakness

o  Lots of others

·        Cancers Eg carcinoma of the pancreas

·        Medication:

o  Mood disturbances from: stimulants, steroids, L-dopa, etc 

o  A previous condition (eg major depressive disorder) can be triggered by medication with the capacity to cause depressive symptoms