Psychosis Flashcards
What are common iatrogenic causes of delirium?
- Benzodiazepines
- Anticholinergics
- Antihistamines
- Narcotics
What are common medical causes of delirium?
- Electrolyte imbalances
- Hypo/hyperglycemia
- Pneumonia
- UTI
- Hypercapnia
- Hypoxia
What is the most sensitive method of detecting delirium?
EEG => demonstrating generalized slowing
What is the differential diagnosis (psychiatric) for psychosis?
- schizophrenia/schizophreniform/schizoaffective
- delusional disorder
- bipolar disorder, manic/mixed episode
- brief psychotic disorder
- severe depression
- substance induced
- delirium (dementia)
What is the difference between an illusion and hallucination?
- illusion => misinterpretation of an existing sensory stimulus (mistaking a shadow for a cat)
- hallucination => sensory perception without an actual external stimulus
What are medication/substance induced causes of psychosis?
- Corticosteroids
- Antiparkinsonian agents
- Anticonvulsants
- Antihistamines
- Anticholinergics
- Some antihypertensives: beta blockers, digitalis, methylphenidate, flouroquinolones
- Alcohol
- Hallucinogens (LSD, Ecstasy)
- Marijuana
- Benzodiazepines
- Barbituates
- PCP
What is the appropriate work up for psychosis without prior psychiatric history?
- Rapid plasma reagin (RPR- syphillis)
- TSH
- Brain imaging
What are the 5 As of schizophrenia?
Anhedonia Affect (flat) Alogia (poverty of speech) Avolition/Apathy Attention (poor)
Describe the genetic predisposition of schizophrenia.
- 50% concordance rate among a monozygotic twins
- 40% risk of inheritance if both parents have schizophrenia
- 12% risk if one first degree relative is affected
What is akathisia?
Akathisia is an unpleasant subjective sense of restlessness often manifested by the inability to sit still.
What is the lifetime prevalence of schizophrenia?
1%
Describe the pathophysiology of schizophrenia.
- inadequate dopaminergic activity in the prefrontal cortex responsible for negative symptoms
- excessive dopaminergic activity in the mesolimbic system responsible for positive symptoms
Apart from dopamine abnormalities, what other neurotransmitter abnormalities are implicated in schizophrenia?
- elevated serotonin
- elevated norepinephrine
- decreased GABA (decreased expression of the enzyme necessary to create GABA in the hippos campus)
- decreased levels of glutamate receptors (fewer NMDA receptors- similar to ketamine, an NMDA antagonist)
What might a CT of a patient with schizophrenia demonstrate?
- Enlarged ventricles
- Diffuse cortical atrophy
What substance abuse disorders often have the complaint of tactile hallucinations known as formication?
Heavy use of cocaine and amphetamines can be a cause of formication
