Differential diagnoses and management of common psychiatric conditions

Differential Diagnoses and Management of Common
Psychiatric Conditions

Psychotic Disorder

Differential Diagnosis

Psychotic Disorders;
Non-psychotic disorders with psychotic Acute psychotic episode – recent life stressor, first episode, fast recovery Bipolar Affective Disorder Schizophreniform disorder – good Delusional Disorder interepisode function/remission Organic/Delirium Schizoaffective disorder – significant Dementia – usual y prior Hx, more common in Lewy body. Drug-induced psychosis Medication-induced e.g. steroids, anticholinergics. Management
Rule out organic causes:

Comprehensive history and examination (esp. neuro). Assess suicidality + homicidality Urine Drug Screen FBC / UEC/ LFTs / TFTs / CMP / VDRL / HIV ECG / CXR / CT head if indicated by Hx/Ex Head MRI if first episode psychosis Must medical y stabilise patient then contain if agitated • Ensure adequate staff, check for weapons, keep close to door, de-escalate. Explain in non-confrontational manner that you want to relieve some of their stress. Olanzopine 15-20mg loading dose; 5-10mg q4hrs titrated to effect up to 30mg/24hrs. ± Diazepam 5-20mg PO q2-6hrs up to 120mg/24hrs. ACCUPHASE (zyclopenthixol 100mg) IMI / Midaz 2.5mg ± droperidol 5mg IMI q20min 5mg Droperidol + 5mg Midazolam IV in 2.5mg increments q10-20min/q5min up to 20mg AWS if indicated.
First-line Treatment

Atypical antipsychotic (lower risk EPSE, better tolerated, more risk metabolic Sx) Olanzapine 5mg nocte initial y, increasing to 10mg nocte. The daily dose may be increased by 2.5 to 5 mg increments over 4 to 6 weeks to 20 mg daily Add mood stabiliser, antidepressant or benzodiazepine as indicated. Treatment resistant  depot meds, clozapine, ECT. Consider antipsychotic SE as; • Antiadrenergic (orthostatic HypoTN) Anticholinergic (constipation, urinary retention, dry mouth) Antihistaminergic (sedation) Antiserotinergic (sexual dysfunction) o Acute dystonia (oculogyric, laryngeal spasm – Rx benztropine 2mg BD) o Akathisia (Rx benztropine 2mg BD) o NMS (fever, autonomic instability, tremor, mental status changes – Rx dantrolene + cessation of antipsychotic) o QT prolongation o Metabolic Sx (weight gain, dyslipidaemia) o Tardive dyskinesia (Rx benztropine 2mg BD) o Parkinsonism (Rx benztropine 2mg BD) Kai Brown (2009) Depression

Differential Diagnosis

Psychiatric Disorders
Other disorders w/ Depression; Dysthmia, chronic situational Neurological – AD, PD, MS, epilepsy, Adjustment disorder/Bereavement hypoactive delirium. Endocrine – Addison's, Cushing's, MDE w/ Melancholia Hyper/hyothyroidism, premenstrual Sx Metabolic/Haem – hypoglycaemia, Anxiety Disorder anaemia, hypercalcemia, low B12 Schizophrenia (-ve Sx) Drug – AntiHTN, steroids, antihistamines, chemoTx, hormones, ETOH etc. Dementia/Psudodementia Other – SLE, sleep apnoea, malignancy, Non-pathological saddness Management

Risk assessment to self / to others  may have to admit under MHA schedule 2.
Rule out organic causes, melancholia and bipolar.
There are no specific tests for depression. Investigations focus on the exclusion of treatable
causes (see above), or other secondary problems (e.g. loss of appetite, alcohol misuse).

o FBC, ESR, B12/folate, U&Es, LFTs, TFTs, glucose, Ca2+ Focused investigations (if indicated by history or physical signs) Have to engage patient in therapeutic relationship via normalisation & psychoeducation. Strategies for high relapse and recurrence. Regular fol ow up. Adjustment disorder / non-melancholic / mild depression Good response to counsel ing and CBT. May augment with SSRI's if needed. Moderate to Severe Depression • First-line SSRI + psychotherapy o e.g. Sertraline 25mg OD for 7/7 then 50mg OD. o May cause GI upset, CNS symptoms, sexual dysfunction. Usual y settles after first 2/52. Therapeutic after 4-6/52. SSRIs inhibit P450. May go multimodal in resistant depression or if there are SE. o e.g. Venlafaxine (stronger), Mirtazapine (sedating), TCA (sedating), MAOI/RIMA, nefazodone (less sexual SE). May augment using a mood stabiliser e.g. Valproate, Lithium, Olanzapine . May need antipsychotic if displaying psychotic features (esp. delusions of guilt, AH). ECT very effective. Kai Brown (2009) Acute Mania

Differential Diagnoses

Psychiatric Disorders
Other disorders w/ Mania; Bipolar Disorder Neurological – TLE, MS, neoplasm, Cyclothymic disorder neurosyphilis, trauma. Psychotic Disorder Endocrine – Hyperthyroidism Drug – Steroids, stimulants, antidepressants, ECT, dopamine agonists, sympathomimetics.

Risk assessment to self / to others  may have to admit under MHA schedule 2.
Rule out organic causes.

FBC / UEC / CMP / TFTs / Urine drug analysis / Head MRI Acute Management – sedation with antipsychotic • o 100mg BD on the first day, increasing rapidly to 200 mg BD. Response is frequently not seen until higher doses are achieved of up to 400 mg twice daily. Extra sedation achieved with 50mg doses. Lithium – assess renal and thyroid function prior to Rx. o 750 to 1000 mg OD, in 2 or 3 divided doses. Serum concentration should be determined after 5 to 7 days of steady dose treatment. The daily dose may be increased in increments of 250 to 500 mg depending on serum concentration. o Aim for higher serum conc. than in maintenance (0.8 to 1.2 mmol/L). o The daily dose required to achieve therapeutic concentration may range from 1000 to 2500 mg. o Serum lithium concentration should be estimated 12 hours after the last dose. o Use lower doses in elderly (narrow therapeutic range).  At therapeutic concentrations lithium can produce fine tremor, muscular weakness and (rarely) EPSE. Cognitive difficulties, including memory problems, appear to be more common than previously recognised.  Acute ingestions of less than 25 g are unlikely to cause major effects unless patients have renal failure. / dehydration / diuretics / ACEi / A2RB.  The main clinical features of toxicity are: GIT effects: nausea, vomiting and diarrhoea CNS effects: tremor, hyperreflexia, ataxia and dysarthria in mild to moderate toxicity; confusion, coma, seizures in severe toxicity. CV effects: QT prolongation and hypotension in severe cases.  Most patients with acute poisoning require no specific treatment except serial measurement of lithium concentrations to confirm elimination. Sodium Valproate o 200 to 400 mg BD. The dose should be increased every 2 to 3 days by increments of 200 to 500 mg per day and plasma concentration determined after 3 days of steady dose treatment. o Titrate to clinical effect. Most patients require a regular daily dose of 1000 to 2000 mg, though some may need 3000 mg or higher. o Monitor for raised LFTs, thrombocytopenia, Rx OD w/ hydration and activated o Tremor, hair loss, sedation and weight gain are the commonest adverse effects. Kai Brown (2009) Bipolar Affective Disorder

Differential Diagnoses

Psychiatric Disorders
Other disorders w/ Mania; Bipolar Disorder Neurological – TLE, MS, neoplasm, neurosyphilis, trauma. Cyclothymic disorder Endocrine – Hyperthyroidism Drug – Steroids, stimulants, Psychotic Disorder antidepressants, ECT, dopamine agonists, sympathomimetics.

Risk assessment to self / to others  may have to admit under MHA schedule 2.
Rule out organic causes.

FBC / UEC / CMP / TFTs / Urine drug analysis / Head MRI Acute Management As above for either manic episode (≥1 week) or depressive episode (≥2 weeks). Would include the addition of a mood stabiliser. • Valproate less toxic, Olanzapine good for mania, Lamotrigine best for prevention of depression, Lithium very effective overal but with risk toxicity. Long Term / Maintenance Mx – BIOPSYCHOSOCIAL model Biological • Quetiapine 20mg nocte Lithium 750 – 1000mg then titrate to 0.6 – 0.8mmol/L Valproate - As above Lamotrigine 200mg nocte (start low, go slow) o Lamotrigine can cause skin reactions of varying severity:  a mild maculopapular rash;  a more serious rash associated with fever,  arthralgias and eosinophilia;  severe and potential y fatal skin reactions including Stevens-Johnson syndrome and toxic epidermal necrolysis. o The risk of skin reactions is increased by concomitant sodium valproate therapy and/or rapid dose escalation. Psychological: • supportive and psychodynamic psychotherapy, cognitive or behavioural therapy Must identify prodromal state/triggers to prevent ful relapse. o E.g. bright clothes, over-confident, intrusive, irritable, change in character… vocational rehabilitation, leave of absence from school/work, drug and EtOH avoidance, Office of Protective Commissioner, sleep hygiene, social skil s training, education for family members Kai Brown (2009) Drug/ETOH Withdrawal


75% Psychiatric Admissions test positive to il icit substances 60% Presentations to outpatient D&A services have concurrent psychiatric diagnosis Comprehensive and detailed D&A Hx – must gain trust. Must determine both functional (5 L's) and heath consequences from abuse. s this an abuse (no withdrawal, functional impairment) or a dependence (with
withdrawal, drinking most days, drinking early) – both continue to use despite adverse

Acute Management of ETOH abuser….

100mg Thiamine IMI OD for 1/7 + 100mg Thiamine PO TDS for 7/7 (before food to avoid refeeding syndrome / precipitation of Wernicke's !!!!) Do BSL – give glucose if necessary + ABG to look for acidosis. Do BAL (can only give diazepam if <0.15 due to resp. depression) Set up AWS (patients with liver disease wil need a lower dose – can use lorazepam which has a shorter half life and less first pass metabolism if needed) o Diazepam 10-20mg q2hrs until asymmp. up to 100mg/24hrs. o Diazepam 2-5mg IV up to 20mg/hr o Lorazepam 1-2mg PO TDS-QID. Investigations • BSL, FBC, LFT, Thyroid, UEC, B12/folate, Coags, o ALT+GGT > AST in ETOH, AST > ALT in hepatitis Urine Drug Screen ECG ± CXR, head CT if indicated. Screen for Health Consequences of ETOH Abuse – start head to toe • Cognitive deficit (Wernicke-Korsakoff Sx), opthalmoplegia, ataxia, fal s, subdural, DT (delirium, autonomic hyperactivity, VH/AH, fluctuating LOC). Ca tongue, poor dentition, parotid enlargement Oesoph – varices, oesophagitis, throat Ca, GORD GIT – gastritis, malabsorption, diarrhoea Cardioresp – cardiomegaly, aspiration pneumonia Liver – fatty liver, steatohepatitis, cirrhosis, sceral icterus, palmar erythema, telangiectases, gynecomastia, testicular atrophy, easy bruising (decr. Clotting factors) Haem – megaloblastic anaemia (or mixed), poor immune function Metab – malnutrition, sensitive to hypoglcaemia. Peripheral Neuropathy
Long-term management

Stabilise any heath consequences.
Refer to D&A services ± counsel ing re: concomitant psych; high relapse prevention.

Harm Minimisation (NSPs, spontaneous remission) Mutual help groups: AA, NA Counseling: group or individual CBT – addresses motivation Detoxification: inpatient or outpatient Rehabilitation: 3 weeks to 2 years Pharmacotherapy – withdrawal or abstinence support; replacement – Alcohol: Campral, Naltrexone, diazepam – Heroin: Naltrexone, Methadone, Buprenorphine Kai Brown (2009) Delirium

Immediate management
Must do risk assessment (special attention to behaviours).

Get history from nursing staff re: VH/AH, behaviour, memory first. R/V notes + med chart. Check Obs, ensure stable, give oxygen, get IV access. Haloperidol 0.5mg IMI if agitated. May have to move to quiet, safe place. Do ful Hx/Ex/MSE/serial MMSE. Can be HYPERactive or HYPOsctive Investigations: - Medication review (started, ceased, changed dose) FBC / UEC / LFT / TFT / CMP / VitB12 & Folate / BAL / ESR+CRP Septic Screen / HIV / VRDL ECG / CXR / non-contrast Head CT/MRI (? Stroke/lesion) / EEG Minimise polypharmacy + Withdraw suspect drugs Ensure adequate hydration Correct metabolic disturbances Alcohol withdrawal scale Correct sleep-wake cycle Correct environment o Mid-level lighting; consistent staff if possible; familiar items around bed Correct sensory deficiencies o Glasses and Hearing aids May need 1:1 nursing care Physical restraint Constipation and catheters. Sedation can make symptoms worse. Sedation - Use smal est possible dose Can increase confusion and risk of fal s Use if risk to self/others; need investigations or treatment; if they are distressed by AH/VH/delusions. - Low dose neuroleptics haloperidol 2.5mg PO/IM – increase after 1-2hrs monitoring up to 10mg/24hrs.
Give 2mg Midazolam for sedation if safe airway. Monitor sedation, EPSE. Note benzos often WORSEN the symptoms of delirium. Ask, "is this person neuroleptic naïve or old?" if so, dose @ 0.5mg up to 4mg/24hrs. Use Benztropine 2mg PO for EPSE. Use respiridone 0.5-2mg OD if intolerant. - Avoid excess PRN + complications.
Intermediate management
R/V Ix next morning + nursing notes.
R/V patient to note fluctuation.
Contact family for col ateral + counsel ing/reassurance.
May need neuropsychiatric assessment for dementia.
Kai Brown (2009) Anxiety Disorders
Differential Diagnoses

Psychiatric Disorders
Other disorders w/ Mania; Acute Stress Disorder Neurological – CVD, MS, neoplasm, PD, HD, epilepsy, trauma. Endocrine – Hyperthyroidism, Panic Disorder ± agoraphobia phaeochromocytoma, Addison's, hypoglycaemia, hypocalcaemia Drug – Caffeine, stimulants, withdrawal, sympathomimetics. Cluster C personality disorder Cardiopulmonary – PE, COPD, AMI, Asthma, CCF, arrhythmia


Risk assessment to self / to others  may have to admit under MHA schedule 2.
Rule out organic causes.

FBC / BSL / UEC / CMP / TFTs / Urine drug analysis / Head MRI / EEG / cortisol levels / Urine catecholamines Acute Management Rarely requires admission. • Psychoedcation about prognosis + likely relapse, how to identify and deal with panic attacks is very common. SSRI's are 1st line anti-worry agent e.g. Sertraline 25mg OD for 7/7 then 50mg OD. o Other antidepressants can be used, esp. if mixed anxiety/depression. o Avoid benzodiazepines if possible – may be used for short term relief.
Cognitive Behavioural Therapy has a central role;
1. Cognition – cognitive restructuring aims to highlight, then change maladaptive cognitive
beliefs and processes E.g. overestimating probability and over-catastrophising 2. Control ing autonomic response – aims to minimise arousal and thought hoping. Relaxation, breathing techniques, mediation (dearousal by focusing) i. Good for panic disorder and PTSD 3. Graded Exposure – habitualises patient to stimuli Must occur in safe environment In hierarchical order or flooding Need repeated sessions, session must not end until anxiety has subsided at least a bit. i. Good for OCD, PTSD, panic disorder 4. Focused problem solving (good for GAD) Kai Brown (2009) Dementia

A. development of multiple cognitive deficits manifested by both

memory impairment (impaired ability to learn new information or to recal previously learned information) one or more of the fol owing cognitive disturbances – aphasia, apraxia, agnosia, disturbance in executive function
Differential Diagnoses
Psychiatric Disorders

Other disorders; MDE, esp. melancholic Neurological – Stroke, MS, neoplasm, PD, HD, epilepsy, trauma, delirium. Endocrine – as per delirium Drug – Caffeine, stimulants, ETOH withdrawal, sympathomimetics. Cardiopulmonary – PE, COPD, AMI, Asthma, CCF, arrhythmia
Must do risk assessment (special attention to behaviours).

Get history from nursing staff re: VH/AH, behaviour, memory first. R/V notes + med chart. Check Obs, ensure stable, give oxygen, get IV access. Haloperidol 0.5mg IMI if agitated. May have to move to quiet, safe place. Do ful Hx/Ex/MSE/serial MMSE. Psychological (depression) and Functional state (ADLs) Ex. MUST RULE OUT ORGANIC CAUSES
Investigations: - Medication review (started, ceased, changed dose) FBC / UEC / LFT / TFT / CMP / VitB12 & Folate / BAL / FOBT Septic Screen / HIV / VRDL ECG / CXR / non-contrast Head CT/MRI (? Stroke/lesion) / EEG
Management Principals of Dementia – BIOPSYCHOSOCIAL FRAMEWORK
1. EARLY - consulting with the patient and family
Explain it is a progressive but slow disease; meds can slow it down but not stop or reverse or cure it; new medications being developed al the time. Discuss financial (enduring attorney) and health/social/end of life (guardianship) issues. Explain can have a good QoL and remain independent until the late stages Explain 2x risk in 1st degree relatives (i.e. 10% at 65) Pharm – ACh esterase inhibitors (donepezil) Decreasing independence in ALDs – involve OT, social worker, physio, respite care, support groups More "PBSD" (behavioural and psychological problems of dementia) o Aggression, agitation, irritable, disinhibited, apathy, misidentification Sx. Rx respiridone 0.5-1mg or Quetiapine 25mg. o !st line depression – citalopram (short acting; P450 inhib.). Also decr. Agitation and VH. Often depression and apathy are mixed up. o Can help to maintain familiar surrounds as per the preserved long term memory, read old books again, watch old movies etc. i.e. orientation. Be aware of increased carer stress, behavioural problems, other comorbidities, decr. ADLs, often need 24hr care in a facility. Kai Brown (2009) DSM-IV Criteria for common psychiatric conditions

Diagnostic criteria for Schizophrenia

A. Characteristic symptoms: Two (or more) of the fol owing, each present for a significant
portion of time during a 1-month period (or less if successful y treated): 1. delusions 2. hal ucinations 3. disorganized speech (e.g., frequent derailment or incoherence) 4. grossly disorganized or catatonic behavior 5. negative symptoms, i.e., affective flattening, alogia, or avolition Note: Only one Criterion A symptom is required if delusions are bizarre or hal ucinations consist of a voice keeping up a running commentary on the person's behavior or thoughts, or two or more voices conversing with each other. B. Social/occupational dysfunction: C. Duration: Continuous signs of the disturbance persist for at least 6 months. This 6-month period must include at least 1 month of symptoms D. Schizoaffective and Mood Disorder exclusion
E. Substance/general medical condition exclusion
F. Relationship to a Pervasive Developmental Disorder:
Brief psychotic disorder = 1 day to 1 month
Criteria for Manic Episode

A. Distinct period of abnormal y and persistently elevated, expansive, or irritable mood,
lasting at least 1 week (or any duration if hospitalization is necessary). B. During the period of mood disturbance, three (or more) of the fol owing symptoms have persisted (four if the mood is only irritable) and have been present to a significant degree: 1. inflated self-esteem or grandiosity 2. decreased need for sleep (e.g., feels rested after only 3 hours of sleep) 3. more talkative than usual or pressure to keep talking 4. flight of ideas or subjective experience that thoughts are racing 5. distractibility (i.e., attention too easily drawn to unimportant or irrelevant external 6. increase in goal-directed activity (either social y, at work or school, or sexual y) or psychomotor agitation 7. excessive involvement in pleasurable activities that have a high potential for painful consequences (e.g., engaging in unrestrained buying sprees, sexual indiscretions, or foolish business investments) C. The symptoms do not meet criteria for a Mixed Episode (see Criteria for Mixed Episode). D. The mood disturbance is sufficiently severe to cause marked impairment in occupational functioning or in usual social activities or relationships with others, or to necessitate hospitalization to prevent harm to self or others, or there are psychotic features. E. The symptoms are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication, or other treatment) or a general medical condition (e.g., hyperthyroidism).
Criteria for Major Depressive Episode

A. Five (or more) of the fol owing symptoms have been present during the same 2-week
period and represent a change from previous functioning; at least one of the symptoms is either (1) depressed mood or (2) loss of interest or pleasure. Note: Do not include symptoms that are clearly due to a general medical condition, or mood-incongruent delusions or hal ucinations. 1. depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g., feels sad or empty) or observation made by others (e.g., appears tearful). Note: In children and adolescents, can be irritable mood. Kai Brown (2009) 2. markedly diminished interest or pleasure in al , or almost al , activities most of the day, nearly every day (as indicated by either subjective account or observation made by others) 3. significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body weight in a month), or decrease or increase in appetite nearly every day. Note: In children, consider failure to make expected weight gains. 4. insomnia or hypersomnia nearly every day 5. psychomotor agitation or retardation nearly every day (observable by others, not merely subjective feelings of restlessness or being slowed down) 6. fatigue or loss of energy nearly every day 7. feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly every day (not merely self-reproach or guilt about being sick) 8. diminished ability to think or concentrate, or indecisiveness, nearly every day (either by subjective account or as observed by others) 9. recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific plan, or a suicide attempt or a specific plan for committing suicide. B. The symptoms do not meet criteria for a Mixed Episode (see Criteria for Mixed Episode). C. The symptoms cause clinical y significant distress or impairment in social, occupational, or other important areas of functioning. D. The symptoms are not due to the direct physiological effects of a substance (e.g., a drug of abuse, a medication) or a general medical condition (e.g., hypothyroidism). E. The symptoms are not better accounted for by Bereavement, i.e., after the loss of a loved one, the symptoms persist for longer than 2 months or are characterized by marked functional impairment, morbid preoccupation with worthlessness, suicidal ideation, psychotic symptoms, or psychomotor retardation.
Diagnostic criteria for Major Depressive Disorder, Single Episode

A. Presence of a single Major Depressive Episode (see Criteria for Major Depressive
B. The Major Depressive Episode is not better accounted for by Schizoaffective Disorder and is not superimposed on Schizophrenia, Schizophreniform Disorder, Delusional Disorder, or Psychotic Disorder Not Otherwise Specified. C. There has never been a Manic Episode (see Criteria for Manic Episode), a Mixed Episode (see Criteria for Mixed Episode), or a Hypomanic Episode (see Criteria for Hypomanic Episode). Note: This exclusion does not apply if al of the manic-like, mixed-like, or hypomanic-like episodes are substance or treatment induced or are due to the direct physiological effects of a general medical condition.
Criteria for Melancholic Features Specifier

With Melancholic Features (can be applied to the current or most recent Major Depressive
Episode in Major Depressive Disorder and to a Major Depressive Episode in Bipolar I or
Bipolar II Disorder only if it is the most recent type of mood episode)
Either of the fol owing, occurring during the most severe period of the current episode:
1. loss of pleasure in al , or almost al , activities
2. lack of reactivity to usual y pleasurable stimuli (does not feel much better, even
temporarily, when something good happens) Three (or more) of the fol owing: 1. distinct quality of depressed mood (i.e., the depressed mood is experienced as distinctly different from the kind of feeling experienced after the death of a loved one) 2. depression regularly worse in the morning 3. early morning awakening (at least 2 hours before usual time of awakening) 4. marked psychomotor retardation or agitation 5. significant anorexia or weight loss 6. excessive or inappropriate guilt Kai Brown (2009)

Source: http://medsoc.org.au/mednotes/Psych_common_conditions.pdf


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