Diff Diagnosis List #2

Diff Diagnosis List #2

VI - Diff dx of Dementia
VII - Diff dx of ataxia and ophthalmoplegia
VIII - Diff dx of altered mental status, fever, headache
 IX - Diff dx of gradual onset hemiparesis
X - Workup of Multiple Sclerosis
XI - Brain death criteria
 
Diff dx of dementia

Vascular – Strokes, diffuse ischemic injuries
Infectious – Syphilis, chronic meningitis (TB, fungal), HIV dementia, PML, CJD
Trauma – SDH, dementia pugilistica
Autoimmune – CNS vasculitis, MS
Metabolic/toxic – hypothyroidism, vitamin B12, hepatic, renal failure, hypercalcemia, Korsakoff syndrome, heavy metal intoxication (lead, arsenic, bismuth), prolonged hypoglycemia, hypoxia
Idiopathic – Alzheimer’s disease, Parkinson’s dementia, dementia with Lewy bodies, PSP, MSA, ALS-Parkinson dementia of Guam, frontotemporal dementias, Wilson’s disease, primary progressive aphasia
Neoplastic – brain tumor, CNS lymphoma, paraneoplastic limbic encephalitis, postradiation effects
Miscellaneous – psuedodementia secondary to depression, complex partial seizures, NPH

Workup
Labs – CBC, BMP, LFT, vitamin B12, VDRL, TSH, ESR, HIV (if applicable), toxicology screen (if applicable)
Imaging – MRI brain
Lumbar puncture – therapeutic large volume tap, 14-3-3 protein assay (if applicable)
Depression screening
Head trauma screening

Diff dx of subacute presentation of ataxia and ophthalmoplegia

Miller Fisher variant of GBS
Wernicke’s encephalopathy
Toxins – botulism (ileus + fixed pupils), marine toxins, tick paralysis
Posterior circulation stroke
Myasthenia gravis
Hypothyroidism (peripheral neuropathy + cerebellar degeneration)
Paraneoplastic cerebellar degeneration

Workup:
Labs – CBC, BMP, LFT, TSH, Lyme titer (if applicable)
Imaging – MRI/MRA
Tx – thiamine + glucose
Lumbar puncture
EMG (if Miller Fisher, myasthenia gravis suspected)






Diff dx of altered mental status, fever, meningismus, headache

Vascular – SAH, ICH (BG, thalamus, cerebellar if HTN), SDH, epidural hematoma, bilateral thalamic CVA
Infectious – bacterial meningitis, tuberculous meningitis, viral encephalitis
Metabolic-toxic – HTN encephalopathy (if HTN present), DKA induced coma, hepatic, renal encephalopathy, hypothyroid (asterixis +)
Tumor – hemorrhage into tumor
Autoimmune – CNS vasculitis

Workup:
Labs: CBC, BMP, LFT, TSH, ESR
Imaging: CT or MRI brain
Lumbar puncture

Diff dx of gradual onset hemiparesis

Neoplastic – 1 neoplasm including astrocytoma, oligodendroglioma, 1 CNS lymphoma), metastasis
Infectious – Abscess (bacterial, parasitic such as echinococcus, toxoplasmosis, fungal such as aspergilloma, mucoymycosis)
Vascular – CVA, ICH, complicated migraine, hemorrhage from AVM or aneurysm
Traumatic – SDH, epidural hematoma, contusion
Autoimmune – CNS vasculitis, MS
Metabolic – Hypoglycemia
Psychiatric – Conversion disorder

Workup:
Labs: CBC, BMP, LFT, ESR
Imaging: CT or MRI brain with contrast
Lumbar puncture

Immunocompromised:
Includes HIV, CD4 titers, CXR, blood cultures

Common organisms in brain abscesses:

1. Bacterial – strep, staph aureus, pseudomonas, enterobacteria, anaerobes
2. Immunocompromised – Cryptococcus, toxoplasmosis

Workup for MS

Basic Labs – CBC, BMP, LFT, TSH
MS masqueraders – ESR, ANA, ACE, CXR, vitamin B12, VDRL, Lyme titer, if indicated HIV, HTLV-1
Imaging – MRI brain with contrast, if MRI brain suspicious or exam demonstrates myelopathy, MRI C, T-spine with contrast
Lumbar puncture – IgG synthesis index, oligoclonal bands
Evoked potentials – VEP (1st choice, esp with optic neuritis presentation), BAER, SSEP

Brain death criteria

Prerequisites to determine brain death
Cause known and irreversible
No confounding medical condition
NL metabolic (electrolytes, acid base status, endocrine)
No drugs or poison
T > 32 C

Exam
Coma
No motor response
Corneal reflexes absent
Caloric testing negative aftger 1 min after irrigation
Gag reflex absent
No response to suction
No sucking/rooting reflex
No respiratory drive on apnea test

Apnea test
T > 36.5, BP > 90, + fluid balance
Preoxygenate with 100% O2 for 10 mins
Start pulse ox/D/C ventilator
100% O2 6L via cannula
After 8 mins obtain ABG
If desaturation or hypotension occurs, draw ABG
+ if no respiratory drive with PCO2 > 60 mm Hg or > 20 mm Hg above baseline

Confirmatory tests
Angiogram – no filling
EEG – 8 electrodes, impedance < 10 KU, 2 uV sensitivity, 10 cm between electrodes, 30 minute recording, NONREACTIVE rhythm
TCD – lack of diastolic flow
SPECT: hollow skull 30, 60 mins, 2 hrs after injection
SSEP: absent responses

Diff Diagnosis List

Diff Diagnosis List Part I

I - Differential Diagnosis of Stupor
II - Cerebral Vasculitis
III - Horner's Syndrome Review
IV - Subacute etiologies of Headache
V - Review of Nystagmus

Differential Diagnosis of Stupor

Vascular	CVA (brainstem, thalamic, large hemispheric) ICH SAH Epidural/subdural hematoma
Metabolic	Thyroid disturbance Adrenal insufficiency DKA, hyper, hypoglycemia Hepatic Renal Medication induced Toxin induced Wernicke’s encephalopathy
Infectious	Meningitis Encephalitis Brain abscess Sepsis
Neoplastic	1 brain tumor, metastasis Limbic encephalitis
Inflammatory	ADEM CNS vasculitis
Hypertensive encephalopathy
Seizures	Non convulsive status epilepticus Post icital
Hydrocephalus
Psychogenic coma

Workup

Labs – CBC, BMP, LFT, TSH, urine tox, ammonia, ABG, EKG, if infection suspected – CXR, U/A, blood, urine cultures
Tx – 100 mg IV thiamine then glucose
Imaging – CT or MRI brain, if no mass lesion or focal neuro deficit, LP, EEG











Causes of cerebral vasculitis

Primary angiitis of the CNS
Infectious – HIV, VZV
Meningitis – fungal, viral, treponemal, parasitic
Drug induced – amphetamines, cocaine
Lymphoma
GCA – high ESR, older age, EXTRADURAL

Systemic Vasculitis
Behcet’s – genital/oral ulcers, ocular signs
PAN – fever, arthralgias, myalgias, mononeuropathies
Churg Strauss – asthma, eosinophilia, neuropathy
Wegner’s - +ANCA, neuropathy
SLE – fever, rash, pleuritis, encephalopathy

Vasculitis workup:
Labs: ESR, CRP, ANA, CBC c diff, BMP
Imaging: CXR, MRI brain, MRA, CTA or angiogram of head and neck

Review of Horner’s syndrome

Horner’s syndrome – ptosis, anhidrosis, miosis

1 order sympathetic fibers: hypothalamus → brainstem → descend to interomediolateral cell column of spinal cord at C8-T2
2 order sympathetic fibers: exit spinal cord at T1 → ascend cervical sympathetic chain → synapse at superior cervical ganglion at carotid artery bifurication
3 order/postganglionic sympathetic fibers: travel along ICA → 1) sudomotor fibers travel along EXTERNAL carotid artery 2) pupillomotor fibers enter cavernous sinus → superior orbital fissure via long cillary nerve → iris dilator and Muller muscle

Agents to localize Horner syndrome
4% cocaine – inhibits NE reuptake, will lead to POOR papillary dilatation in sympathetic lesion at any order
1% hydroxyamphetamine – stimulates release of NE from presynaptic postganglionic nerve terminals, 1st, 2nd order fibers will result in papillary dilation, 3rd order will NOT dilate









Basic diff dx for subacute onset of severe HA

Vascular – ICH, SAH, CVT
Infectious – meningitis, encephalitis, brain abscess
Neoplastic – 1 neoplasm or metastatic
Idiopathic intracranial hypertension
Vasculitis – CNS or systemic
Metabolic – thyroid, electrolyte, toxin
Hydrocephalus

Labs – CBC, BMP, LFT, TSH, coags, ESR
Imaging – CT/MRI, CTV/MRV
Lumbar puncture







Characterization of Nystagmus

	Peripheral	Central
Vertigo	Intense	Mild
N/V	Intense	Less common
Duration	Short	Persitent
Fatigability	Yes	None with multiple trials
Direction	Fixed, horizontal or diagonal, rotatory or torsional	Multidirectional, can include vertical
Latency	Several seconds	None

Horizontal nystagmus if caused by labyrinth or vestibular nerve – the fast phase of nystagmus is opposite the affected side ie fast phase to L signals R vestibular dysfunction

Visual Hallucinations Review
Published and edited by Terrence Li M.D.
2010

Types of hallucinations –

Visual Hallucinations

First, differentiate between simple or complex hallucinations:
1)    Simple – “elemental or non formed”
a.    Lights, colors, lines, shapes or geometric shapes
b.    Light simple hallucinations can be delinated further into lights without structure (phosphenes) OR lights with structure (photopsias)
2)    Complex – “formed”
a.    Images of people, animals, objects or lifelike scene

Auditory Hallucinations  - one or more talking voices
Usually associated with psychotic disorders such as schizophrenia or mania, but can be caused by lesions in the brainstem, tumors, encephalitis or abscesses

Tactile hallucinations – sensation of tactile sensory input simulating various sensations of pressure to the skin or other organs “feels bugs crawling on them”
Usually always associated with exogenous substance abuse.

History

Description
Monocular vs binocular
Involved area of visual field
Motion – motion within the hallucination or movement of hallucination across field of vision
Triggers (dark room, anxiety, bright light)
Duration
Frequency
Insight?

Differential Diagnosis

Retinal pathology
Charles Bonnet hallucinations
Migraine with aura
Seizures – occipital, occipitotemporal, posterior temporal
Dementia with Lewy bodies, Parkinson disease
EtOH withdrawal
Peduncular hallucinosis
Narcolepsy
Psychiatric illness
Metabolic encephalopathy
Stroke
Others

Retinal Pathology

Etiologies include traction, irritation, injury or disease of retina, posterior vitreous detachment. Hallucinations are SIMPLE (streaks of light, sparks, flashes), lasting seconds, variable frequency, insight retained., invariably monocular except in cancer associated retinopathy which it may be binocular.

Migraine with aura – 90% auras in migraine are visual. Hallucinations are SIMPLE, typically linear and geometric (zig zag lines, scintillating scotoma, spots, shooting stars, fortification spectra), lasting 4-60 minutes, variable frequency, insight retained, binocular and usually start in the central of the visual field with growth and spread of the aura.
Always have associated symptoms such as nausea, vomiting, photophobia, phonophobia, and they always follow the aura.
There is a special entity called acephalgic migraine in which there is a visual area as described above and there is no associated headache.

Seizures

Depending on the focus of the seizure, the hallucinations can be SIMPLE or COMPLEX:
1)    Occipital, occipitotemporal, occipitoparietal regions of cortex – SIMPLE hallucinations
a.    Brightly colored circles or spherical patterns
b.    Intrinsic motion of hallucination or move across the visual field is a hallmark!
2)    Occipitotemporal or posterior temporal regions of cortex – COMPLEX hallucinations

Epileptic visual phenomenon last for seconds, variable frequency, insight is usually retained, binocular usually occurring in one hemifield.

There are associated symptoms including déjà vu, jamais vu (temporal), somatosensory (parietal), forced head and eye deviation (frontal), motor activity (frontal and/or secondary generalization). There can be a posticital headache afterwards, making the distinction between migraine with aura and seizures difficult at times.

Dementia with Lewy bodies, Parkinson’s disease

Hallucinations are complex, binocular, occur throughout the visual field. Some examples are people, animals to abstract such as shapes and colors. These episodes last seconds to minutes, frequency usually is at least weekly. Insight may or may not be retained depending on the level of dementia/cognitive impairment. These images may spark feelings from indifference to fear (as in Phillip’s patient).
The difference is visual hallucinations are an early hallmark for DLB occurring in 2/3 of patients in the disease course. Parkinson’s disease hallucinations develop later in the disease course and can be exacerbated by dopamine agonists or carbidopa/levodopa.

Alcohol and drug use –
Alcohol and BDZ withdrawal – complex hallucinations without insight with VIVID imagery causing agitation, tremulousness and autonomic hyperactivity.
Medication induced or recreational drug use – complex, bilateral and full field with associated confusion and/or delirium. + tactile and auditory hallucinations.
Digoxin and sidenafil – there is RETINAL toxicity, simple hallucinations are produced such as “TV static”, tint of yellow or green in the visual field, dots of light, black spots. Long term supratherapeutic digoxin levels known to cause permanent retinal injury. ?? long term effect with sidenafil.

Non-psychotropic – digoxin, glucocorticoids, amantadine, H2 blockers, BB, sildenafil
Psychotropic – L-dopa, dopamine agonists, TCA, benztropine, BDZ, narcotics
Drugs of abuse – EtOH, LSD, PCP, cocaine, narcotics, ecstasy, amphetamine

Peduncular hallucinosis

Rare manifestation of stroke/neoplasm affecting the midbrain in particular the medial midbrain region affecting the reticular formation, red nucleus, raphe nucleus and oculomotor nucleus.  Pontine and thalamic lesions have been described with this phenomenon.
Hallucinations are complex, binocular, vivid and colorful imagery, +/- auditory and tactile content, and insight is variably retained. Duration variable from a few minutes to a few hours, frequency varies from 1-15 times a day. Predilection to occur in the evening. Usually self limited, resolving within a few weeks to months.
Invariably associated with other cranial nerve and consciousness symptoms: sleep wake cycle disturbances (daytime somnolence + night time insomnia), vertical gaze palsies, hemiparesis, ataxia, poor papillary light reaction, confusion.
Etiology has been postulated that the reticular activating system may be involved.

Narcolepsy

Hallucinations are complex, vivid, colored images, occurring immediately BEFORE falling asleep (hypnagogic) or just AFTER waking (hypnopompic). +/- auditory or tactile sensations, duration and frequency are variable. Insight is variably retained.
Associated symptoms include excessive daytime sleepiness, sleep paralysis and cataplexy.
Etiology is REM sleep into wakefulness, however, medications that disrupt sleep architecture (SSRI, anticholinergics) can do this as well.

Psychiatric illness

Hallucinations are visual, complex, associated with auditory hallucinations and usually occur in concert. Content is disturbing and antagonistic and patients lack insight. Duration and frequency is highly variable.
Associated symptoms include mania, anxiety, disordered thoughts, and delusions.

Metabolic Encephalopathy

Visual hallucinations occur in the context of waxing and waning confusion and agitation. Tactile and auditory hallucinations and delusions may occur too. The differential diagnosis of delirium is numerous: CNS infection,  systemic infection, hypoxia, medications, hepatic, renal encephalopathy, hypothyroidism, electrolyte abnormality.

Stroke

Beware of medial occipital + parahippocampal gyrus + hippocampus stroke, which causes delirium with visual hallucinations AND hemianopsia.

Others

Papilledema can cause photopsias or brief visual obscurations, lasting seconds, monocular, secondary to the elevated ICP induced edema of retinal ganglion cell axons, causing irritation of the retinal photoreceptor.

Optic neuritis can have visual hallucinations with eye movement in 30%.

Posterior reversible leukoencephalopathy syndrome can produce visual hallucinations with associated symptoms of visual field deficits, visual distortions, headache, altered mental status, seizures.

Diagnostic Approach

Complete physical and neurological examination,
Ophthalmological examination (esp if monocular and acute)
Review of medication list
Urine toxicology screen
CBC, BMP, LFT, TSH
ABG
MRI brain without contrast
EEG
Psychiatric consultation (if psych associated symptoms are appreciated)

Parkinson's Disease

Myasthenia Gravis Powerpoint Presentation

https://docs.google.com/presentation/pub?id=19uvKDv8bT8cR4V9IWmz9UHxQTiKsxx09vB9Uhf-bhXE&start=false&loop=false&delayms=3000