Flashcards in CN LANGE - Confusional States II Deck (101):
Wernicke encephalopathy - Pathologic features:
1. Neuronal loss.
3. Gliosis in periventricular gray matter.
+ Proliferation of small blood vessels and petechial hemorrhages may be seen.
Wernicke encephalopathy - The areas MC involved are:
1. The medial thalamus.
2. Mammillary bodies.
3. Periaqueductal gray mattter.
4. Cerebellar vermis.
5. Oculomotor, abducens, and vestibular nuclei.
Wernicke encephalopathy - The MC ocular abnormalities are:
2. VI nerve palsy.
3. Horizontal or combined horizontal-vertical gaze palsy.
4. GAIT ataxia primarily --> Ataxia of the arms is uncommon, as is dysarthria.
Wernicke encephalopathy - The mental status exam reveals:
Global confusion with a prominent disorder of immediate recall and recent memory.
Wernicke encephalopathy - The confusional state progresses to coma in a small or large percentage of patients?
Small percentage of patients.
Wernicke encephalopathy - Other neurologic features:
1. Associated neuropathy with absent ankle reflexes.
2. Pupillary abnormalities, including mild anisocoria, or a sluggish reaction to light, are occasionally seen
Wernicke encephalopathy - Anemia:
Wernicke encephalopathy - MRI:
May show atrophy of the mammillary bodies.
Wernicke encephalopathy - After treatment, ocular abnormalities usually begin to improve within ...?
Wernicke encephalopathy - After treatment ataxia and confusion begin to improve within ...?
Wernicke encephalopathy - After treatment ophthalmoplegia, vertical nystagmus, and acute confusion are entirely reversible, usually within ...?
Wernicke encephalopathy - After treatment horizontal nystagmus and ataxia resolve completely in approx. ...%.
B12 deficiency - Clinical findings - Presentation:
Usually with anemia or orthostatic lightheadedness but may also be neurologic:
1. Distal paresthesias.
2. Gait ataxia.
3. Bandlike sensation of tightness around the trunk or limbs.
4. Lhermitte sign (shock-like sensation along the spine precipitated by neck flexion) may be present.
B12 def. - Physical exam:
1. Low-grade fever.
3. Lemon-yellow discoloration of the skin.
4. Cutaneous hyperpigmentation.
B12 def. - Cerebral involvement:
4. Psychosis with hallucinations.
B12 def. - T1 MRI:
May show gadolinium enhancement of the posterior cord in B12 myelopathy.
B12 def. - T2 MRI:
Deep T2-signal abnormalities in B12 encephalopathy, which resolve with treatment.
B12 def. - The reversibility of neurologic complications:
Depends on their duration --> Abnormalities present for more than 1 year are less likely to resolve with treatment.
B12 def. - Encephalopathy may begin to clear within ...?
24h after first B12 dose - BUT full neurologic recovery, when it occurs, may take several MONTHS.
Organ system failure - Hepatic encephalopathy - The syndrome may be chronic and progressive or acute in onset - In the latter case, what are the precipitants?
1. GI hemorrhage.
2. Systemic infection.
4. Sedative drugs.
Hepatic encephalopathy - Cerebral symptoms are thought to result from ...?
1. Ammonia toxicity.
2. Cytotoxic edema.
3. Altered GABergic neurotransmission.
4. Inflammation among other factors.
Hepatic encephalopathy - Ocular disturbances:
1. Ocular reflexes are usually brisk.
3. Tonic DOWNWARD ocular deviation.
4. Disconjugate eye movements.
May be seen.
Hepatic encephalopathy - Other motor abnormalities include:
3. Paratonic rigidity.
5. Decorticate/decerebrate posturing.
6. Extensor plantar responses.
Uremia - Renal failure, particularly when acute or rapidly progressive, may produce ...?
Encephalopathy or coma with hyperventilation and prominent motor manifestations, including:
Uremia - The EEG is:
Diffusely slow and may show triphasic waves of paroxysmal spikes or sharp waver.
Dialysis itself can produce an encephalopathy:
Dialysis disequilibrium syndrome --> Thought to result from hypo-osmolarity.
--> This is MC with patient's first hemodialysis and can be prevented by correcting uremia more gradually or using briefer periods of dialysis at reduced rates of blood flow.
Pulmonary encephalopathy - Patients with lung disease or brainstem or neurologic disorders that affect respiratory function may develop encephalopathy related to ...?
Pulmonary encephalopathy - Symptoms include:
Pulm. encephalopathy - Exam shows:
4. Confusional state or coma.
Organ transplantation - Bone marrow or solid-organ transplantation may be associated with an acute confusional state related to:
1. Surgical complications.
2. Immunosuppressive drug treatment.
4. Opportunistic infection.
5. Reconstitution of the immune system.
6. Lymphoproliferative disorders.
7. Transplant rejection.
Organ transplantation - Surgical complications that may produce encephalopathy include:
4. Air embolism.
--> MC with liver + heart transplants.
Organ transplantation - Drugs - Fludarabine is associated with:
Increased risk for PML.
Organ transplantation - Drugs - Busulfan
Often produces seizures.
Organ transplantation - Drugs - Calcineurin inhibitors (cyclosporine and tacrolimus) produce encephalopathy that may be associated with:
3. Visual disturbances.
5. Sensory symptoms.
Organ transplantation - Drugs - Calcineurin inhibitors (cyclosporine and tacrolimus) - MRI may show:
Abnormalities in the occipital and posterior parietal white matter --> Posterior reversible encephalopathy syndrome.
Organ transplantation - Drugs - The monoclonal antibody OKT3 causes:
2. Aseptic meningitis.
Organ transplantation - Infections causing confusional states:
Most prominent after bone marrow transplantation but are also common after transplantation of other organs.
--> Comparatively RARE IN THE 1st MONTH.
Organ transplantation - Opportunistic infections are more common between 1 to 6 MONTHS after transplant and include:
1. Listeria meningitis or encephalitis.
2. Chronic meningitis from Cryptococcus or MTB.
3. Brain abscesses related to infection with Aspergillus, Nocardia, or Toxo.
Organ transplantation - Infections past 6 months:
Organ transplantation - IRIS (immune reconstitution inflammatory syndrome) related to transplantation is typically seen following ...?
Reduction of immunosuppressive therapy + institution of antibiotics for an opportunistic infection.
IRIS - Neurologic involvement:
2. Increased ICP.
3. CSF pleocytosis.
Posttransplant lymphoproliferative disorder is related to immunosuppression and may be associated with:
Primary CNS lymphoma.
Transplant rejection may also produce encephalopathy, especially in recipients of ... transplants.
Meningitis, encephalitis, and sepsis - Bacterial meningitis - Predisposing factors:
1. Systemic (especially respiratory) or parameningeal infection.
2. Head trauma.
3. Anatomic meningeal defects.
4. Prior neurosurgery.
7. Immunodeficiency states.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Neonates:
Ampicillin + Ceftriaxone or cefotaxime.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Child:
Ceftriaxone or cefotaxime + Vancomycin.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Adults
Ceftriaxone or cefotaxime + Vancomycin.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Adults >50y:
Ceftriaxone or cefotaxime + Vancomycin + Ampicillin.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Immunosuppression:
3. Gram(-) bacilli.
Ceftriaxone or cefotaxime + Vancomycin + Ampicillin.
Etiologic agents and empirical antibiotic treatment in bacterial meningitis - Head trauma, neurosurgery, or CSF shunt:
2. Gram(-) bacilli.
Vancomycin + Ceftazidime.
Bacterial meningitis - Bacteria typically gain access to the CNS by ...?
Colonizing mucous membranes of the nasopharynx --> Leading to local tissue invasion, bacteremia, and hematogenous seeding of the subarachnoid space.
Which bacterium is an exception in that it is ingested?
Bacterial meningitis - Pathology:
1. Leptomeningeal + perivascular infiltration with PMN leukocytes and an inflammatory exudate.
2. These tend to be most prominent over the convexities in S.pneumoniae and H.influenza.
3. N.meningitidis --> Base of the brain.
4. Brain edema, hydrocephalus, and cerebral infarction may occur ALTHOUGH bacterial invasion of the brain parenchyma is RARE.
Bacterial meningitis - Clinical findings - At presentation:
Most had symptoms for 1 to 7 days:
4. Neck stiffness.
--> The full syndrome is NOT usually present.
Bacterial meningitis - Physical exam:
1. Fever and signs of systemic or parameningeal infection, such as skin abscess or otitis.
2. Petechial rash in 50-60% of patients with N.meningitidis.
3. 80% --> signs of meningismus (ABSENT in the very young/old, immunosuppressed or confused).
Clinical findings in patients with bacterial meningitis:
87% --> Headache.
83% --> Neck stiffness.
77% --> Fever (>38).
69% --> Altered mental status.
33% --> Focal neurologic deficits.
26% --> Skin rash.
3% --> Papilledema.
--> 95% AT LEAST 2 of the first 4.
--> 44% neck stiffness + fever + altered mental status.
Laboratory findings in patients with bacterial meningitis:
92% --> CSF WBC>100.
82% --> CSF pressure >200mm water.
78% --> CSF WBC>1.000.
66% --> Positive blood culture.
34% --> Abnormal head CT scan.
Bacterial meningitis - The causative organism can be cultured from the BLOOD in approx. ... of cases.
Bacterial meningitis - The EEG:
Usually diffusely slow.
Bacterial meningitis - Gram-stained smears of CSF identify the causative organism in ...?
70-80% of cases.
Bacterial meningitis - CSF culture is positive in ...?
Approx. 80% of cases.
Bacterial meningitis - Contraindications for LP:
UNLESS the physical exam shows focal neurologic abnormalities or papilledema, suggesting a mass lesion, LP should be performed immediately.
Bacterial meningitis - LP can be repeated to assess the response to therapy:
1. CSF should be STERILE AFTER 24hours.
2. Decrease in pleocytosis + proportion of PMNs should occur within 3 DAYS.
Bacterial meningitis - Treatment - Dexamethasone?
Given immediately BEFORE the onset of antibiotic treatment and continued for 4 DAYS, may IMPROVE OUTCOME and decrease mortality in immunocompetent patients with confirmed bacterial meningitis.
Bacterial meningitis - Prognosis - Complications:
5. Residual neurologic deficits (including cognitive disturbances and cranial - especially VIII - nerve abnormalities).
Bacterial meningitis - Prognosis - Morbidity and mortality:
High --> Fatalities occur in approx. 20% of affected adults.
--> More often in low-income countries and with some pathogens (S.pneumoniae, gram(-) bacilli) compared to others (H.flu, Neisseria).
Bacterial meningitis - Factors that worsen prognosis:
1. Extremes of age.
2. Delay in diagnosis/treatment.
3. Complicating illness.
4. Stupor or coma.
6. Focal neurologic signs.
Tuberculous meningitis must be considered in patients who present with a confusional state, especially if there is a history of:
1. Pulm. TB.
3. Corticosteroid treatment.
4. HIV infection.
5. Other conditions associated with impaired immune responses.
Tuberculous meningitis - The main pathologic finding:
Basal meningeal exudate containing primarily MONONUCLEAR cells.
Tuberculous meningitis - Other pathologic features:
1. Tubercles may be seen on the meninges and surface of the brain.
2. Ventricles may be enlarged as a result of hydrocephalus.
3. Their surfaces may show ependymal exudate OR granular EPENDYMITIS.
4. Arteritis can result in cerebral infarction.
5. Basal inflammation and fibrosis can compress cranial nerves.
Tuberculous meningitis - Clinical findings:
Symptoms usually have been present for LESS than 4 weeks at the time of presentation and include:
3. Neck stiffness.
5. Lethargy or confusion.
--> Weight loss, visual impairment, diplopia, focal weakness, and seizures may also occur.
Tuberculous meningitis - Complications include:
3. Brain edema.
4. Visual loss.
5. Cranial nerve (especially VI) palsies.
6. Spinal subarachnoid block.
Tuberculous meningitis - Stroke usually affects:
1. Internal capsule.
2. Basal ganglia.
Tuberculous meningitis - Positive skin test for TB or evidence of active or healed tubercular infection on CXR:
ONLY 1/2 TO 2/3.
Tuberculous meningitis - The diagnosis is established by:
--> DEFINITIVE diagnosis is most often made by CULTURING M.tuberculosis from the CSF, a process that usually takes several weeks + requires large quantities of spinal fluid for maximum yield.
Tuberculous meningitis - Treatment:
INH --> 300mg.
Rifampin --> 600mg.
Pyrazinamide --> 1.600mg.
Ethambutol --> 1.200mg.
each given orally once daily FOR THE 2-MONTH INITIATION PHASE of therapy.
--> During the subsequent 7- to 12-month continuation phase, ONLY INH and rifampin are used at the same doses.
Tuberculous meningitis - Pyridoxine for INH-induced polyneuropathy?
Tuberculous meningitis - Prognosis:
EVEN with appropriate treatment, approx. 1/3 SUCCUMB.
Tuberculous meningitis - Adverse prognostic factors include:
4. Concomitant HIV infection.
5. Neurologic sequelae --> Cognitive disturbances, visual loss, motor deficits, and cranial nerve palsies.
Acute or subacute --> Usually occurs within 2 YEARS AFTER primary syphilitic infection.
--> MC in young adult males.
In approx. ... of patients with T.pallidum infection, treponemes gain access to the CNS, where they produce a meningitis that is usually asymptomatic:
Asymptomatic neurosyphilis is associated with CSF:
2. Elevated protein.
3. Positive serologic tests for syphilis.
Syphilitic meningitis - At presentation:
Headache, nausea, vomiting, stiff neck, mental disturbances, focal weakness, seizures, deafness, and visual impairment usually have been present for up to 2 MONTHS.
Syphilitic meningitis - Physical exam:
2. Confusion or delirium.
Syphilitic meningitis - The cranial nerves most frequently affected are (in order):
Syphilitic meningitis - Fever is typically ...?
Syphilitic meningitis treatment - The CSF should be examined every ...?
6 MONTHS until all findings are normal.
Lyme disease - Most cases occur during which season?
Lyme - Neurologic involvement may be delayed for up to ...?
Lyme - Neurologic involvement is characterized by:
1. Meningitis or meningoencephalitis.
2. Disorders of the CNs or peripheral nerves or nerve roots.
3. BILATERAL facial weakness from involvement of the VII is particularly COMMON.
Lyme meningitis - Produces:
1. Prominent headache.
4. Pain when moving the eyes.
Lyme meningitis - When encephalitis is present is usually ...?
MILD and characterized by insomnia, emotional lability, or impaired concentration and memory.
European Lyme disease differs clinically from that seen in the United States in that ...?
The infective organism is Borrelia garinii or Borrelia afzelii.
--> ERYTHEMA MIGRANS IS NOT A FEATURE.
--> Painful radiculopathy (Bannwarth syndrome) is common.
Lyme disease - Definitive diagnosis:
Usually made by serologic testing for B.burgdorferi --> Using ELISA for screening followed by western blot to confirm positive ELISA results.
Treatment of Lyme disease with neurologic involvement:
IV ceftriaxone (2g/d), cefotaxime (2g/3x daily), or penicillin (20-24x10^6 units/d) for 2-4 WEEKS.
Symptoms of acute Lyme disease typically resolve within 10 days in treated cases. Untreated or inadequately treated infections may lead to ...?
1. Recurrent oligoarthritis.
2. Memory, language, and other cognitive disturbances.
3. Focal weakness.
Untreated or inadequately treated Lyme infections - CT scan or MRI may show:
2. Lesions in white matter resembling those seen in MS.
3. Abnormalities suggesting cerebral infarction.
Causes of CHRONIC meningitis - Infectious:
1. Bacteria --> Partially treated, TB, syphilis, Lyme, leptospirosis, brucellosis, mycoplasma.
2. Viruses (HIV, EBV, HSV-2).
5. Parameningeal infection.
Causes of CHRONIC meningitis - Non infectious:
1. Neoplastic meningitis.
2. Chemical meningitis --> SAH, Drugs.
3. Uveomeningitis --> Sarco, Behcet, Wegener, Vogt-Koyanagi-Harada syndrome, Sjogren.
5. Hypertrophic pachymeningitis.