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Infectious Neurology Alison Ruiz PA-C

Case Presentation

S 48 y/o F presents to the ER with c/o headache and fever for the past two days. States started with head pain and then patient developed fever max today of 103.0. c/o rigors. Positive Nausea. No V/D. Headache is diffuse. No photophobia. No previous hx of headaches. Pt states she had a sinus infection 3 weeks ago and finished a two week course of antibiotics about 4 days ago.

History

S PMH

S Sinusitis

S PSH

S None

S FH

S Sinus infections: siblings

S Asthma mother

S DM father

S SH

S Nonsmoker

S No alcohol use

Physical Exam

S Vitals: T 98.0, P 87, R 18, BP 90/58, Pulse ox 99%

S HEENT: PERRL EOMi

S Neck: positive nuccal rigidity

S Lungs; CTA bilat. No W/R/R

S CV RRR S1S2. No murmurs

S Abd: soft NT ND NABS. No HSM. No CVAT

S Ext: No C/C/E

S Neuro: positive Brudzinski sign, negative Kernigs sign

S No focal neuro deficits

Differential Diagnosis

S Meningitis S Bacterial

S Viral

S Encephalitis

S Brain abscess

S Hemorrhage

Classic presentation and PE Findings

S Classic s/s

S Fever, stiff neck, headache and altered mental status

S Seizures

S Kernigs

S Brudzinskis

Diagnostic testing

S CBC

S WBC 20000

S Otherwise normal

S BMG

S WNL

S Blood cultures

S Pending

S Urinalysis

S WNL

S Urine culture

S Pending

S CXR

S Negative

S CT scan

S WNL

S LP

S WBC 2000mm3

S %Polymorphnuclear cells 90%

S Glucose 15 mg/dL

S Protein 400 mg/dL

S Gram stain positive

S Cytology negative

Diagnosis????

S Meningitis S Likely Bacterial based on LP results

Understanding LP Normal Parameters

Bacterial Viral Neoplastic Fungal

Opening pressures <170 mm CSF

>300mm <300mm 200mm 300mm

WBC <5 monomuclear

>1000/mm3 <1000/mm3 <500/mm3 <500/mm3

% poly-morphonuclear cells 0

>80% 1%-50% 1%-50%

1%-50%

Glucose >40 mg/dL

<40mg/dL >40mg/dL <40mg/dL <40mg/dL

Protein <50mg/dL

>200mg/dL <200mg/dL >200mg/dL >200mg/dL

Gram stain negative

Positive Negative Negative Negative

Cytology negative

Negative Negative Positive Positive

CT scan

S When and Why? S Altered mental status S Deteriorating Level of

Consciousness S Focal neuro deficit S Seizure S Papilledema S Immunocompromised state S Malignancy S Hx of stroke, focal infection, tumor S Concern for mass S Age >60 y/o

Treatment

S Antibiotic ASAP!!!! S Presumptive bacterial meningitis and

should not be delayed for neuro imaging or LP

S IV dexamethasone S 0.15mg/kg in peds S 10mg in adults S Found to improve outcomes in pt’s

with bacterial meningitis

S Admission

S What antibiotic do you use for empiric treatment in ED?

Empiric Treatment of Meningitis

Age Potential Pathogens Empiric Treatment

18-50 yrs Strep pneumo, N. meningitidis

Ceftriaxone 2g IV + Vancomycin, 15mg/kg (Rifampin if concern for resistance to strep pneumo)

>50 yrs S. pneumo, N. meningitidis, Listeria monocytogenes, aerobic gram neg bacilli

Ceftriaxone 2g IV + Ampicillin 2g IV + Vancomycin 15/mg/kg Rifampin if concern for resistance to strep pneumo)

Viral Meningitis

S Viruses include S Non-polio enteroviruses,

mumps, CMV, HSV, lympocytic chriomeningitis, adenovirus, HIV

S Distinguished from bacterial or other causes based on LP results S May be overlap of findings

between bac and viral initially S May be predominate

amount of neutrophils present in the first 24 hours

Management in Viral meningitis Admission with empiric antibiotic therapy until culture results return

OR discharge from the ED with follow up in 24 hours.

If known HSV-2 meningitis With neurologic deficits (urinary retention, weakness)

Treat with Acyclovir 10mg/kg IV q 8 h

Viral Encephalitis

S Infection of the brain parenchyma, distinguished from viral meningitis in which the infectious agent is in the subarachnoid space

S Clinically distinct neurologic abnormalities not seen in meningitis

Arbovirus or Rabies Encephalitis

Impaired Immune System

HZV Encephalitis CMV Encephalitis

Clinical Presentation

S New psychiatric symptoms

S Cognitive deficits S Aphasia, amnestic syndrome, acute confusional states

S Seizures

S Movement disorders

S Often pt will also have meningeal signs and have a coexisting meningitis

S HZV, Epstein-Barr or CMV will often present with findings outside of the CNS as well S i.e HSM, LAD

Diagnostic Imaging

MRI or CT •MRI is more sensitive •Use CT when MRI is not available •Excludes other potential lesions, such as brain abscess •Shows findings highly suggestive of HSV encephalitis • Involvement of the medial temporal and inferior frontal grey matter

EEG •HSV encephalitis shows a almost pathognomic wave •Will not be done in the ER

LP • Is the best way from the ED to diagnose •Viral cultures

Differential Diagnosis

• Meningitis, SAH • Severe headache

• Brain abscess, bacterial meninigitis • Fever and headaches

• Brain abscess, bacterial endocarditis, encephalomyelitis • If parenchymal features are present

• Lyme disease, TB, fungal and neoplastic meningitis • Less fulminant meningeal signs

Encephalitis Treatment

S HSV and possibly HZV S Acyclovir 10mg/kg IV q8h

S CMV S Gancyclovir 5mg/kg IV q12h

S Outcome is dependent on the neurologic condition at the time of antiviral therapy initiation S Pt’s in coma prior to therapy

tend to do poorly

S Diagnosis needs to be made in timely fashion

Intracranial Abscess

Three Routes to Transmit Infection the Brain

Pathogens

• Otogenic abscesses

• Most common in sinogenic and odontogenic abscesses

• From hematogenous spread • Usually include anaerobic and microaerophilic

streptococci

• Typical pathogesn due to direct implantation

• From neurosurgical procedures

Clinical Presentation

S Rarely appear acutely ill

S Fever in 50% of the patients

S Neck stiffness fewer than 50%

S Hemiparesis and seizure 1/3 of the time

S Increased ICP S Causes vomiting, confusion, obtundation

Focal Neuro Signs

• Frontal lobes • Hemiparesis

• Temporal lobes • Visual fields deficits or aphasia

• Cerebellum • Limb incoordination and

nystagmus

CT brain with contrast One or several thin, smoothly contoured rings of enhancement surrounding a low density center and surrounded by white matter edema

Other Diagnostic Testing

S Blood analysis, LP, EEG are nonspecific

S Obtain blood cultures! S Will guide management

Differential Diagnosis

• May have sudden onset with focal neuro deficits

• May have prominent fever, stiff neck and confusion

• May mimic the imaging finding of brain abscess

Treatment

Empiric Treatment Presumed Source Empiric Therapy

Otogenic

Cefotaxime 2g IV + metronidazole 500mg IV

Sinogenic

Cefotaxime 2g IV +metronidazole 500mg IV

Penetrating trauma/neurosurg procedure

Vancomycin 15mg/kg IV +Ceftazidime 2g IV

Hematogenous

Cefotaxime 2g IV + metronidazole 500mg IV

No obvious source Cefotaxime 2g IV + metronidazole 500mg IV

Case Presentation

S 28 y/o hispanic male presents to the ER. Speaks only Spanish. Translator states patient has had mild head pain for the past few weeks. He does not typically get headaches so he decided to get it checked out. He came to the emergency room because he doesn’t have a doctor. Pain has not kept patient from working. He denies other symptoms. Used Tylenol twice for the pain without relief. No visual changes. No vomiting, photophobia. Unsure if he has had fever. Positive chills, sweats.

S Moved to Chicago from Mexico 6 months ago

History

S PMH S denies

S PSH S none

S FH S doesn’t know

S SH S drinks alcohol 5-6 drinks 3 times per week S Nonsmoker

Physical Exam

S Vitals: 99.0 po, R 18, P 78, BP 140/89, Pulse Ox 100%

S HEENT NCAT PERRL EOMi

S Neck supple full rom.

S Lungs; CTA bilat. NO W/R/R

S CV RRR s1s2. NO murmurs

S Abd; soft NT ND NABS

S Ext: no C/C/E

S Neuro: No focal neuro deficits, CN II-XII grossly intact, Muscle strength 5/5 UE and LE bilat. DTR patellar tendon 2+ bilat, brachioradialis 2+ bilat, achilles 2+, triceps 2+ bilat. Pronator Drift WNL, Finger to nose WNL

S Gait normal

Differential Diagnosis

S Migraine/Tension Headache

S Infection S Meningitis, encephalitis

S Abscess

S Tumor

Diagnostic Tests

S CBC S WBC 14,000 with left shift S Hgb 11

S BMG S Glucose 180, otherwise normal

S ESR WNL

S Would you do CT?

CT Brain Findings:

Strong ring enhancing lesion with surrounding edema

No mass effect

What is the diagnosis?

S CNS Toxoplasmosis

Toxoplasmosis

S Acquired from ingestion of uncooked meat and from handling cat feces which carries parasite Toxoplasma gondii

S Immune compromised patients

S Fevers, headache, seizures and focal neuro deficits

Treatment

S Combination of Sulfadiazine (sulfonamide) +

Pyrimethamine (for protozoal infections)

S Addition of folinic acid S prevents megloblastic anemia

References

S Tintinalli 1172-1178

S Adams 1101