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CNS Infections Sarah McPherson Aug. 15, 2002 14 yo male presents with headache ane fever X 24 hrs. Previously well. Seen in doctor’s office and sent to ED after a witnessed focal seizure involving the right arm. Other history unremarkable O/E: Hr 100, BP 110/70, Temp 39.5 normal mental status, no nuchal rigidity normal neuro exam What would you do???? Clinical presentation of meningitis Classic triad of bacteral meningitis (< 2/3 of presentations): fever, nuchal rigidity, altered mental status also present as headaches, seizures (focal or generalized, weight loss, night sweats, septic shock physical exam: Kernig’s (unable to extend knee when pateint suline with hip flexed) Brudinski’s (flex neck and the hips also flex OR flex hip on one side and see similar movement of the other hip) Causes of meningitis Infectious Infectious Bacterial: fungal: cryptococcus coccidioides candida blastomyces Parasites: S. pneumo N meningitidis L monocytogenes H flu S. aureus E coli GBS Viral: HSV enterovirus HIV varicella toxopasma Rickettsia: Rocky Mountain spotted fever Causes of meningitis Drugs NSAID trimethoprim isoniazid Systemic disease Serum sickness vasculitis SLE sarcoidosis Diagnosis The LP: Cell count: < 5 WBC, < 1 PMN gram stain: no organism xanthochromia: none CSF-serum glucose: 0.6:1 protein: 15-45 mg/dl Diagnosis When should you CT before LP??? Profoundly altered mental status papilledema focal neuro deficit minimal or absent fever recent head trauma recent onset seizure Diagnosis What if you have a VP shunt??? Infection rates 2.6-10% mostly in first few months after insertion mostly infected by skin flora (S aureus, coag - staph, propionobacterium) needle aspirate the reservoir (~25% better than LP at identifying pathogen) Back to the Case... CT head normal LP: 40 WBC 3 PMN 3 RBC CSF glucose low (normal serum glucose) protein elevated negative gram stain What now??? Definitive therapy Bacterial Meningitis: 3rd generation cephalosporin add Vanco if in area where drug resistant S. pneumo is prevelant add ampicillin to cover Listeria (< 3 months, > 50 years) Definitive therapy What if your gram stain shows gramnegative coccobacilli??? The controversy of pre-treatment with steroids... Steroids... Shown to decrease neurologic and audiologic sequelae in children > 2 months of age with H. flu infections benefit to adult patients or infections other than H. flu is less clear Recommendation: treat children with gram negative coccobacilli on gram stain with 0.15 mg/kg of Dexamethasone just before giving antibiotics and then q6h X 4 days Another Case 22 yo girl presents with purpuric rash, nuchal rigidity, temp 39.1, HR 110, BP 95/60, with altered mental status How would this presentation alter your approach? ABC’s first, blood cultures, Antibiotics then LP Aseptic meningitis Typically present as fever and nuchal rigidity, may have headache, N&V CSF may show increased WBC with increased lymphocytes; normal to slightly elevated protein; normal gram stain Aseptic meningitis Management: supportive relief of headache, fever, and dehydration medical if WBC on gram stain most clinicans will start on empiric antibiotics pending C&S if evidence of primary HSV infection, acyclovir (oral 200 5X/day for 10 days) 70 yo man presents with fever 38.5 X 6 hr, headache, altered LOC and aphasia, HR 85, BP 105/80 CT shows edema of the right temporal lobe LP 30 WBC, increased protein, normal gram stain Viral encephalitits Rare typically present with fever, headache, altered LOC, behavioral or speech disturbnce, focal neuro deficits, seizures CSF: mononuclear cell pleocytosis; elevated protein; normal gram stain; PCR for HSV, CMV, HHV-6, enterovirus (99% sens and 94% spec for HSV) CT, MRI, EEG may be helpful Herpes Encephalitis Neonatal CNS involvement in majority infants with herpetic disease in the newborn period CSF PCR is the gold standard treatment : Acyclovir 30mh/kg/d divided q8h with antiviral decreased mortality from 50% to 15% (pts with CNS involvement) 2/3 will have long term neurologic sequelae despite treatment Herpes Encephalitits HSE most common cause of focal encephalitis 50% are > 50 yoa without antiviral mortality > 80% Treatment: Acyclovir 10 mg/kg q8h Prognosis: if GCS < 6 outcome is poor if treatment is started in < 4 days from onset of symptoms survival increases from 72 to 92% with acyclovir 30% normal or minimal neuro impairment, 9% moderate, 53% dead or severe impairment West Nile Virus First isolated in 1937 in Uganda first isolated in the Us in 1999 now found in Ontario, Quebec, Manitoba and possibly SK transmitted by mosquito in an area hwere West Nile is circulating ~ 1% of mosquitos will carry it and there is an ~1% risk of infection after bite from a + mosquito symptoms: fever, headache, myalgia, arthralgia, lymphadenopathy, maculopapular or roseloar rash on trunk or extremitites, nuchal rigidity, seizure, altered LOC, muscle weakness increased fatality in elderly pop’n treatment supportive of hospitalized patients mortality ranges from 3-15% 45 yo man with HIV presents with headache and fever neuro exam normal, temp 38.2, normal vitals What next???? Normal CT head but when infused shows ring enhancing lesion DX? Toxoplasmosis Rx? Admission, pyrimethamine 200 mg po then 50 -100 mg qd plus clindamycin 900 iv q6h CNS infection in the HIV patient CNS infection occurs in 75-90% of patients with AIDS infections are the predominant cause of new neuro symptoms/signs toxoplasma gondii: most common cause of focal encephalitits DX: contrast enhanced CT or MRI showing ringed lesion; LP for Ab to toxo Ag Rx: pyrimethamine + clinda or sulfadiazine CNS infection in the HIV patient Cryptococcus neoformans causes focal lesion or diffuse encephalitits Dx: India ink stain, fungal culture,cryptococcal Ag in CSF Rx: Ampho B iv HSV M. tuberuculosis Nocardia all the bacteria that nonimmunosuppressed patients have new neuro symptoms/signs +/- fever Enhanced CT head LP for all the normal stuff + India ink stain, fungal culture, viral PCR’s, Toxo Ab, Crypto Ag, Acid fast stain 25 yo women presents with back pain X 2 days. She has no other concerns. O/E afebrile, hemodynamically stable, normal neuro exam, you notice track marks on her arms. She admits to ongoing IVDU. What would you do next? What are your concerns? Epidural Abscess Risk factors: IVDU recent spinal or epidural anaesthesia systemic infection Clinical features: back pain focal neuro deficits fever (83% of the time) all IVDUers with back pain should be considered infectious until proven otherwise (osteo vs epidural abscess) Epidural Abscess Dx: CT, if negative and clinical suspicion is high then need an MRI Rx: emergent surgical debridement 3rd generation cephalosporin + Flagyl