Meningitis Flashcards
Which drugs to use if the gram-stained smear of CSF indicates pneumococcal or meningococcal disease?
Penicillin G or Cefotaxime/Ceftriaxone.
Pneumococcal: 2 weeks
Meningococcal: 1 week
Penicillin G - Dose and route
3g x 4 IV for 21 d
Ceftriaxone - Dose and route
4g x 1 IV
Meningococcal - 7 d
Pneumococcal - 10-14 days
Gram (-) - 14-21 d
Ceftriaxone - MoA
3rd generation cephalosporin. Inhibits bacterial cell wall synthesis
Ceftriaxone - Adverse effects
Hypersensitivity (rare, cross-sensitivity to penicillins):
Anaphylaxis, fever, skin rashes, nephritis, granulocytopenia, hemolytic anemia
Local irritation: pain after IM injection, thrombophlebitis after IV
Renal toxicity (intersitial nephritis, tubular necrosis)
Ceftriaxone - Contraindications
Allergy to cephalosporins and penicillin
Newborns with jaundice
Hypoalbuminemia
Alternative drugs for patients with penicillin allergy
Meropenem and vancomycin/chloramphenicol
Meropenem - Dose and route
2g x 3 for 10-14 days
Meropenem - MoA
Carbapenem. Inhibits bacterial cell wall synthesis
Meropenem - Adverse effects
Cross-sensitivity with penicillin allergy Seizures in patients with epilepsy Diarrhea Vomiting Anemia Leukopenia Thrombocytopenia Altered bleeding time
Meropenem - Contraindications
Allergy to penicillins and cephalosporins
Caution in patients with brain damage and decreased kidney function
Vancomycin/Chloramphenicol - Dose and route
Vancomycin: 30-60 mg/kg/day
Chloramphenicol: 1g x 4 IV for 10-14 days
Vancomycin - MoA
Inhibit bacterial cell wall synthesis
Vancomycin - Adverse effects
Reduced nephro- & ototoxicity now compared to before
Hypotension and erythematous rash with to quick infusion (called red man syndrome)
Vestibular dysfunction (ataxia, vertigo, nystagmus, nausea)
Cochlear dysfunction (tinnitus, hearing loss)
Vancomycin - Contraindications
Patients with reduced hearing
Caution in patients with decreased renal function
Vancomycin - Interactions
Increased nephro- and ototoxicity with aminoglycosides, amphotericin B
Chloramphenicol - MoA
Protein synthesis inhibitor.
Chloramphenicol - Adverse effects
Gray baby syndrome characterized by cyanosis, weakness, respiratory depression, and shock
Reversible, dose-dependent anemia caused by blockade of iron incorporation into heme
Nausea, vomiting, diarrhea,
Oral/vaginal candidiasis
Chloramphenicol - Contraindications
Pregnancy
Caution in kidney and liver dysfunction, premature, newborns
Prophyria
Bacterial Meningitis- Diagnosis
Clinical presentation:
- Triad: fever, headache, nuchal rigidity (Kernig & Brudzinski’s sign)
- Decreased level of consciousness and raised ICP (Cushing reflex; bradycardia, HTN, irregular resp)
- Rash of meningococcemia; Tumbler test
Tests:
- Blood culture
- CBC (Leukocytes!), ESR, CRP, Electrolytes, Glucose, INR, APTT, Renal and liver function tests
- Urine pneumococcal antigen test
- LP: CSF analysis; CSF culture, CSF Gram’s stain, CSF bacterial PCR. CSF glucose is low (glucose<2,2 mmol/L, <40 mg/dL), neutrophils predominate, proteins>0,45g/L)
- Latex agglutination test
- Limunus lysate: Gram (-) meningitis
Imaging:
MRI
CT
Biopsy: petechial skin lesions –> Gram’s stain
Culture of throat swab: meningococcal disease
Bacterial meningitis- Differential diagnosis
- HSV encephalitis
- Ehlirchioses
- Rickettsial disease
- Brain abscess
- Subarachnoid hemorrhage
- Tumor
- Meninigtis related to inflammatory disorders – SLE or Behet
- Pituitary apoplexy
- Subacute meningitis – M. tuberculosis & C. neoformans
Meningitis - Empirical antibiotic therapy + Doses
Infants: Ampicillin+ Ceftriaxone
Immunocompotent children > 3 months, Adults <55 y: Ceftriaxone + Vancomycin
Adults> 55, alcoholism etc: Ceftriaxone + Ampicillin + Vancomycin
Hospital acquired, post-trauma, post-surgery: Ampicillin + Meropenem + Vancomycin
Ampicillin- 3gX4 IV
Ceftriaxone - 4g X 1 IV
Vancomycin - 60 mg/kg x1 IV
Meropenem - 2g X 3IV
Acyclovir - MoA
Nucleoside analogue
Acyclovir - Adverse effects
Headache, GI disturbances, rash
Acyclovir - Interactions
Increases concentration of lithium and cyclosporin
Acyclovir - Contraindication
Hypersensitivity to valacyclovir and acyclovir
Acyclovir - Dose
10 mg/kg every 8 h IV followed by 800 mg X 5 daily PO for 10-14 days.
Vancomycin - Dose
30-60 mg/kg divided into 2-3 doses
Viral meningitis - Diagnose
CBC (Leukocytes!), CRP, ESR, Electrolytes, Glucose, Renal and liver function tests, Creatinine, glucose, amylase, lipase
CSF analysis: Pleocytosis (Lymphocutes predominate), Normal or slightly elevated protein concentration 20-80 mg/dL, Normal glucose concentration, Normal or mild elevated opening pressure 100-350 mmH20, Organism NOT seen on Gram stain of CSF, ) Total CSF cell count in viral meningitis is 25-500/uL
PCR of viral-specific DNA or RNA from CSF
PCR of throat washings or stool
Culture: CSF, throat swab, stool blood, urine
MRI: altered consciousness, seizures, neurologic signs
Viral meningitis- Differential Diagnosis
Untreated or partially treated bacterial meningitis
Bacteria, fungal, tuberculous, spirochetal or other infectious causes of meningitis
Neoplastic meningitis
Viral Meningitis - Treatment
Symptomatic; Analgesics, antipyretics, antiemetic. Monitor fluid and electrolyte status
Immunocompromised, neurologic alterations, elderly, seriously ill pts:
Acyclovir
Meningitis - Vaccines
Meningococcal B
Pneumococcal conjugate vaccine (PCV)
Pneumococcal polysaccharide vaccine (PPV)
BCG
Listeria Meningitis - Treatment
Ampicillin 3 g X 4 IV + Gentamycin - 2mg/kg IV loading dose then 7,5 mg/kg per day given every 8 h
Duration: 21 days
Viral meningitis- Most common pathogens
Enteroviruses!
VZV, HSV (type 2) HIV, Arbo
