Meningitis ========== þ 2010 update: - no ceftriaxone under 1 month, no vanco: amp+cefotaxime - everyone over 1 month: vanco+Rocephin - Cefipime if recent UTI - give 4 mg Decadrfon first þ Molaret's Syndrome - recurrent aseptic meningitis from Herpes - basically "cold sores" on the meninges þ Meningitis Mimics - PEG-Intron for Hepatitis C - RUL or RML pneumonia can cause fever and + Brudzinski sign in kids < 12 years of age; and - Shigellosis, even before diarrhea started; and - OM, likely from cervical lymphadenitis; and - exanthema subitum. [Levy, M., E. Wong, et al. (1990). "Diseases that mimic meningitis. Analysis of 650 lumbar punctures." Clin Pediatr (Phila) 29(5): 254-255, 258-261.] A retrospective review of charts for 650 children who had lumbar puncture for suspected meningitis was undertaken to determine the characteristics of patients with and without meningitis, identify other conditions suggesting meningitis, and evaluate the predictive value of signs and symptoms of meningitis. The incidence of positive lumbar punctures increased with patient age. Younger infants did not present with classical features of meningitis. Bulging fontanel, lethargy, and irritability were nonspecific symptoms. Vomiting and headache, although not specific, proved to be more sensitive indicators of meningeal infection. Most patients with meningitis (75%) had at least one sign of meningeal irritation, but so did 25% of patients without meningitis. Brudzinski's sign was not specific. In contrast, nuchal rigidity and Kernig's sign had high predictive value. Up to age five, the diseases most often suggesting meningitis were right-sided pneumonia, gastroenteritis, otitis, tonsillitis, exanthema subitum, and urinary tract infections. Of 171 patients with febrile convulsion, one (0.5%) had bacterial meningitis and four had aseptic meningitis. þ Photophobia - highly specific, not very sensitive [Amarilyo, G., A. Alper, et al. (2011). "Diagnostic accuracy of clinical symptoms and signs in children with meningitis." Pediatr Emerg Care 27(3): 196-199.] BACKGROUND: The diagnostic accuracy of the classic symptoms and signs of meningitis in infants and children has not been established. METHODS: All children aged 2 months to 16 years with clinically suspected meningitis were eligible for this prospective cohort study at 2 large medical centers between February 2006 and October 2007. Exclusion criteria were severe chronic disease, severe immune deficiency, or idiopathic intracranial hypertension. The emergency department physician obtained information on clinical symptoms and signs and cerebrospinal fluid analysis. Meningitis was defined as white blood cell count of 6 or higher per microliter of cerebrospinal fluid. RESULTS: A total of 108 patients with suspected meningitis were enrolled. Meningitis was diagnosed in 58 patients (53.7%; 6 bacterial and 52 aseptic). Sensitivity and specificity were 76% and 53% for headache (among the verbal patients) and 71% and 62% for vomiting, respectively. Photophobia was highly specific (88%) but had low sensitivity (28%). Clinical examination revealed nuchal rigidity (in patients without open fontanel) in 32 (65%) of the patients with meningitis and in 10 (33%) of the patients without meningitis. Brudzinski and Kernig signs were present in 51% and 27% of the patients with meningitis, respectively, and had relatively high positive predictive values (81% and 77%, respectively). Bulging fontanel in patients with open fontanel was present in 50% of the patients with meningitis but had a positive predictive value of only 38%. CONCLUSIONS: Classic clinical diagnostic signs have limited value in establishing the diagnosis of meningitis in children and should not be the sole determinants for referral to further diagnostic testing and lumbar puncture. þ Meningococcemia - good review: [Kirsch EA. Pathophysiology, treatment and outcome of meningococcemia: A review in recent experience. Pediatric Infectious Disease Journal 1996;15:967-979.] þ Ventriculoperitoneal (VP) Shunts - 2/3 of patients with VP shunts will have a problem with it. - Sx of malfunction: headache, nausea, vomiting, lethargy, ataxia, coma. - May obstruct proximally from tissue debris or migration of catheter into parenchyma; kinking, infection or venous occlusion can plug the distal end. - About a 15% rate of infections from placement, usually with low-virulent skin flora, but about 5-10% with bad gram negatives. - Lack of fever, normal cell count, normal glucose, and normal protein don't exclude infection. - Good review: [Key CB. Cerebrospinal fluid shunt complications: an emergency medicine perspective. Pediatric Emergency Care 1995;11:265-273.] þ See also pediatrics section on meningitis: þ Using urine dipsticks for CSF - Can use urine dipsticks to check for meningitis with 97% sensitivity; check for protein, glucose, leukocyte esterase (LET) [Moosa AA. Lancet 1995;345:1290-1.] þ Blood Cultures for Meningitis - In cases of meningitis caused by H. influenza, S. pneumoniae or N. meningitidus, blood cultures will be positive approximately 50% of the time. Ref: Rosen's CD ROM line 29830 þ Cryptococcal Meningitis - Diagnosis: + Budding organisms will be seen in an india ink stain in only one third of cases of cryptococcal meningitis. + Testing for cryptococcal antigen will increase the diagnostic sensitivity and specificity to 90%. Ref: Rosen's CD ROM line 29807 þ LP findings in infants and children þ Meningitis with normal CSF is possible þ Papilledema in Meningitis? - Papilledema is uncommon with meningitis. If present, other CNS pathology including subdural empyema and a cerebral abscess must be ruled out. Ref: Rosen's CD ROM line 29771 þ Meningitis: Do you need to CT before LP? - based on idea that increased ICP, which _is_ found in meningitis, may cause herniation if LP performed. However, need increased ICP _plus_ obstruction, which is rare in meningitis, to cause herniation. - The medical literature, the Advanced Neurological Life Support Course (whatever that is), and a survey of 14 neurologists, support "CT before LP" for uncomplicated meningitis. - Complications from LP in patients _with_papilledema_ only 0-6%. [Archer BD. Computed tomography before lumpar puncture in acute meningitis: a review of the risks and benefits. Can Med Assoc J 1993; 148(6):961.] - additional commentary: þ Meningismus Organisms and Antibiotics: -------------------------- þ Meningitis in neontates: 0-2 weeks E. Coli Group B strep Listeria enterococcus 3-6 weeks above + H. Flu. (much less now with routine immunization for this) pneumococcus meningococcus þ Meningitis in children, adolescents and adults (above 2 months): - pneumococcus, meningococcus - Per Med Letter 43(1111-1112)m Aug 20, 2001 use: + high-dose Rocephin (ceftriaxone 2 g [50 mg/kg] IV BID) or Claforan (cefotaxime 2 g [50 mg/kg] IV BID) + AND Vancomycin 1 g [15 mg/kg] IV QID - H. Flu used to be a problem in the younger group, but no more - At Mercy as of April, 1998, there are PCN and cephalosporin-resistant pneumococci showing up, so recommendation for everyone with meningitis is Ceftriaxone + Vancomycin 60 mg/kg/day divided QID (Mercy pharmacy) (may need up to 4 g/day to get adequate levels per Med Ltr) þ in elderly: Listeria, pneumococcus, meningococcus, gram negatives Third generation cephalosporins have no activity against Listeria or enterococcus, so if may be Listeria (very young or very old) or enterococcus, add ampicillin to a third generation cephalosporin. Tintinalli 4E summary: ---------------------- 0-3 months Claforan (cefotaxime) 50 mg/kg BID + Ampicillin 50 mg/kg BID (Ampicillin to cover Group B Strep = enterococcus) 3 mo-50 yrs Rocephin (ceftriaxone) 50 mg/kg (up to 2 g) BID > 50 yrs Rocephin (ceftriaxone) 2 g BID + Ampicillin 2 g Q4H (Ampicillin to cover Listeria) CSF leak Rocephin (ceftriaxone) 2 g BID CSF shunt, Vancomycin 25 mg/kg IV load + neurosurg, Fortaz (ceftazidime) 2 g TID penetrating immunocompr Vanco and Fortaz as above+ Ampicillin 2g IV Q4H After Closed or Open Head Trauma: --------------------------------- þ post surgical: staph, strep, Gram negatives þ soon after injury (2-3 days): always pneumococcus þ later after injury (4-7 days): staph, Gram negatives, Pseudomonas Third generation cephalosporins: -------------------------------- þ ones that don't get Pseudomonas: ceftriaxone, ceforaxime, ceftizoxime (better against Gram positives) þ ones that get Pseudomonas: cefoperazone, ceftazdime (relatively poor against Staph) Prophylaxis of Exposures: ------------------------- (per Dr. Lumish, Infectious Diseases, Mercy Hospital of Pittsburgh, June 8 1994): - immediate family contacts of those with meningococcus: carriage rate of up to 50% as opposed to about 5% in the general population. - secondary attack rate from an index case: about 1:1,000; prophylaxis can reduce further. - 2/3 of secondary attacks occur within the first four days of onset of the index's illness; the other 1/3 within 30 days. - Who to prophylax? Those living with the index case the week prior. Nurses or respiratory therapists who have been with the patient for a full shift. Plain ED personnel don't need to receive prophylaxis. - Consider also giving polyvalent meningococcal vaccine (protects against most strains except for B) to family. þ Tests for Meningitis - Latex agglutination and countercurrent immunoelectrophoresis (CIE) are two rapid methods for identifying an organism in bacterial meningitis. In general, latex agglutination is generally preferred over CIE because it is more sensitive than CIE, and can be performed more rapidly. Reference: Tintinalli 3rd ed. p 829