Meningitis:Meningitis:The BasicsThe Basics

Steven M. Snodgrass M.D.Steven M. Snodgrass M.D.

What is meningitis ?What is meningitis ?

Inflammation of the Inflammation of the meninges/leptomeninges – the pia, meninges/leptomeninges – the pia, arachnoid, and dura mater.arachnoid, and dura mater.

Can have various causes – bacteria, Can have various causes – bacteria, viruses, fungus.viruses, fungus.

How it happensHow it happens

NP colonization of susceptible individual NP colonization of susceptible individual and invasion of respiratory tractand invasion of respiratory tract

Invasion of bloodstream (Bacteremia)Invasion of bloodstream (Bacteremia) Choroid plexitisChoroid plexitis Spread to meningesSpread to meninges Ventriculitis and increased intracranial Ventriculitis and increased intracranial

pressurepressure Recruitment of inflammatory mediators Recruitment of inflammatory mediators

How it happensHow it happens

Damage to blood-brain barrier leads Damage to blood-brain barrier leads to cerebral edemato cerebral edema

Endothelial cell damage, thrombosisEndothelial cell damage, thrombosis Increase in CSF protein, decrease in Increase in CSF protein, decrease in

glucose from hypoxia, decreased glucose from hypoxia, decreased aerobic metabolismaerobic metabolism

Infarction, Seizures, Abscess Infarction, Seizures, Abscess formationformation

Typical presentationsTypical presentations

You are seeing a 14 day old infant in You are seeing a 14 day old infant in the emergency room with a 2 day the emergency room with a 2 day history of congestion. Parents note history of congestion. Parents note infant to be increasingly irritable and infant to be increasingly irritable and lethargic, sleeping through feeds, lethargic, sleeping through feeds, multiple episodes of vomiting, difficult multiple episodes of vomiting, difficult to console. Fever of 103 rectal. Infant to console. Fever of 103 rectal. Infant looks pale and feels cool with HR of looks pale and feels cool with HR of 225. A spinal tap shows 5000 white 225. A spinal tap shows 5000 white blood cells and a gram stain reveals blood cells and a gram stain reveals gram negative rods. gram negative rods.

Typical presentationsTypical presentations

You are seeing a 15 yo high school You are seeing a 15 yo high school student in your office with a 24 hour student in your office with a 24 hour history of lethargy, repeated history of lethargy, repeated vomiting, and fever to 102. On exam vomiting, and fever to 102. On exam he is unable to touch his chin to his he is unable to touch his chin to his chest and resists full extension of his chest and resists full extension of his knee while lying flat. knee while lying flat.

Pathogens of Bacterial Pathogens of Bacterial MeningitisMeningitis

Neonates (<1mo) :Neonates (<1mo) :– Group B streptococcus, E. coli, ListeriaGroup B streptococcus, E. coli, Listeria

Infants (1-24 mos):Infants (1-24 mos):– Haemophilus influenzae type B, Haemophilus influenzae type B,

Streptococcus pneumoniae, Neisseria Streptococcus pneumoniae, Neisseria meningitidismeningitidis

Children (>2yo):Children (>2yo):– Neisseria (meningococcus), Strep Neisseria (meningococcus), Strep

pneumo (pneumococcus), H. flupneumo (pneumococcus), H. flu

Meningococcemia

Gram negative diplococciGram negative diplococci

DiagnosisDiagnosis

Must maintain a high index of Must maintain a high index of suspicion in many casessuspicion in many cases

Gold standard is positive culture in Gold standard is positive culture in CSF, may have CSF positive gram CSF, may have CSF positive gram stainstain

Lumbar puncture and CSF also show Lumbar puncture and CSF also show pleocytosis, increased protein, and pleocytosis, increased protein, and hypoglycorrheahypoglycorrhea

CSF findingsCSF findings

ComponenComponentt

NormalNormal BacterialBacterial

meningitimeningitiss

Viral Viral

meningitimeningitiss

HerpeticHerpetic

encephaliencephalitistis

SpirochetSpirochetalal

encephaliencephalitistis

GlucoseGlucose

mg/dLmg/dL40-8040-80 <30<30 >30>30 >30>30 40-11040-110

ProteinProtein

mg/dLmg/dL20-5020-50 >100>100 50-10050-100 >75>75 15-15015-150

WBCsWBCs 0-60-6 >1000>1000 100-500100-500 10-100010-1000 20-50020-500

NeutrophilNeutrophilss

00 >50 %>50 % <20 %<20 % <50 %<50 % <10 %<10 %

RBCsRBCs 0-20-2 0-100-10 0-20-2 100-500100-500 0-20-2

How much does it happenHow much does it happen11

Pittsburgh similar to US in generalPittsburgh similar to US in general– For 5-17 yo in 2006:For 5-17 yo in 2006:– Neisseria 0.4-0.5 cases per 100,000 with Neisseria 0.4-0.5 cases per 100,000 with

50% meningitis and 8% mortality50% meningitis and 8% mortality– Pneumococcus 3.3 cases per 100,000 with Pneumococcus 3.3 cases per 100,000 with

6% meningitis and 2.5 % mortality6% meningitis and 2.5 % mortality

– 237 total cases of pneumococcal meningitis237 total cases of pneumococcal meningitis– 68 total cases of meningococcal meningitis68 total cases of meningococcal meningitis

1. http://www.cdc.gov/ncidod/dbmd/abcs/survreports.htm

We’re luckyWe’re lucky

1.1 cases per 100,000 in US in 2004 1.1 cases per 100,000 in US in 2004 as compared to:as compared to:

Cases per 100,000:Cases per 100,000:– Pakistan 4.4Pakistan 4.4– Haiti 6.1Haiti 6.1– Iraq 5.9Iraq 5.9– China 7.7China 7.7– India 53.5India 53.5

TreatmentTreatment

Antibiotics – Penicillins, Vancomycin, Antibiotics – Penicillins, Vancomycin, CephalosporinsCephalosporins

? Steroids - Dexamethasone? Steroids - Dexamethasone Treat underlying hemodynamic Treat underlying hemodynamic

compromise (shock) and other compromise (shock) and other complicationscomplications

Monitor for and treat sequelaeMonitor for and treat sequelae

Complications and SequelaeComplications and Sequelae

Complications:Complications: Shock/SepsisShock/Sepsis Cerebral edemaCerebral edema Subdural empyemaSubdural empyema Subdural effusionSubdural effusion VentriculitisVentriculitis AbscessAbscess SeizuresSeizures

Sequelae:Sequelae: DeafnessDeafness Developmental Developmental

delay, cognitive delay, cognitive impairmentsimpairments

Chronic seizure Chronic seizure disorderdisorder

HydrocephalusHydrocephalus

Vaccines…Vaccines…

MenactraMenactra– Protects against four most common Protects against four most common

serogroups of Neisseria A, C, Y and W-serogroups of Neisseria A, C, Y and W-135135

– Most cases in infants due to serogroup BMost cases in infants due to serogroup B– Adolescents and adults aged 11-55 yoAdolescents and adults aged 11-55 yo– Give at entry to H.S., college dorm Give at entry to H.S., college dorm

residents, other at risk groupsresidents, other at risk groups– Conjugate vaccine as compared to MPSVConjugate vaccine as compared to MPSV

ProphylaxisProphylaxis

Most often for meningococcal Most often for meningococcal meningitis and Haemophilus meningitis and Haemophilus influenzaeinfluenzae

Close contactsClose contacts Rifampin or CiprofloxacinRifampin or Ciprofloxacin

Steve SnodgrassSteve Snodgrass Children’s Hospital of Pittsburgh of Children’s Hospital of Pittsburgh of

UPMCUPMC Steven.Snodgrass@chp.eduSteven.Snodgrass@chp.edu Please e-mail with questions or Please e-mail with questions or

commentscomments