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Meningitis
infection of the cerebral spinal fluid (CSF) results in inflammation of the meningesseverity of meningitis varies greatly virulence of the infecting microorganism immune status of the patient TERM 2
Symptoms of meningitis
DEFINITION 2 Early Stiff neck (nuchal rigidity) Severe headache worst headache of life Chills & fever Later Mental confusion, stupor, & coma TERM 3
Types of meningitis
DEFINITION 3 Acute bacterial - most severe rapid onset - a few hours to 1 or 2 days Acute aseptic not able to culture bacteria or fungi caused by a virus milder symptoms & often self- limited Chronic - slow onset insidious onset of symptoms - weeks usually caused by fungi TERM 4
Causes of meningitis
DEFINITION 4 Bacteria - Red are normal flora Streptococcus pneumoniae Neisseria meningitidis* Haemophilus influenzae* Streptococcus agalactiae Listeria monocytogenes Fungi Cryptococcus neoformans Coccidioides immitis Viruses - Enteroviruses (most common viral cause) TERM 5
Epidemiology / Pathology of Bacterial
Meningitis
DEFINITION 5 Nasopharyngeal colonization acquisition of a new microorganism (i.e. exogenous origin) local infection or colonization without overt disease Local invasion microorganisms breach mucosal barrier enter bloodstream (bacteremia & septicemia)
Epidemiology / Pathology of Bacterial
Meningitis -CNS invasion
Central nervous system invasion - mechanism not known immune defense mechanisms in CNS are inadequate low level of antibodies & complement needed to combat encapsulated microorganisms most microorganisms that cause meningitis have a capsuleAntibodies andComplement cantget into CNS-but phagocytic cells canWhich is why you get inflamation TERM 7
Properties of polysaccharide capsule in
meningitis
DEFINITION 7 enhances virulence by its antiphagocytic activity defines serological group of microorganism antigen detected in spinal fluid of patient antigen used in vaccine(s) TERM 8
Meningitis is a medical emergency
DEFINITION 8 rapid diagnosis is criticalbegin antibiotic treatment immediately aimed at most likely pathogen use antibiotics that achieve MBC in CSF mortality rate is ~15 - 25% even with antibiotic treatmentcomplications often occurhearing defects & mental retardation TERM 9
Diagnosis of meningitis
DEFINITION 9 clinical symptoms After symptoms are noticed , then do a lumbar puncture lumbar puncture CSF analysis Gram stain, culture & bacterial antigen tests blood culture TERM 10
CSF analysis
DEFINITION 10 Etiology healthy bacterial Pressure normal increasedCells low increased (PMNs) Protein normal increasedGlucose normal decreased
Haemophilus influenzae - Prevention
prevention capsular polysaccharide-protein conjugate vaccine (for type b only) rifampin chemoprophylaxis for close contacts TERM 17
Neisseria meningitidis - I dentification
DEFINITION 17 facultative Gram-negative diplococcus oxidase positiveferments glucose & maltose (N. gonorrhoeae ferments glucose only) normal habitat is human upper respiratory tract / nasopharynx ~5 - 35% of individuals colonized TERM 18
Transmission of N. meningitidis
DEFINITION 18 exchange of respiratory and throat secretions i.e. coughing, kissing, etc. (not just breathing respired air) usually in close contacts same household day-care centers military barracks prisons college dormitories - highest rate of disease complement deficiency (C5-C9) at increased risk TERM 19
Virulence factors of N. meningitidis
DEFINITION 19 pili - helps to adhere polysaccharide capsule (13 serogroups) endotoxin IgA protease TERM 20
N. meningitidis epidemiology of
infection
DEFINITION 20 ~ 13 serogroups based on capsular polysaccharideserogroups A, B, C, & W-135 cause vast majority of typed casesserogroup B causes most (~ 25
- 50%) of theseSerogroups A, C, Y, W-135 are vaccine preventable
N. meningitidis vaccine(s)
capsular polysaccharide vaccine (MPSV4) not very effective in individuals < 18 years old recommended vaccine for > 55 years-old capsular polysaccharide-protein conjugate vaccine(s) (MCV4 licensed in 2005 & MenACWY-CRM licensed in 2010) for 2- 55 year-olds effective in children, adolescents, & adults All vaccines contain serogroups A, C, Y, & W- none provide protection against serogroup B B capsular polysaccharide similar to polysialic acid containing glycoproteins present in brain (tolerance & cross-reactivity) TERM 22
Recommendations for Meningococcal
Vaccine(s
DEFINITION 22 General Population (MCV4 or MenACWY-CRM) all 11- years old or at entry into high school Groups at Risk College freshman living in dormitories Military recruits Travelers to hyperendemic/epidemic regions Individuals with complement deficiencies Microbiologists at increased risk TERM 23
Chemoprophylaxis & Treatment of
Meningococcal Disease
DEFINITION 23 Chemoprophylaxis Rifampin PO Children & adults or Ciprofloxacin PO Adults**** or Ceftriaxone IV Children <15 & adults * may affect reliability of oral contraceptivesnot recommended for pregnant women, teratogenic in lab animals* not recommended for individuals < 18 or for pregnant and lactating women, cartilage damage in immature lab animals TERM 24
Bordetella pertusis Gram-negative short rod
(coccobacillus)
DEFINITION 24 whooping cough / pertusishabitat human upper respiratory tracttransmission respiratory droplets very contagious ~90% of unvaccinated children living with someone with pertusis & ~50-80% of unvaccinated children who attend school/daycare with someone with pertusis will become infected TERM 25
Bordetella pertusis - Virulence factors
DEFINITION 25 pili capsule endotoxin exotoxin
Pertusis -Facts
half of infants who get pertusis are infected by their parentsCA requires pertusis booster immunization all 7th graders prior to entering schoolIf you have young children or are around them frequently Get the booster!
