化膿性腦膜炎-英文-PPT課件

1、Purulent Meningitis in ChildrenJiang LiDepartment of NeurologyChildrens Hospital Chongqing University of Medical Sciences Acute infection of central nervous system(CNS). 90% of cases occur in the age of 1mo-5yr. The inflammation of meninges caused by various bacteria.Common features in clinical prac

2、tices include: fever, increased intracranial pressure, meningeal irritation. One of the most potentially serious infections, associated with high mortality (about 10%) and morbidity. Purulent MeningitisEtiology1.1 Pathogens:Main pathogens: Neissria meningitidis, streptoccus pneumoniae, Haemophilus i

3、nfluenzae. (2/3 of purulent meningitis are caused by these pathogens)Pathogens in special populations (neonate & 3mo infants , malnutrition, immunodeficiency): gramnegative enteric bacilli, group B streptococci, staphlococcus aureus 1.2 Major risk factors for meningitis Immature immunologic function

4、 and attenuated immunologic response to pathogens Low level of immunoglobulin, defects of complement and properdin system Immature or impaired blood-brain-barrier (BBB) Immature BBB function: maturation at about 1yr Impaired BBB: Congenial or acquired defects across mucocutaneous barrier 1.3 Access

5、of bacteria invasion Typical access-hematogenous dissemination Bacteria colonizing the mucous membranes of the nasopharynx invasion into local tissue bacteremia hematogenous seeding to the subarachnoid space Mode of transmission: Person to person contact through respiratory tract secretions or dropl

6、ets Bacteria spread to the meninges directly: through anatomic defects in the skull or head trauma Invasion from parameningeal organs: such as paranasal sinuses or middle earAccess of bacteria invasion2. Pathology Structure of meninges Characterized by leptomeningeal and perivascular infiltration wi

7、th polymorphonuclear leukocytes and an inflammatory exudate.Exudate which may be distributed from convexity of brain to basal region of cranium. Exudate is more thickness due to streptococcus pneumoniae than other pathogens.Pathology3. Clinical manifestations The younger the child is, the higher inc

8、idence of meningitis will be. -2/3 of cases occur less than 1yr of age. Mode of presentation: Acute or fulminant onset: symptoms and signs of sepsis; meningitis evolve rapidly over a few hours and death within 24 hours; usually infected with Neissria meningitides (N. meningitides). Subacute onset: P

9、recede by several days of upper respiratory tract or gastrointestinal symptoms; difficult to pinpoint the exact onset of meningitis; usually with meningitis due to Haemophilus influenzae (H influenzae) and streptoccus pneumococcus (S pneumococcus).Mode of presentation Common features of meningitis:

10、signs of systemic infection : fever(90-95%), anorexia,shock, alteration of mental status and consciousness neurological signs: increased intracranial pressure: headache, vomiting(82%), herniation meningeal irritation: nuchal rigidity(77%), kernig sign, brudzinski sign Clinical manifestationsbrudzins

11、ki sign Seizure (20-30%) Focal or generalized Due to cerebritis, infarction, electrolyte disturbances Frequently noted with H influenzae & S pneumococcal meningitis Persist after 4th day and difficult to treat with poor prognosisClinical manifestations Clinical manifestations Alteration of mental st

12、atus and consciousness Including: irritability, lethargy, stupor obtundation, coma Due to increased intracranial pressure, cerebritis, hypotension Often with pneumococcal or meningococcal meningitis Comatose patients with a poor prognosis The symptoms and signs are not evident in neonates and infant

13、s younger than 3mo of age; and patients already received irregular antibiotic therapy.Clinical manifestationsSigns of systemic infectionIncreased intracranial pressuremeningeal irritationTypical(older children)Fever, altered consciousness, seizureHeadache, vomiting, herniationnuchal rigidity, back p

14、ain, kernig sign, brudzinski signAtypical(neonate & 3mo infant )Fever,normal temperature or hypothermia; minim or subtle seizure; poor feeding;less activityScream,frown;bulging or full fontanel; widening of the suturesNot evidentComparison of the manifestations of meningitis between different age gr

15、oupsClinical manifestations4. Diagnosis Earlier diagnosis and prompt initiation of effective antibiotic treatment is critical for minimizing sequelae of purulent meningitis. Suspected cases: febrile infants with seizure, meningeal irritability, increased intracranial pressure, altered mental status

16、Pay attention to the atypical symptoms and signs in neonate, infant and patient already received irregular antibiotic therapy Diagnosis is confirmed by analysis of cerebrospinal fluid ( CSF) Suggestion bacterial meningitis Increased pressure (90%) Appearance: slightly cloudy to purulent Raised white

17、 blood cells,consisting chiefly of polymorphonuclear leukocytes Raised protein concentration, decreased glucose concentration (80%) Diagnosis Confirmation of the diagnosis: isolation from the CSF of a specific bacterial pathogen by microscopy or a positive culture or rapid antigen- detection test of

18、 CSF Gram-stained smear of CSF: identify the causative organism in 70-90% of cases CSF culture: positive in about 80% of cases. definitive diagnosis, determination of antibiotic sensitivity. PCR: amplifies bacterial DNA (H influenzae, N. meningitidis)Diagnosis5. Differential diagnosis Purulent menin

19、gitis caused by different pathogens Neissria meningitidis: Occur in epidemics (type A,C), which is more common in spring, or sporadic all the year (type B,C,Y) Sudden onset with various cutaneous signs ( petechiae, purpura, or an erythematous macular rash) Streptococcus pneumoniae: Young infants ( 1

20、yr) are most susceptible population Peak season: spring and winter Easier to have subdural effusion and hydrocephalus Easily have a protracted course and relapseDifferential diagnosis Haemophilus influenzae Occurs predominantly in infants 2mo to 2yr of age Many cases are in winter Higher incidence o

21、f subdural effusion Others pathogens: staphylococcus aureus, gramnegative enteric bacilli Special susceptible population: neonate, 3mo infants, malnutrition, immunodeficiency Severe infection, difficult to treatDifferential diagnosis Meningitis caused by other microorganisms Viral meningitis/encepha

22、litis: Less severe systemic infectious symptoms Usually not develop after 2-3weeks CSF: normal glucose Differential diagnosis Tuberculous meningitis Subacute onset and progress A history of close contact with known cases of tuberculosis Evidence of acute or healed tubercular infection on chest x-ray

23、 Tuberculin skin test : OT, PPD CSFDifferential diagnosisDiseasePressure(Kpa)aspectTotal WBC(x106/L)Protein(g/L)Glucose(mmol/L)smearsculturesnormal0.69-1.96(0.29-0.78)clear0-5(0-20)0.2-0.4(0.2-1.2)2.2-4.4-Purulentmeningitiscloudy(PMN)(1-5)(2.2)Grams stain +TuberculousmeningitisNormal or cloudy(MN)AF

24、B stain +Viral meningitis/encephalitisNormal or Normal Normal or (MN)Normal or (2ml, protein0.4g/L, Incidence: develop in 10-30% of patients, asymptomatic in 85-90% of patients; especially common in infants 4-6 month of age ( rare in children over 1yr); Causative organisms: 45% of cases of meningiti

25、s caused by H influenzae, 30% by S pneumoniae, 9% by N meningitidissubdural effusion Indications: No response to a sensitive antibiotic therapy Prolonged fever or fever reoccurring after an afebrile interval with effective treatment Bulging fontanel, widening of sutures, enlarging head circumference

26、, emesis,seizure, altered consciousness. Improved CSF profile with more serious clinical manifestationssubdural effusion Diagnosis methods: Cranial translucent test B ultrasonic examination and CT Subdural space puncture subdural effusionnormalsubdural effusion6.2 Ventriculitis6.3 hydrocephalusCompl

27、icationsCirculation of cerebrospinal fluid(CSF)6.2 Ventriculitis Usually occurs in neonates and infants (50 x106/L, Glucose400mg/L.VentriculitisCirculation of cerebrospinal fluid(CSF)6.3 hydrocephalus : Communicating hydrocephalus: adhered or destroyed arachnoid granulation around the cistern at the

28、 base of the brain Obstructive hydrocephalus: following obstructed of the cerebral aqueduct, or the foramina of Magendie and Luschka6.4 others: Deafness, blindness, paralysis, epilepsy, mental retardationComplications Treatment7.1 Antibacterial therapyTherapy principles: early treatment, antibiotics

29、 susceptible to pathogens and with high permeability through BBB, given intraveninously, enough dose, enough course of antibiotic therapy Susceptible to pathogens First choice: Cefotaxime, Ceftriaxone (3dr generation of cephalosporins, high permeability through BBB, products of metabolism also has e

30、ffect, CSF sterilization within 24h) Other choice: Penicillin, Chloromycin, Cefuroxime, Ceftazidime ( delayed effect to make CSF sterile, high incidence of relapse and deafness)Antibacterial therapyEtiologyStandard antibiotics of choiceDuration of therapyH.influenzaeCefotaxime /Ceftriaxone7-10daysN.meningitidisCefotaxime /Ceftriaxone7daysS.pneumoniaeCefotaxime /Ceftriaxone2-3weeksStaphloco