1、Introduction?Bacterial meningitis is an inflammation of the leptomenings, usually causing by bacterial infection.?Bacterial meningitis may present acutely (symptoms evolving rapidly over 1-24 hours), subacutely (symptoms evolving over 1-7days), or chronically (symptoms evolving over more than 1 week
2、).Introduction?Annual incidence in the developed countries is approximately 5-10 per 100000. ?30000 infants and children develop bacterial meningitis in United States each year. ?Approximately 90 per cent of cases occur in children during the first 5 years of life.Introduction?Cases under age 2 year
3、s account for almost 75% of all cases and incidence is the highest in early childhood at age 6-12 months than in any other period of life.?There are significant difference in the incidence of bacterial meningitis by season.Etiology?Causative organisms vary with patient age, with three bacteria accou
4、nting for over three-quarters of all cases:?Neisseria meningitidis (meningococcus)?Haemophilus influenzae (if very young and unvaccinated)?Streptococcus pneumoniae ( pneumococcus)Etiology?Other organisms ?Neonates and infants at age 2-3 months ?Escherichia coli?B-haemolytic streptococci?Staphylococc
5、us aureus?Staphylococcusepidermidis?Listeria monocytogenesEtiology?Elderly and immunocompromised?Listeria monocytogenes?Gram negative bacteria?Hospital-acquired infections?Klebsiella?Escherichia coli?Pseudomonas?Staphylococcus aureusEtiology?Themostcommon organisms?Neonates and infants under the age
6、 of 2months?Escherichia coli ?Pseudomonas ?Group B Streptococcus?Staphylococcus aureusEtiology?Children over 2 months?Haemophilus influenzae type b?Neisseria meningitidis?Streptococcus pneumoniae?Children over 12 years?Neisseria meningitidis?Streptococcus pneumoniaeEtiology?Major routes of leptomeni
7、ng infection?Bacteria are mainly from blood.?Uncommonly, meningitis occurs by direct extension from nearly focus (mastoiditis, sinusitis) or by direct invasion (dermoid sinus tract, head trauma, meningo-myelocele).Pathogenesis?Susceptibility of bacterial infection on CNSin the children ?Immaturity o
8、f immune systems?Nonspecific immune?Insufficient barrier(Blood-brain barrier)?Insufficient complement activity?Insufficient chemotaxis of neutrophils?Insufficient function of monocyte-macrophage system?Blood levels of diminished interferon (INF) -and interleukin -8 ( IL-8 ) Pathogenesis?Susceptibili
9、ty of bacterial infection on CNS in the children?Specific immune?Immaturity of both the cellular and humoral immune systems?Insufficient antibody-mediated protection?Diminished immunologic response?Bacterial virulence Pathogenesis?A offending bacterium from blood invades the leptomeninges. ?Bacteria
10、l toxics and Inflammatory mediators are released.?Bacterial toxics?Lipopolysaccharide, LPS?Teichoic acid?Peptidoglycan ?Inflammatory mediators?Tumor necrosis factor, TNF?Interleukin-1, IL-1?Prostaglandin E2, PGE2Pathogenesis?Bacterial toxics and inflammatory mediators cause suppurative inflammation.
11、?Inflammatory infiltration?Vascular permeability alter?Tissue edema ?Blood-brain barrierdetroy?Thrombosis Pathology?Diffuse bacterial infections involve the leptomeninges, arachnoid membrane and superficial cortical structures, and brain parenchyma is also inflamed.?Meningeal exudate of varying thic
12、kness is found.?There is purulent material around veins and venous sinuses, over the convexity of the brain, in the depths of the sulci, within the basal cisterns, and around the cerebellum, and spinal cord may be encased in pus.?Ventriculitis (purulent material within the ventricles) has been obser
13、ved repeatedly in children who have died of their disease.Pathology?Invasion of the ventricular wall with perivascular collections of purulent material, loss of ependymal lining, and subependymal gliosis maybe noted. ?Subdural empyema may occur.?Hydrocephalus is an common complication of meningitis.
14、?Obstructive hydrocephalus ?Communicating hydrocephalusPathology?Blood vessel walls may infiltrated by inflammatory cells.?Endothelial cell injury?Vessel stenosis?Secondary ischemia and infarction?Ventricle dilatationwhich ensues may be associated with necrosis of cerebral tissue due to the inflamma
15、tory process itself or to occlusion of cerebral veins or arteries.Pathology?Inflammatory process may result in cerebral edema and damage of the cerebral cortex.?Conscious disturbance?Convulsion?Motor disturbance ?Sensory disturbance?Meningeal irritation sign is foundbecause the spinal nerve root is
16、irritated.?Cranial nerve may be damagedClinical manifestation?Bacterial meningitis may present acutely (symptoms evolving rapidly over 1-24 hours) in most cases.?Symptoms and signs of upper respiratory or gastrointestinal infection are found before several days when the clnical manifestations of bac
17、terial meningitis happen.?Some patients may access suddenly with shock and DIC.Clinical manifestation?Toxic symptom all over the body?Hyperpyrexia?Headache?Photophobia?Painful eye movement?Fatigued and weak ?Malaise, myalgia, anorexia, ?Vomiting, diarrhea and abdominal pain?Cutaneous rash?Petechiae,
18、 purpuraClinical manifestation?Clinical manifestation of CNS?Increased intracranial pressure?Headache?Projectile vomiting ?Hypertension ?Bradycardia ?Bulging fontanel ?Cranial sutures diastasis?Coma ?Decerebrate rigidity ?Cerebral herniaClinical manifestation?Clinical manifestation of CNS?Seizures?S
19、eizures occur in about 20%-30% of children with bacterial meningitis.?Seizures is often found in haemophilus influenzae and pneumococal infection.?Seizuresis correlative with the inflammation of brain parenchyma, cerbral infarction and electrolyte disturbances.第一课件网站Clinical manifestation?Clinical m
20、anifestation of CNS?Conscious disturbance?Drowsiness?Clouding of consciousness ?Coma?Psychiatric symptom?Irritation ?Dysphoria ?dullnessClinical manifestation?Clinical manifestation of CNS?Meningeal irritation sign?Neck stiffness?Positive Kernigs sign?Positive Brudzinskis signClinical manifestation?
21、Clinical manifestation of CNS?Transient or permanent paralysis of cranial nerves and limbs may be noted. ?Deafness or disturbances in vestibular function are relatively common.?Involvement of the optic nerve, with blindness, is rare. ?Paralysis of the 6thcranial nerve, usually transient, is noted fr
22、equently early in the course.Clinical manifestation?Symptom and signs of the infant under the age of 3 months?In some children, particularly young infants under the age of 3 months, symptom and signs of meningeal inflammation may be minimal.?Fever is generally present, but its absence or hypothermia
23、in a infant with meningeal inflammation is common. ?Only irritability, restlessness, dullness, vomiting, poor feeding, cyanosis, dyspnea, jaundice, seizures, shock and coma may be noted. ?Bulging fontanel may be found, but there is not meningeal irritation sign.Complication?Subdural effusion?Subdura
24、l effusions occur in about 10%-30% of children with bacterial meningitis.?Subdural effusions appear to be more frequent in the children under the age of 1 year and inhaemophilus influenzae and pneumococal infection.?Clinical manifestations are enlargement in head circumference, bulging fontanel, cra
25、nial sutures diastasis and abnormal transillumination of the skull.?Subdural effusions may be diagnosed by the examination of CT or MRI and subdural pricking.Complication?Ependymitis ?Neonate or infant with meningitis ?Gram-negative bacterial infection ?Clinical manifestation?Persistent hyperpyrexia
26、, ?Frequent convulsion ?Acute respiratory failure ?Bulging fontanel ?Ventriculomegaly (CT) ?Cerebrospinal fluidby ventricular puncture?WBC50109/L?Glucoseo.4g/LComplication?Cerebullar hyponatremia?Syndrem of inappropriate secretion of antidiuretic hormone (SIADH)?Hyponatremia ?Degrade of blood osmoti
27、c pressure?Aggravatedcerebral edema?Frequent convulsion ?Aggravated conscious disturbanceComplication?Hydrocephalus ?Increased intracranial pressure?Bulging fontanel?Augmentation of head circumference?Brain function disorder ?Other complication?Deafness or blindness?Epilepsy?Paralysis ?Mental retard
28、ation?Behavior disorderLaboratory Findings?Peripheral hemogram?Total WBC count ?20109/L 40109/L WBC?Decreased WBC count at severe infection?Leukocyte differential count?80%90% NeutrophilsLaboratory Findings?Rout examination of cerebrospinal fluid (CSF) ?Increased pressure of cerebrospinal fluid ?Clo
29、udiness?Evident Increased total WBC count (1000109/L)?Evident Increased neutrophils in leukocyte differential count?Evident Decreased glucose (1.1mmol/l)?Evident Increased protein level?Decreased or normal chloridate?CSF film preparation or cultivation : positive result Laboratory Findings?Especial
30、examination of CSF?Specific bacterial antigen test?Countercurrent immuno-electrophoresis?Latex agglutination?Immunofluorescent test?Neisseria meningitidis (meningococcus)?Haemophilus influenzae ?Streptococcus pneumoniae ( pneumococcus)?Group B streptococcusLaboratory Findings?Especial examination of
31、 CSF?Other test of CSF?LDH?Lactic acid?CRP?TNF and Ig?Neuron specific enolase (NSE)Laboratory Findings?Other bacterial test?Blood cultivation?Film preparation of skin petechiae and purpura?Secretion culture of local lesion ?Imageology examinationDiagnosis?Diagnostic methods?A careful evaluation of h
32、istory ?A careful evaluation of infants signs and symptoms?A careful evaluation of information on longitudinal changes in vital signs and laboratory indicators?Rout examination of cerebrospinal fluid (CSF)Differential diagnosis?Clinical manifestation of bacterial meningitis is similar to clinical ma
33、nifestation of viral, tuberculous , fungal and aseptic meningitis. ?Differentiation of these disorders depends upon careful examination of cerebrospinal fluid obtained by lumbar puncture and additional immunologic, roentgenographic, and isotope studies. Characteristics of CSF on common diseasein CNS
34、PM TM VW FM TE Pressure or Cloudiness or Pandy T or or ororWBC N L orL M Protein or or Glucos Chloridate or Cultivation Bacterium TB Viral Fungus TreatmentAntibiotic Therapy?Therapeutic principle?Good permeability for Blood-brain barrier ?Drug combination ?Intravenous drip ?Full dosage ?Full course
35、of treatmentAntibiotic Therapy?Selection of antibiotic?No Certainly Bacterium?Community-acquired bacterial infection?Nosocomial infection acquired in a hospital?Broad-spectrum antibiotic coverage as noted below?Children under age 3 months?Cefotaxime and ampicillin?Ceftriaxone and ampicillin (childre
36、n over age 1months)?Children over 3 months?Cefotaxime or Ceftriaxone or ampicillin and chloramphenicolAntibiotic Therapy?Certainly Bacterium?Once the pathogen has been identified and the antibiotic sensitivities determined, the most appropriate drugsshould selected.?N meningitidis : penicillin, tert
37、- cephalosporin?S pneumoniae: penicillin, tert- cephalosporin, vancomycin?H influenzae: ampicillin, tert- cephalosporin?S aureus: penicillin, nefcillin , vancomycin?E coli: ampicillin, chloramphenicol, tert- cephalosporinAntibiotic Therapy?Course of treatment?7 days for meningococcal infection?1014
38、days for H influenzae or S pneumoniae infection?More than 21 days for S aureus or E coli infection?1421 days for other organismsTreatmentGeneral and Supportive Measures?Monitor of vital sign?Correcting metabolic imbalances?Supplying sufficient heat quantity ?Correcting hypoglycemia?Correcting metabo
39、lic acidemia?Correcting fluids and electrolytes disorder?Application of cortical hormone?Lessening inflammatory reaction ?Lessening toxic symptom ?lessening cerebral edemaGeneral and Supportive Measures?Treatment of hyperpyrexia and seizures?Pyretolysis by physiotherapy and/or drug?Convulsive manage
40、ment ?Diazepam ?Phenobarbital ?Subhibernation therapy?Treatment of increased intracranial pressure?Dehydration therapy?20%Mannitol 5ml/kg vi q6h?Lasix 1-2mg/kg viGeneral and Supportive Measures?Treatment of septic shock and DIC?Volume expansion?Dopamine ?Corticosteroids ?Heparin ?Fresh frozen plasma
41、?Platelet transfusionsTreatmentComplication Measures?Subdural effusions ?Subduaral pricking?Draw-off effusions on one side is 20-30ml/time.?Once daily or every other day is requested. ?Time cell of pricking may be prolonged after 2 weeks.?Ependymitis?Ventricular puncture drainage?Pressure in ventricle be depressed.?Ventricular puncture may give ventricle an injection ofantibiotic.
