{"id":5344,"date":"2011-03-26T00:33:49","date_gmt":"2011-03-26T04:33:49","guid":{"rendered":"http:\/\/insidesurgery.com\/?p=5344"},"modified":"2013-05-27T12:57:52","modified_gmt":"2013-05-27T16:57:52","slug":"bacterial-meningitis","status":"publish","type":"post","link":"https:\/\/insidesurgery.com\/2011\/03\/bacterial-meningitis\/","title":{"rendered":"Bacterial Meningitis"},"content":{"rendered":"
Pathophysiology<\/strong><\/p>\n 1)<\/strong> acute suppurative infection within the subarachnoid space 2)<\/strong> common entry site is via nasopharynx<\/p>\n <\/p>\n Signs and Symptoms<\/strong><\/p>\n acute onset of<\/em> – 1)<\/strong> fever 2)<\/strong> headache 3)<\/strong> lethargy 4)<\/strong> stiff neck 5)<\/strong> seizures 6)<\/strong> stroke 7)<\/strong> nausea 8)<\/strong> vomiting 9)<\/strong> photophobia 10)<\/strong> increased intracranial pressure 11)<\/strong> positive Kernig’s sign 12)<\/strong> positive Brudzinski’s sign 13)<\/strong> subacute – presentation over several days 14)<\/strong> if cause is meningococcemia, diffuse rash that rapidly turns petechial<\/p>\n Characteristic Test Findings<\/strong><\/p>\n Laboratory<\/em> – CSF on lumbar puncture – 1)<\/strong> cell count 1,000-10,000 (mostly neutrophils) 2)<\/strong> protein elevated in relation to cell count 3)<\/strong> glucose 40% of normal 4)<\/strong> increased cytokines 5)<\/strong> increased chemokines 6)<\/strong> increased intracranial pressure (>180 mm H2O) 7)<\/strong> if cause is Neisseria meningitidis – positive Schwartzman’s reaction<\/p>\n Histology\/Gross Pathology<\/strong><\/p>\n 1)<\/strong> inflammation of meninges 2) cerebral edema<\/p>\n Associated Conditions<\/strong><\/p>\n 1)<\/strong> pneumococcal pneumonia (predisposes to Streptococcus pneumonia<\/em>) 2)<\/strong> otitis media 3)<\/strong> alcoholism 4)<\/strong> diabetes 5)<\/strong> splenectomy 6)<\/strong> complement deficiency (predisposes to N. meningitides<\/em> infection) 7)<\/strong> hypogammaglobulinemia<\/p>\n Biochemistry<\/strong><\/p>\n 1)<\/strong> loss of cerebral blood flow autoregulation 2)<\/strong> N. meningitidis<\/em> releases endotoxin before cell lysis.<\/p>\n Inheritance\/Epidemiology<\/strong><\/p>\n 1)<\/strong> highest prevalence in infants 6-12 months of age 2)<\/strong> most common organisms in infants – S. pneumoniae<\/em> (50%), N. meningitides<\/em> (25%), group B strep (25%), and Listeria<\/em> (10%) 3)<\/strong> most common in elderly is S. pneumoniae 4)<\/strong> most common in young adults is N. meningitidis (meningiococcus) 5)<\/strong> most common used to be Haemophilus influenzae but has greatly decreased in incidence since 1987 introduction of vaccine 6)<\/strong> overall incidence is 2.5\/100,000 7)<\/strong> Listeria affects mostly elderly and transplant patients<\/p>\n Treatment<\/strong><\/p>\n 1)<\/strong> ceftriaxone 2)<\/strong> vancomycin 3)<\/strong> ampicillin (for Listeria) 4)<\/strong> penicillin (for Neisseria) 5)<\/strong> cephalosporin if hospital acquired and Pseudomonas likely 6)<\/strong> vaccination against some specific capsular groups in meningiococcus cases possible 7)<\/strong> chemoprophylaxis with monocycline eradicates carrier state in meningiococcus 8)<\/strong> aim is to reduce personal contacts with affected individuals 9)<\/strong> repeat lumbar puncture in 48 h to make sure sterilization has occurred<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" Pathophysiology 1) acute suppurative infection within the subarachnoid space 2) common entry site is via nasopharynx<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[5123],"tags":[4234,5243,4233,5242,5241,4235],"yoast_head":"\n