Inflammations & infections of CNS and Cerebrospinal fluid

1. Inflammations & infections of CNS and Cerebrospinal fluid Dr Aarathi Rau

2. Infections of the CNS Meninges,brain,both • Meningitis- • Pachymeningitis:Epidural and subdural infections • Leptomeningitis-Subarachnoid • Brain- • Cerebral abscess-focal inflammation • Encephalitis-diffuse inflammation

4. Formation,circulation,function of CSF • Formation-500 ml/day • Ultrafilteration & secretion –choroid plexus, ependymal lining of ventricles • Circulation: ventricular system-foramina-subarachnoid space

5. Function of CSF • Protects, lubricates the brain • Provides nutrients, removes waste 90-150 ml adult 10-60 ml in newborn Blood brain barrier –homeostasis;electrolytes Urea,glucose ,protein,creatinine passively along concentration gradient

6. Normal CSF • Thin, colourless, clear fluid • Pressure 90-180mm WATER (10-100 neonates) • 0-5 WBC’s /mm3 (neonates 0-30/ mm3 ) • Lymphocytes & monocytes • Occasional ependymal or choroid plexus cells • Protein 15-45mg/dl • Glucose 50-80mg/dl • Chloride 113-130 mEq/L • Sterile

7. Meningitis Def: inflammatory process of the leptomeninges & CSF within the subarachnoid space • Meningoencephalitis =+inflammation of brain parenchyma • Classification • Acute • Aseptic • Chronic

8. Pyogenic meningitis pathogenesis • Blood borne • Direct-sinuses,mastoid,middle ear,dural venous sinuses,direct trauma,fracture skull • Neonates:E Coli,Strep pneumoniae, Adolescents: N Meningitides, H influenzae • Adults: N Meningitides, Strep pneumoniae type 3 • Elderly :Listeria monocytogenes,strep pneumoniae type 3

9. Clinical features • General • Headache,altered consciousness,vomiting • Neck stiffness

10. Gross • Pus in the subarachnoid space • Meningeal vessels engorged • Location-Pneumococcal-convexities • Tracks along vessels, ventriculitis • Microscopy • PMN in SA space,> meningial vessels • Thrombosis of superficial vessels & • Cerebral ischemic damage

12. CSF in Pyogenic Meningitis • Increased pressure • Purulent/cloudy • ↑protein • ↓ glucose • Leucocytosis • Neutrophils ++ • Gram stain • Culture

13. Sequele • Resolution • Cerebritis,hemorrhagic infarction of brain • Fibrosing meningitis • Hydrocephalus • Chronic adhesive arachnoiditis

14. (Aseptic)Lymphocytic meningitis • Viral usually (Coxsackie, EBV, ECHO) Less fulminant than bacterial • Usually recover • Few specimens • Mild lymphocytic infiltrate of the meninges

15. CSF in Viral meningitis Clear appearance Mild pleocytosis Lymphocytes + Protein↑ Glucose –WNL Culture sterile Virological exam-Coxsackie, EBV, ECHO

16. Tubercular meningitis • Hematogenic spread • Gross:Thickening & opacity of leptomeniges • Basal meningitis, encasing cranial N’s • Discrete white granules on the meninges +/- • Microscopy-granulomas, lympho-plasmacytic infiltrate • Obliterative endarteritis

17. Tubercular meningitis • Sequele-adhesive, fibrous, arachnoiditis, • Hydrocephalus • Infarction following endarteritis • Tuberculoma-intraparenchymal

18. CSF in Tubercular meningitis • Moderate pleocytosis • Lymphocytosis (early –neutrophilia) • Glucose ↓ (< pyogenic ) • Protein +++ • Cobweb appearance /clot • AFB, culture, PCR. • Atypical mycobacteria

19. Syphilis Meningovascular neurosyphilis:Chronic meningitis Base of brain Cerebral convexities+/-, Spinal leptomeninges Cerebral Gumma Microscopy-endarteritis obliterans (Heubner arteritis) with plasma cell cuffing

21. Cerebral abscess • Def: Focal inflammation of the parenchyma of the brain • Routes of infection • Secondary to meningitis • Local spread (middle ear,mastoid) • Hematogenous-BE,cyanotic heart disease,bronchiectasis • Trauma

22. GROSS MORPHOLOGY • Ill defined local swelling • preferred sites frontal lobe,parietal lobe cerebellum depending on aetiology • C/S fibrous capsule soft central liquefactive necrosis surrounding oedema

23. Morphology • Microscopy • Abscess containing necrosis surrounded by granulation tissue ,fibrosis & gliosis • Microbiology:mixed bacteria + anaerobes

24. Encephalitis • Diffuse brain inflammation • Causative org: viral,rickettsia,bacteria (listeria) • Death of neurons

25. HIV associated Neurologic disorders • Primary: • CNS • Primary HIV encephalopathies • Giant cell encephalitis, leucoencepalopathy, gray matter disease • Myelopathy • Lymphocytic Meningitis-seroconversion • PNS • Skeletal muscle myositis

26. HIV associated Neurologic disorders • Associated with immune supressed condition • Opportunistic infections • Lymphoma

27. CSF in AIDS • Aseptic HIV meningitis-lymphocytic meningitis • Infections • M. tuberculosis less reactive • Mycobacterium avium intracellulare • Cryptococci • Neurosyphilis • Malignancies

29. OTHER INFECTIONS • Prion disease (CJD) • Fungal infections • Parasitic infections malaria, toxoplasmosis,Echinococcus,cysticercosis

33. Intracranial hemorrhage • Intracerebral hematoma-associated with hypertension,(AV malformations,tumour ) • Subarachnoid hemorrhage • Any age group • Associated with rupture of Berry aneurysm

36. Traumatic Clear supernatant Clearing from tube 1 to 3 Fresh RBC’s Subarachnoid hemorrhage Xanthochromia>4 hrs upto 2-4 weeks Same appearance in 1,2 & 3 Crenated RBC’s Hemorrhagic tap

38. Lumbar puncture • Diagnostic • Meningitis;bacterial,TB,fungal, viral *,syphilis • encephalitis • Guillain Barre Syndrome • Matastasis lymphoma,leukaemia,breast,lung Haemorrhage • Any disorder affecting the nervous system! • Therapeutic • Administer dye for imaging studies • Administer medications eg CT,anaesthesia

41. Processing • Method of collection • 3 sterile bottles • Biochemistry & immunology-blood glucose • Microbiology • Cell count,cytology • Send QUICKLY