1. Meningitis Risk factors:
Head injury – skull #, cranial or spine surgery
Causes: Septic site – pneumonia, mastoiditis, sinusitis, OM
1. Viral Immunosuppressed – CA, AIDS, hyposplenism, sickle-cell dz,
Commonest cause hypogammaglobinaemia
Usually benign and self-limiting Host factor – complement or antibody deficiency
Complete recovery w/o specific Rx is the norm. Foreign body – CSF shunt/ VP shunt (prone to staph. Meningitis)
Common organisms: echoviruses, mumps. Less commonly
HSV & zoster, coxsackie Causes of bacterial meningitis by population groups:
Neonate 1. Group B strep
2. Bacterial – high mortality & morbidity 2. Gram negative bacilli (E coli, proteus)
3. Fungal 3. Listeria monocytogenes
4. Others – malignancies, drugs (NSAIDS, trimethoprim), intrathecal Pre-school 1. H. influenzae
drugs, sarcoidosis, SLE 2. N. meningitides
child
3. Strep. Pneumoniae
4. M. TB
DDx: Older child / 1. N. Meningitidis
1. Any acute infections eg malaria Adults 2. Strep. Pneumoniae
2. Local infections causing neck stiffness 3. M. TB
4. L. monocytogenes
3. Encephalitis 5. H. influenzae
4. Subarachnoid hemorrhage Elderly / DM/ 1. Strep. Pneumoniae
2. N. Meningitidis
debilitated
S/S: 3. H. influenzae
4. L. monocytogenes
Meningism Headache Kernig’s sign 5. M. TB
Photophobia Brudzinski’s sign (hip Immuno- 1. Strep. Pneumoniae
Neck stiffness flexion on flexion of neck) compromised 2. N. Meningitidis
Opisthotonus 3. H. influenzae
4. L. monocytogenes
↑ ICP Headache Fits 5. C. Neoformans
Vomiting Cushing’s reflex: ↑BP & 6. Toxoplasma gondii
Irritability ↓pulse 7. S. aureus
Drowsiness Irregular respiration Meningococcus: Spread by air-borne route. May result in meningococcaemia.
↓consciousness/coma Papilloedema ∼ Cxs of meningococcaemia: meningitis, purpuric rash, shock,
Focal neuro signs DIVC, renal failure, peripheral gangrene, arthritis (rxtive or septic),
pericarditis (rxtive or septic)
Septicaemia Malaise DIC H. influenzae: a/w ottitis media
Fever ↓BP, ↑pulse, tachypnoea Pneumococcus: a/w ottitis media and pneumonia, esp in elderly, alcoholics &
Rash – petechiae/purpura Arthritis immunocompromised.
suggests meningiococcus. Odd behaviour TB: chronic or acute on chronic, a/w chronic headache, isolated CN6 palsy
due to ↑ICP, and S/S of TB eg fever, nightsweats.
2. Viral
Investigations: Supportive treatment
CT head Exclude ↑ICP (eg cerebral abscess, head injury, brain tumour) Completer recovery without specific therapy is the norm.
pre-LP.
LP Exclude ↑ ICP by CT head, fundoscopy & clinical signs. Bacterial
Tubes IV penicillin stat on suspicion of bacterial meningitis
1. Cell count, cytospin for cell and differential count
2. Protein & glucose Modify ABx regimen according to CSF invx results
3. Microbiology – gram stain, C&S, AFB smear, TB culture, Meningococcal Benzyl penicillin (2.4g/4hr slow IV)
Indian ink stain, fungal culture Pneumococcal Ceftriaxone (2g/12 hrly IV)
4. Cryptococcal antigen, bacterial antigens (S. pneumonia, N. H. influenzae Ceftriaxone
meningitides, H. influenzae, GBS) GBS/ Gram negative bacilli Ceftriaxone + Gentamicin + ampicillin
FBC (50mg/kg/6 hr IV)
L. monocytogenes Gentamicin + ampicillin
U/E/Cr M TB Pyrazinamide, isoniazid, rifampicin, ethambutol
DIVC screen Especially if meningococcaemia is suspected. 6-12 mths
Blood glucose To compare with CSF C. neoformans Amphotericin + flucytosine
Blood C/S
Urine C/S Treatment for pyogenic meningitis of unknown cause
Neonate Ampicillin + Ceftriaxone or gentamicin
CXR ?Lung abscess Infant Ampicillin + Ceftriaxone
Pre-school child Ceftriaxone
Typical CSF in meningitis Older child / adults Penicillin G (400K units/kg/day) + Ceftriaxone
Pyogenic TB Viral (‘aseptic’) Elderly (>50YO) Ampicillin + Ceftriaxone
Appearance Turbid Fibrin web forms Clear Prophylaxis for close contacts--meningococcus:
on standing ∼ Children: 2 days of oral rifampicin (3-12mths 5mg/kg 12 hrly;
Predominant cell Neutrophils Lymphocytes Lymphocytes >1yr 10 mg/kg 12 hrly)
Cell count/ mm3 90-1000+ 10-1000 50-1000 ∼ Adults: single dose of 500mg ciprofloxacin OR rifampicin
Glucose ↓ (< 1/2 plasma) ↓ (< 1/2 plasma) N (> 1/2 plasma) 600mg 12 hrly for 2 days.
Vaccination: available for groups A & C meningococci, but not group B.
Protein (g/L) ↑ (>1.5) ↑ (1-5) N (<1)
Culture / smear Positive Usually not seen Negative
Complications of bacterial meningitis:
1) Hydrocephalus: pus causes adhesions which cause CSF flow
Treatment:
obstruction. Rx: ±surgical drainage
Monitoring: BP, pulse, RR, temp, SpO2, conscious level
2) Cranial nerve damage
Supplemental O2
3) Secondary cerebral infarction: due to obliterative endarteritis of the
ABx if bacterial (see below)
leptomeningeal arteries passing through the meningeal exudates.
Antipyretics and antiemetics
4) Cerebral venous sinus thrombosis
Corticosteroids for ↑ICP (controversial): 0.15mg/kg dexamethasone
Digitally signed by DR WANA HLA SHWE
DN: cn=DR WANA HLA SHWE, c=MY, o=UCSI
University, School of Medicine, KT-Campus,
Terengganu, ou=Internal Medicine Group,
email=wunna.hlashwe@gmail.com
Reason: This document is for UCSI year 4 students.
Date: 2009.02.24 14:18:24 +08'00'