A 17-year-old female, a recent migrant from Southeast Asia, was admitted with an 8-day history of fever, rigors, headache and neck stiffness. On admission her temperature was 40°C, and Glasgow Coma Scale 15 with photophobia and marked neck stiffness. The chest radiograph was normal, and thick and thin films demonstrated no evidence of malaria.

An analysis of her cerebrospinal fluid (CSF) showed the following results:

Parameter

Patient Value

Adult Normal Range

Opening pressure

40 cm*

15 – 25

Glucose

0.8 mmol/L*

3.3 – 6.1

Protein

0.62 g/L*

0.1 – 0.5

Red Cell count

5 cells/high power field

0 – 5

White Cell Count

320 cells/high power field*

0 – 5

Neutrophils

70%

Lymphocytes

30%

Gram stain

Nil bacteria seen

a) List five likely infective organisms. (25% marks)

After a week of treatment with Ceftriaxone, her cultures were negative, and her clinical state remained static. A repeat CSF examination on day 4 showed the following results:

Parameter

Patient Value

Adult Normal Range

Opening pressure

41 cm*

15 – 25

Glucose

0.2 mmol/L*

3.3 – 6.1

Protein

1.5 g/L*

0.1 – 0.5

Red Cell count

0 cells/high power field

0 – 5

White Cell Count

560 cells/high power field*

0 – 5

Neutrophils

50%

Lymphocytes

50%

Gram stain

Nil bacteria seen

b) List five other CSF tests that would help determine the underlying diagnosis.

(20% marks)

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College answer

a)    List five likely infective organisms. 25% marks

  • Streptococcus pneumoniae,
  • Neisseria meningitides,
  • Haemophilus influenzae
  • Listeria
  • Mycobacteria

b)    List five other CSF tests that would help determine the underlying diagnosis. 20% marks

  • AFB and PCR for Tuberculous meningitis
  • Antigen/PCR for Cryptococcus
  • Antigen testing for syphilis
  • Fungal cultures
  • Cytology/flow cytometry

Discussion

What clues are present here, to suggest specific organisms?

  • Clearly bacterial meningitis by clinical features and CSF findings
  • Young patient (i.e. the possibility of paediatric organisms is not completely ruled out)
  • Sub-acute course (i.e. still not dead, suggesting a more indolent infectious process)
  • Normal level of consciousness (suggesting that there is no space-occupying lesion)

So, it could be something related to the patient's country of origin or it might be some standard Australian meningitis.  The list of possible bugs is therefore broad:

Common local organisms (representative of the developed world in general):

  • Streptococcus pneumoniae 
  • Listeria monocytogenes
  • Neisseria meningitidis
  • Haemophilus influenzae
  • Mycobacterium species

Southeast Asian organisms, according to Chong & Tan (2005), are totally different:

  • Klebsiella species
  • Staphylococcus species
  • Streptococcus agalactiae 
  • Salmonella
  • Acinetobacter 

b) so, whatever this is, it is resistant to ceftriaxone, and it does not Gram-stain. 

What could it be?

  • Mycobacteria:
    • M.tuberculosis
  • Fungi:
    • Cryptococcus neoformans
  • Viruses:
    • HSV
    • VZV
    • CMV
    • HIV
    • Enterovirus
  • Random:
    • Treponema pallidum
    • Borrelia burgdorferi (Lyme disease)

Additionally, one might wish to consider non-infectious causes, such as lymphoma, vasculitis, or drug-induced meningitis (eg. due to cotrimoxazole or azathiaprine).

Tests for this broad range of possibilities would have to include:

  • Cryptococcal antigen
  • Mycobacterial PCR
  • Syphilis PCR
  • HSV PCR
  • VZV PCR
  • India ink stain
  • Fungal cultures

References

References

Oh's Intensive Care manual: Chapter   54  (pp. 597)  Meningitis  and  encephalomyelitis by Angus  M  Kennedy

Beaman, Miles H. "Community‐acquired acute meningitis and encephalitis: a narrative review." Medical Journal Of Australia209.10 (2018): 449-454.

Lee, Bonita E., and H. Dele Davies. "Aseptic meningitis." Current opinion in infectious diseases 20.3 (2007): 272-277.

Beer, R., P. Lackner, and B. Pfausler. "Nosocomial ventriculitis and meningitis in neurocritical care patients." Journal of neurology 255.11 (2008): 1617-1624.

Korinek, A-M., et al. "Prevention of external ventricular drain–related ventriculitis." Acta neurochirurgica 147.1 (2005): 39-46.

NSW Health. Infants and children: acute management of bacterial meningitis: clinical practice guideline. North Sydney: NSW Ministry of Health; 2014.

Tunkel, Allan R., et al. "Practice guidelines for the management of bacterial meningitis." Clinical infectious diseases 39.9 (2004): 1267-1284.

Hearmon, Christine J., and Salil K. Ghosh. "Listeria monocytogenes meningitis in previously healthy adults." Postgraduate medical journal 65.760 (1989): 74-78.

Chong, H. T., and C. T. Tan. "Epidemiology of central nervous system infections in Asia, recent trends." Neurology Asia 10 (2005): 7-11.