A 27-year-old male with a prolonged ICU stay following a subarachnoid haemorrhage has a CSF specimen taken from his external ventricular drain (EVD).

The CSF gram stain result is shown below:

Parameter

Patient Value

Adult Normal Range

Red Blood Cells

1946 x 106/L*

0 – 5

Polymorphs

198 x 106/L*

0 – 5

Mononuclear cells

74 x 106/L*

0 – 5

Gram stain:

Scant gram-positive cocci.

a) What is your assessment of the CSF result and provide a reason? (10% marks)

b) List two likely organisms commonly reported on the Gram stain in this setting.

(10% marks)

c) List two therapies you may consider based on this report. (10% marks)

[Click here to toggle visibility of the answers]

College answer

a)    What is your assessment of the CSF result and provide a reason? 10% marks
Ventriculitis: due to raised WCC:RCC ratio and a positive gram stain

b)    List two likely organisms commonly reported on the Gram stain in this setting. 10% marks
Staphylococcus epidermidis Staphylococcus aureus

c)    List 2 therapies you may consider based on this report. 10% marks
Removal of EVD / replacement

Vancomycin
 

Discussion

After the candidate has reestablished heir composure from the grammatic assault of "What is your assessment and provide a reason", they would immediately reach the conclusion that this patient has an infected EVD. Allocating 10% of the mark to this question seems generous. The CSF is clearly infected, with a raised WCC:RCC ratio and organisms on the Gram stain. 

Possible organisms are  Staphylococcus aureus, Staphylococcus epidermidis or Streptococcus pyogenes.

Apart from removing the infected catheter, one would have to consider some antibiotics, which in the context of unknown sensitivities should consist of cephalosomething and vancomycin.

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.