A 31-year-old male with no significant past medical history presents with a fever of 39C and a bifrontal throbbing headache with photosensitivity for 1 day. He has also had nausea and 3 episodes of non-bloody, non-bilious emesis. He denies recent trauma, rash, recent travel, and sick contacts. There is no altered mental status.
On physical exam, he has photophobia but no neurological deficits. He complains of a stiff neck but has negative Kernig and Brudzinski signs. He has normal heart, lung, and abdominal exams.
What’s on the top of your differential diagnoses?
Meningitis!
It’s important to not delay meningitis workup and treatment because without treatment, the case fatality rate can be as high as 70% for bacterial meningitis1. Delays in treatment increase adverse events, including in-hospital mortality and neurological deficits at discharge2,3.
There are a few questions that seem to come up each time we think about the diagnosis and treatment of meningitis:
1. When should you get a CT head before performing the lumbar puncture?
The Infectious Diseases Society of America (IDSA) recommends that only the following patients should get a CT head before their LP4:
Immunocompromised state (i.e. HIV, immunosuppressive therapy, transplants)
History of CNS disease (mass lesion, stroke, or focal infection)
New-onset seizure (within 1 week of presentation)
Papilledema*
Abnormal Level of Consciousness
Focal Neurological Deficit
*Using ultrasound to measure papilledema:
To evaluate for increased ICP on ultrasound, measure the optic nerve sheath diameter (ONSD) 3mm distal from the posterior globe (Image 1)5. ONSD > 5mm is indicative of increased ICP. Optic disc swelling is shown in Image 2 along with an enlarged ONSD6.
2. Should you give steroids?
A 2015 Cochrane Meta-Analysis6 provides guidance on this topic. This meta-analysis had 4121 individual patients for 25 randomized trials. 22 studies used dexamethasone and the remaining 3 studies used hydrocortisone or prednisone. The meta-analysis found no difference in overall mortality between patients who received dexamethasone and those who didn’t.
However, in the subgroup analysis, glucocorticoids reduced mortality in patients with meningitis caused by S. pneumoniae (NNT 18). Glucocorticoids were also associated with lower rates of hearing loss (NNT 21) and short-term neurological sequelae. Side effects of dexamethasone were minimum, with a small increase in recurrent fever (NNH 16) but no adverse outcomes7,8.
Take home points:
1. Don’t delay workup and treatment for meningitis.
2. Not everyone needs a CT Head before LP - refer to the IDSA guidelines.
3. Start antibiotics as early as possible, and before the CT Head/LP if they are going to take >1 hour.
4. Give glucocorticoids early - before or with antibiotics.
Samita Heslin is a current first year resident at Stony Brook Emergency Medicine.
@SamitaHeslin
References:
“Chapter 2: Epidemiology of Meningitis Caused by Neisseria Meningitidis, Streptococcus Pneumoniae, and Haemophilus Influenza Format:Select One PDF [95K].” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 15 Mar 2012, www.cdc.gov/meningitis/lab-manual/chpt02-epi.html.
Steven, Peduzzi, & Quagliarello. "Community-acquired bacterial meningitis: risk stratification for adverse clinical outcome and effect of antibiotic timing." Ann Intern Med 129.11_Part_1 (1998): 862-869.
Auburtin, Marc, et al. "Detrimental role of delayed antibiotic administration and penicillin-nonsusceptible strains in adult intensive care unit patients with pneumococcal meningitis: the PNEUMOREA prospective multicenter study." Critical care medicine 34.11 (2006): 2758-2765.
Tunkel, Allan, et al. "Practice guidelines for the management of bacterial meningitis." Clin Infect Dis 39.9 (2004): 1267-1284.
“Keeping an Eye on Intracranial Pressure: Measuring ICP Using Ocular Ultrasound.” UK EMIG QuickHit, 12 Dec. 2012, ukemigquickhit.wordpress.com/2012/10/15/keeping-an-eye-on-intracranial-pressure-measuring-icp-using-ocular-ultrasound/.
“Papilledema and the Crescent Sign.” SinaiEM, 13 Dec. 2012, sinaiem.org/papilledema-and-the-crescent-sign/.
Brouwer, Matthijs, et al. "Corticosteroids for bacterial meningitis." Cochrane Database of Systematic Reviews (2015). https://www.cochrane.org/CD004405/ARI_corticosteroids-bacterial-meningitis
Mount, Hillary, and Boyle. "Aseptic and Bacterial Meningitis: Evaluation, Treatment, and Prevention." Am Fam Physician 96.5 (2017).