Cerebrospinal fluid (CSF) lactate for distinguishing acute bacterial meningitis from acute viral meningitis in adults

Date First Published:
April 24, 2018
Last Updated:
July 25, 2018
Report by:
Alexander Zozula, Resident Physician (Stanford University Department of Emergency Medicine)
Search checked by:
Christopher Stave, Stanford University Department of Emergency Medicine
Three-Part Question:
In [adults undergoing lumbar punctures for possible meningitis] what are [the sensitivity and specificity of CSF lactate] for [diagnosing acute community-acquired bacterial meningitis]?
Clinical Scenario:
You are evaluating a patient in the emergency department in whom you are considering the diagnosis of acute community-acquired bacterial meningitis. You perform a lumbar puncture and when ordering CSF studies wonder if sending a CSF lactate would help distinguish acute bacterial meningitis (ABM) from acute viral meningitis (AVM).
Search Strategy:
PubMed
((("bacteria"[mesh] OR "bacterial infections"[mesh]) AND ("meningitis"[mesh:noexp])) OR "meningitis, bacterial"[mesh] OR (mening*[tw] AND (bacteria*[tw] OR escherichia[tw] OR haemophilus[tw] OR listeria[tw] OR meningococc*[tw] OR neisseria[tw] OR pneumococc*[tw] OR streptococc*[tw]))
AND (“cerebrospinal fluid”[mesh] OR “cerebrospinal fluid”[subheading] OR “cerebrospinal fluid”[tw] OR “CSF”[tw]) AND (“lactates”[mesh] OR lacta*[tw] OR lacti*[tw]))
AND english[lang]

EMBASE
(((‘bacterium’/exp OR ‘bacterial infection’/exp) AND ‘meningitis’/exp) OR (mening*:ab,ti,kw AND (bacteria*:ab,ti,kw OR ‘escherichia’:ab,ti,kw OR ‘haemophilus’:ab,ti,kw OR listeria:ab,ti,kw OR meningococc*:ab,ti,kw OR ‘neisseria’:ab,ti,kw OR pneumococc*:ab,ti,kw OR streptococc*:ab,ti,kw)))
AND ((‘cerebrospinal fluid'/exp OR ‘cerebrospinal fluid’:ab,ti,kw OR ‘CSF’:ab,ti,kw) AND (‘lactic acid'/exp OR lact*:ab,ti,kw))
AND [english]/lim
Outcome:
PubMed -- 506 results
EMBASE -- 643 results
Total -- 742 unique results

106 full text articles were reviewed after screening titles/abstracts from which 33 original articles and two systematic reviews were ultimately selected for inclusion. One of the 33 articles (Schwarz et al.) was initially screened out but ultimately included after reviewing the two systematic reviews and the full text of the article. For completeness, the original articles included in the two systematic reviews are listed below as there appear to be several minor discrepancies in the data abstracted in the systematic reviews.
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
CSF lactate level: a useful diagnostic tool to differentiate acute bacterial and viral meningitis. Abro et al. 2009 UAE Single hospital
Mean 34±12y, 84% male
n=53 ABM, n=42 AVM
Cohort
Lactate cutoff 3.8mM
Sensitivity 98.10% Excluded ABM without organism identified
Significant overlap in patients with Abro et al. 2008
Specificity 100%
LR+ Infinity
LR- 0.019
Cerebrospinal fluid analysis: acute bacterial versus viral meningitis Abro et al. 2008 UAE Single hospital
Mean 34±12y, 87% male
n=86 ABM, n=48 AVM
Cohort
Lactate cutoff 3.8mM
Sensitivity 98.8% (?erroneously reported as 98.3% by authors) Significant overlap in patients with Abro et al. 2009
Specificity 100%
LR+ Infinity
LR- 0.012
Cerebrospinal fluid lactate in the diagnosis of meningitis. Diagnostic value compared to standard biochemical methods. Berg et al. 1982 Sweden Multicenter
Mean 30 vs. 21y ABM vs. AVM
n=18 ABM, n=121 AVM
Cohort
Lactate cutoff 3.0mM
Sensitivity 88.90% Excluded ABM without organism identified
Specificity 92.60%
LR+ 12
LR- 0.12
Comparison between cerebrospinal fluid concentrations of glucose, total protein, chloride, lactate, and total amino acids for the differential diagnosis of patients with meningitis. Briem et al. 1983 Sweden Single hospital
Mean 44 vs. 29y ABM vs. AVM, 52% male
n=45 ABM, n=102 AVM
Cohort
Lactate cutoff 3.5mM
Sensitivity 100% Excluded ABM without organism identified
Specificity 96.10%
LR+ 25.5
LR-
Measurement of lactic acid in cerebrospinal fluid of patients with infections of the central nervous system. Brook et al. 1978 USA Single hospital
54% adults
n=25 ABM, n=26 AVM
Cohort
Lactate cutoff 3.9mM using chromatographic method
Sensitivity 100% Excluded ABM without organism identified
Specificity 100%
LR+ Infinity
LR-
Cerebrospinal fluid lactate as a marker to differentiate between community-acquired acute bacterial meningitis and aseptic meningitis/encephalitis in adults: a Danish prospective observational cohort Buch et al. 2018 Denmark Multicenter
Median 64 vs. 41y ABM vs. AVM, 51% male
n=51 ABM, n=125 AVM
Cohort
Lactate cutoff 3.5/4.5mM using Radiometer analyzer
Sensitivity 96.1%/92.2%
Specificity 84.8%/94.4%
LR+ 6.32/16.5
LR- 0.046/0.083
The clinical diagnostic significance of cerebrospinal fluid d-lactate for bacterial meningitis Chen et al. 2012 China Single hospital
Mean 43±15 vs. 32±17y, 45% vs. 67% male ABM vs. AVM
n=21 ABM, n=30 AVM
Cohort
Lactate cutoff 3.3mM
Sensitivity 71.40% Included patients pretreated with antibiotics/steroids
Specificity 100%
LR+ Infinity
LR- 0.286
Cerebrospinal fluid lactate and the diagnosis of meningitis. Curtis et al. 1981 UK Two hospitals
Unknown demographics
n=10 ABM, n=12 AVM
Cohort
Lactate cutoff 2.8mM
Sensitivity 100% Excluded ABM without organism identified
Specificity 100%
LR+ Infinity
LR-
Lactic-acid concentration in cerebrospinal fluid and differential diagnosis of meningitis. D'Souza et al. 1978 UK Two hospitals
Unknown demographics
n=5 ABM, n=26 AVM
Cohort
Lactate cutoff 4.3mM
Sensitivity 100% Unclear definition of ABM
Specificity 100%
LR+ Infinity
LR-
Cerebrospinal fluid lactic acid: a valuable aid in the of diagnosis septic meningitis. Ellis and Oei 1979 USA Single hospital
Unknown demographics
n=10 ABM, n=12 "CNS inflammation" including AVM
Cohort
Lactate cutoff 5.0mM
Sensitivity 100% Excluded ABM without organism identified
"CNS inflammation" group included not only AVM but also leukemia, ICH, MS, and "hypoxic seizures"
Specificity 100%
LR+ Infinity
LR-
Gas liquid chromatography in the rapid diagnosis of meningitis. Ferguson and Tearle 1977 UK Single hospital
Unknown demographics
n=8 ABM, n=15 AVM
Cohort
Lactate cutoff 5.6mM using chromatographic method
Sensitivity 100% Unclear definition of ABM
Included patients pretreated with antibiotics
Specificity 100%
LR+ Infinity
LR-
Rapid diagnosis of meningitis with use of selected clinical data and gas-liquid chromatographic determination of lactate concentration in cerebrospinal fluid. Gastrin et al. 1979 Sweden Single hospital
Median 33 vs. 54 vs. 24y ABM vs. presumed ABM vs. AVM
n=38 ABM, n=5 presumed ABM, n=17 AVM
Cohort
Lactate cutoff 3.5mM using chromatographic method
Sensitivity 96% Included patients pretreated with antibiotics
Specificity 82.40%
LR+ 5.4
LR- 0.056
Cerebrospinal fluid lactate in 78 cases of adult meningitis. Genton and Berger 1990 Switzerland Single hospital
Median 35/33y M/F, 46% male
n=25 ABM, n=28 AVM
Cohort
Lactate cutoff 4.2 using Hoffman-La Roche analyzer
Sensitivity 96% Included patients pretreated with antibiotics
Excluded ABM without organism identified
Specificity 96.4% (erroneously reported as 100% by authors)
LR+ 26.9
LR- 0.041
CSF lactate for accurate diagnosis of community-acquired bacterial meningitis Giulieri et al. 2015 Switzerland Multicenter
Median 53 vs. 35y, 50% vs. 56% male ABM vs. AVM
n=18 ABM, n=27 AVM
Cohort
Lactate cutoff 3.5mM
Sensitivity 100% Excluded ABM without organism identified
Excluded AVM without organism identified
Specificity 100%
LR+ Infinity
LR-
The use of cerebrospinal fluid lactate determination in the diagnosis of meningitis. Gould et al. 1980 UK Single hospital
Unknown demographics
n=6 ABM, n=26 AVM
Cohort
Lactate cutoff 3.4mM using chromatographic method
Sensitivity 83.30% ABM group included TB meningitis
Specificity 100%
LR+ Infinity
LR- 0.167
Lactic acid in cerebrospinal fluid: evaluation and application of an automated enzymatic assay. Herold et al. 1981 USA Single hospital
Unknown demographics
n=9 ABM, n=2 AVM
Cohort
Lactate cutoff 9mM
Sensitivity 100% Unclear definition of ABM
n=2 AVM makes the specificity extraordinarily fragile
Specificity 100%
LR+ Infinity
LR-
Use of cerebrospinal fluid lactate levels in the diagnosis of bacterial meningitis. Hurd et al. 1978 USA Single affiliated adult/children hospital
77% adult
n=11 ABM, n=80 comparator group including AVM
Cohort
Lactate cutoff 3.4mM using chromatographic method
Sensitivity 100% Excluded ABM without organism identified
Comparator group included not only AVM but also ICH, cancer, and post-neurosurgical patients
Specificity 97.50%
LR+ 40
LR-
CSF lactate in diseases of the CNS. Jordan et al. 1983 USA Single hospital
Unknown demographics
n=7 ABM, n=3 AVM
Cohort
Lactate cutoff 3.0mM
Sensitivity 100% Excluded ABM without organism identified
n=3 AVM makes the specificity extraordinarily fragile
Specificity 66.70%
LR+ 3
LR-
New and old diagnostic markers of meningitis in cerebrospinal fluid (CSF). Kleine et al. 2003 Germany Single hospital
Mean 49.5 vs. 43.1y, 58% vs. 54% male ABM vs. AVM
n=40 ABM, n=46 AVM
Cohort
Lactate cutoff 3.5mM
Sensitivity 100% Excluded ABM without organism identified
Specificity 100% (?erroneously reported as 99.6% by authors)
LR+ Infinity
LR-
Cerebrospinal fluid lactic acid in diagnosis of meningitis. Komorowski et al. 1978 USA Single hospital
Unknown demographics
n=21 "CNS infections", n=3 AVM
Cohort
Lactate cutoff 3.4mM using chromatographic method
Sensitivity 100% Unclear definition of ABM
"CNS infections" included not only ABM but also fungal meningitis and CNS syphilis
n=3 AVM makes the specificity extraordinarily fragile
Specificity 100%
LR+ Infinity
LR-
Comparison of cerebrospinal fluid C-reactive protein and lactate for diagnosis of meningitis. Komorowski et al. 1986 USA Single hospital
Unknown demographics
n=28 ABM, n=5 AVM
Cohort
Lactate cutoff 3.0mM
Sensitivity 100% Excluded ABM without organism identified
Specificity 100%
LR+ Infinity
LR-
Proposal for a New Score-Based Approach To Improve Efficiency of Diagnostic Laboratory Workflow for Acute Bacterial Meningitis in Adults Lagi et al. 2016 Italy Single ED
51% male
n=24 ABM, n=641 comparator group including AVM
Cohort
Lactate cutoff 3.9mM
Sensitivity 100% Data not published -- personal communication from author
Excluded ABM without organism identified and cases with organisms thought to represent contamination
Comparator group included not only AVM but all patients undergoing lumbar puncture to evaluate for meningitis and ultimately deemed to not have ABM
Specificity 97%
LR+ 33.7
LR-
Chemical analyses for early differential diagnosis between bacterial and viral meningitis. Landaas and Von Der Lippe 1985 Norway Single hospital
47% vs. 52% male ABM vs. AVM
n=19 ABM, n=24 AVM
Cohort
Lactate cutoff 6.0mM
Sensitivity 84.20% Included patients pretreated with antibiotics
Excluded ABM without organism identified
Specificity 100%
LR+ Infinity
LR- 0.158
Evaluation of cerebrospinal fluid lactic acid levels as an aid in differential diagnosis of bacterial and viral meningitis in adults. Lannigan et al. 1980 Canada Single hospital
58% male
n=14 ABM, n=14 AVM
Cohort
Lactate cutoff 3.9mM
Sensitivity 92.90% Excluded ABM without organism identified
Specificity 78.60%
LR+ 4.33
LR- 0.091
Lactic-acid concentration in cerebrospinal fluid and differential diagnosis of meningitis. Lauwers 1978 Belgium Single hospital
Unknown demographics
n=35 ABM, n=20 AVM
Cohort
Lactate cutoff 3.9mM using chromatographic method
Sensitivity 100% Excluded ABM without organism identified
Specificity 100%
LR+ Infinity
LR-
Value of CSF lactate in the differential diagnosis between bacterial meningitis and other diseases with meningeal involvement. Lester et al. 1985 Denmark Multicenter
Unknown demographics
n=16 ABM, n=15 AVM
Cohort
Lactate cutoff 3.5mM
Sensitivity 93.80% Included patients pretreated with antibiotics
Specificity 86.70%
LR+ 7.03
LR- 0.072
Value of cerebrospinal fluid analysis in the differential diagnosis of meningitis: a study in 710 patients with suspected central nervous system infection. Lindquist et al. 1988 Sweden Multicenter
Unknown demographics
n=63 ABM, n=616 comparator group including AVM
Cohort
Lactate cutoff 3.5mM
Sensitivity 88.90% ABM group included TB meningitis
Comparator group included not only AVM but also "unclassified meningitis", other infectious CNS conditions, seizures, and strokes
Specificity 96.40%
LR+ 24.9
LR- 0.115
How useful is cerebrospinal fluid lactate estimation in differential diagnosis of meningitis? Mandal et al. 1983 UK Single hospital
Unknown demographics
n=20 ABM, n=59 AVM
Cohort
Lactate cutoff 4.3mM
Sensitivity 100%
Specificity 98.30%
LR+ 59
LR-
Handheld Point-of-Care Cerebrospinal Fluid Lactate Testing Predicts Bacterial Meningitis in Uganda Patterson et al. 2013 Uganda Single hospital
Mean 31±13y, 50% male, 81% HIV+
n=17 ABM, n=128 comparator group including AVM
Cohort
Lactate cutoff 7.7mM using Accutrend POC analyzer
Sensitivity 88.20% Comparator group included not only AVM but also fungal and TB meningitis
Specificity 89.80%
LR+ 8.69
LR- 0.131
The differential diagnosis of bacterial and aseptic meningitis using cerebrospinal fluid laboratory tests. Ponka et al. 1983 Finland Single hospital
Unknown demographics
n=11 ABM, n=27 AVM
Cohort
Lactate cutoff 3.0mM
Sensitivity 90.90% Excluded ABM without organism identified
Specificity 96.30%
LR+ 24.5
LR- 0.094
Serum procalcitonin levels in bacterial and abacterial meningitis. Schwarz et al. 2000 Germany Single hospital
Mean 52y, 43% male
n=16 ABM, n=14 AVM
Cohort
Lactate cutoff 2.1mM using unknown method
Sensitivity 93.80% No mention of lactate assay method (main focus of study was procalcitonin)
Used lower cutoff of 2.1mM based on normal reference range
Specificity 42.90%
LR+ 1.64
LR- 0.146
Meningitis in adult patients with a negative direct cerebrospinal fluid examination: value of cytochemical markers for differential diagnosis Viallon et al. 2011 France Single ED
Mean 55±20 vs. 35±18y, 48% vs. 53% male ABM vs. AVM
n=35 ABM, n=218 AVM
Cohort
Lactate cutoff 3.8mM using i-STAT POC analyzer
Sensitivity 94.30% Excluded ABM with initially positive gram stain/antigen detection
Excluded ABM with concurrent alternative infection (e.g. pneumonia)
Excluded culture-negative ABM
Specificity 96.80%
LR+ 29.4
LR- 0.059
Quantitation of cerebrospinal fluid lactic acid in infectious and non-infectious neurological diseases de Almeida et al. 2009 Brazil Single hospital
Mean 21±20y, 53% male
n=20 ABM, n=41 AVM
Cohort
Lactate cutoff 3.5mM using Date Behring analyzer
Sensitivity 80%
Specificity 97.60%
LR+ 32.8
LR- 0.205
Cerebrospinal fluid lactate concentration to distinguish bacterial from aseptic meningitis: a systemic review and meta-analysis Huy et al. 2010 25 studies included (both adults and children)
n=783 ABM, n=909 AVM
Systematic review and meta-analysis AUC CSF lactate 0.984 Excluded non-English studies
No gray literature
Excluded studies with n<8 for either ABM or AVM
Excluded studies with comparator groups including but not exclusively comprised of AVM
AUC CSF WBC 0.948
AUC CSF glucose 0.881
AUC CSF/plasma glucose 0.952
AUC CSF protein 0.862
Diagnostic accuracy of cerebrospinal fluid lactate for differentiating bacterial meningitis from aseptic meningitis: A meta-analysis Sakushima et al. 2011 33 studies included (both adults and children)
n=934 ABM, n=951 AVM
Systematic review and meta-analysis Sensitivity 93% Excluded non-English studies
No gray literature
Excluded studies with comparator groups including but not exclusively comprised of AVM
Specificity 96%
LR+ 22.9
LR- 0.07
Author Commentary:
Distinguishing acute bacterial meningitis from acute viral meningitis can be challenging. While a strategy of treating all possible cases of ABM with broad spectrum antibiotics until CSF cultures result is commonly employed, this strategy may lead to antibiotic resistance and unnecessary hospitalization. A combination of CSF white blood cell count/differential, CSF glucose, and CSF protein is commonly used to distinguish ABM from AVM. Unfortunately these tests all suffer from suboptimal sensitivity and specificity. The ideal test would be maximally sensitive and specific, rapidly available, and cheap. Despite not being commonly used, CSF lactate has been widely studied and appears to satisfy all three domains. The median cutoff used in the included studies was 3.5mM (~31mg/dL), with the majority of studies using enzymatic assays. As with most CSF tests including the gold-standard culture, CSF lactate's utility is somewhat limited in patients pretreated with antibiotics. In such cases, a lower cutoff should be used to maintain sufficient sensitivity.
Bottom Line:
CSF lactate at a cutoff of 3.5mM appears to be both a sensitive and specific test for distinguishing acute bacterial meningitis from acute viral meningitis. With over 30 studies supporting its use over the past 40 years, it appears ready for routine use.
References:
  1. Abro et al.. CSF lactate level: a useful diagnostic tool to differentiate acute bacterial and viral meningitis.
  2. Abro et al.. Cerebrospinal fluid analysis: acute bacterial versus viral meningitis
  3. Berg et al.. Cerebrospinal fluid lactate in the diagnosis of meningitis. Diagnostic value compared to standard biochemical methods.
  4. Briem et al.. Comparison between cerebrospinal fluid concentrations of glucose, total protein, chloride, lactate, and total amino acids for the differential diagnosis of patients with meningitis.
  5. Brook et al.. Measurement of lactic acid in cerebrospinal fluid of patients with infections of the central nervous system.
  6. Buch et al.. Cerebrospinal fluid lactate as a marker to differentiate between community-acquired acute bacterial meningitis and aseptic meningitis/encephalitis in adults: a Danish prospective observational cohort
  7. Chen et al.. The clinical diagnostic significance of cerebrospinal fluid d-lactate for bacterial meningitis
  8. Curtis et al.. Cerebrospinal fluid lactate and the diagnosis of meningitis.
  9. D'Souza et al.. Lactic-acid concentration in cerebrospinal fluid and differential diagnosis of meningitis.
  10. Ellis and Oei. Cerebrospinal fluid lactic acid: a valuable aid in the of diagnosis septic meningitis.
  11. Ferguson and Tearle. Gas liquid chromatography in the rapid diagnosis of meningitis.
  12. Gastrin et al.. Rapid diagnosis of meningitis with use of selected clinical data and gas-liquid chromatographic determination of lactate concentration in cerebrospinal fluid.
  13. Genton and Berger. Cerebrospinal fluid lactate in 78 cases of adult meningitis.
  14. Giulieri et al.. CSF lactate for accurate diagnosis of community-acquired bacterial meningitis
  15. Gould et al.. The use of cerebrospinal fluid lactate determination in the diagnosis of meningitis.
  16. Herold et al.. Lactic acid in cerebrospinal fluid: evaluation and application of an automated enzymatic assay.
  17. Hurd et al.. Use of cerebrospinal fluid lactate levels in the diagnosis of bacterial meningitis.
  18. Jordan et al.. CSF lactate in diseases of the CNS.
  19. Kleine et al.. New and old diagnostic markers of meningitis in cerebrospinal fluid (CSF).
  20. Komorowski et al.. Cerebrospinal fluid lactic acid in diagnosis of meningitis.
  21. Komorowski et al.. Comparison of cerebrospinal fluid C-reactive protein and lactate for diagnosis of meningitis.
  22. Lagi et al.. Proposal for a New Score-Based Approach To Improve Efficiency of Diagnostic Laboratory Workflow for Acute Bacterial Meningitis in Adults
  23. Landaas and Von Der Lippe. Chemical analyses for early differential diagnosis between bacterial and viral meningitis.
  24. Lannigan et al.. Evaluation of cerebrospinal fluid lactic acid levels as an aid in differential diagnosis of bacterial and viral meningitis in adults.
  25. Lauwers. Lactic-acid concentration in cerebrospinal fluid and differential diagnosis of meningitis.
  26. Lester et al.. Value of CSF lactate in the differential diagnosis between bacterial meningitis and other diseases with meningeal involvement.
  27. Lindquist et al.. Value of cerebrospinal fluid analysis in the differential diagnosis of meningitis: a study in 710 patients with suspected central nervous system infection.
  28. Mandal et al.. How useful is cerebrospinal fluid lactate estimation in differential diagnosis of meningitis?
  29. Patterson et al.. Handheld Point-of-Care Cerebrospinal Fluid Lactate Testing Predicts Bacterial Meningitis in Uganda
  30. Ponka et al.. The differential diagnosis of bacterial and aseptic meningitis using cerebrospinal fluid laboratory tests.
  31. Schwarz et al.. Serum procalcitonin levels in bacterial and abacterial meningitis.
  32. Viallon et al.. Meningitis in adult patients with a negative direct cerebrospinal fluid examination: value of cytochemical markers for differential diagnosis
  33. de Almeida et al.. Quantitation of cerebrospinal fluid lactic acid in infectious and non-infectious neurological diseases
  34. Huy et al.. Cerebrospinal fluid lactate concentration to distinguish bacterial from aseptic meningitis: a systemic review and meta-analysis
  35. Sakushima et al.. Diagnostic accuracy of cerebrospinal fluid lactate for differentiating bacterial meningitis from aseptic meningitis: A meta-analysis