1. Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798 799
Original article
1Division of Emergency
Medicine, Department
of Pediatrics, Children’s
Hospital Boston and Harvard
Medical School, Boston,
Massachusetts, USA
2Division of Infectious
Diseases, Department
of Pediatrics, Children’s
Hospital Boston and Harvard
Medical School, Boston,
Massachusetts, USA
3Departments of Emergency
Medicine and Pediatrics,
University of California, Davis
School of Medicine,, Davis,
California, USA
Correspondence to
Lise E Nigrovic, Division
of Emergency Medicine,
Department of Pediatrics,
Children’s Hospital Boston and
Harvard Medical School,
300 Longwood Avenue,
Boston, MA 02115, USA;
lise.nigrovic@childrens.
harvard.edu
This work was presented in
part at the American Academy
of Pediatrics, National
Conference and Exhibition,
14 October 2011, Boston,
Massachusetts, USA.
Received 1 February 2012
Accepted 28 May 2012
ABSTRACT
Objective The Bacterial Meningitis Score, a derived
and validated clinical decision rule, identifies children
with cerebrospinal fluid (CSF) pleocytosis who are at
very low risk of bacterial meningitis. Low-risk features
include the following: negative CSF Gram stain, CSF
absolute neutrophil count (ANC) <1000 cells/µl, CSF
protein <80 mg/dl, peripheral blood ANC <10 000
cells/µl and no seizure at or prior to initial presentation.
The study objective of the present work was to calculate
the performance of the Bacterial Meningitis Score by
performing a meta-analysis of all published validation
studies.
Methods A meta-analysis of all studies published
between 2002 and 2012 was performed, evaluating
the performance of the Bacterial Meningitis Score
in children with CSF pleocytosis. Study quality was
assessed using the assessment of diagnostic accuracy
studies instrument and then the test performance of the
prediction rule was calculated.
Results From 8 studies, 5312 patients were identified,
of whom 4896 (92%) had sufficient clinical data to
calculate the Bacterial Meningitis Score. Bacterial
meningitis was diagnosed in 1242 children (23% of study
patients). The combined sensitivity of the Bacterial
Meningitis Score for bacterial meningitis was 99.3%
(1224/1233; 95% CI 98.7% to 99.7%), specificity 62.1%
(2274/3663; 95% CI 60.5% to 63.7%) negative predictive
value 99.7% (2274/2283, 95% CI 99.3% to 99.9%),
positive likelihood ratio 2.6 (95% CI 2.5 to 2.7) and
negative likelihood ratio 0.01 (95% CI 0.01 to 0.02).
Conclusions The Bacterial Meningitis Score is a highly
accurate clinical scoring system that could be used to
assist clinical decision making for the management of
children with CSF pleocytosis.
INTRODUCTION
In regions of the world with high vaccination
rates, the incidence of bacterial meningitis has
declined substantially due to highly effective con-
jugate vaccines.1–5 However, children with cere-
brospinal fluid (CSF) pleocytosis are frequently
hospitalised and given broad-spectrum antibiotics
while awaiting the results of bacterial cultures,
which may take 48 h to reliably exclude bacterial
growth.6–8
Children at very low risk for bacterial menin-
gitis can be considered for outpatient manage-
ment if they are otherwise well appearing and
have adequate clinical follow-up. The Bacterial
Meningitis Score clinical prediction rule was
derived and internally validated from a retrospec-
tive cohort of 696 children with CSF pleocytosis
hospitalised at a single institution.9 Although the
Meta-analysis of bacterial meningitis score
validation studies
Lise E Nigrovic,1 Richard Malley,1,2 Nathan Kuppermann3
Bacterial Meningitis Score performed with very
high accuracy, clinical application was limited by
the small study sample size, single-centre design
with a highly referred population, lack of external
validation, as well as ongoing changes in the epi-
demiology of bacterial meningitis related to the
introduction of bacterial conjugate vaccines.5
The ‘real-world’ performance of a clinical pre-
diction rule is most accurately assessed by its
application in a variety of clinical settings. We
initially tested the Bacterial Meningitis Score in
a large multicentre US study of children with CSF
pleocytosis.10 The Bacterial Meningitis Score has
also been evaluated in six additional studies by
independent investigators.11–16 In this study, we
sought to measure the accuracy of the Bacterial
Meningitis Score by aggregating the patients from
the eight validation studies and to report the per-
formance of the prediction rule in the combined
population.
METHODS
Study design
We performed a fixed-effects meta-analysis of the
published Bacterial Meningitis Score validation
studies.17 18 We searched the Medline and Embase
electronic databases for eligible articles published
between October 2002 and March 2012. We used
the following search terms: Bacterial Meningitis
Score, bacterial meningitis prediction and menin-
gitis validation study. Additionally, we reviewed
all publications that referenced the derivation
study.9 One publication that is currently in press
What is already known on this subject
The Bacterial Meningitis Score, a previously
derived and validated clinical prediction rule,
identifies children with cerebrospinal fluid (CSF)
pleocytosis who are at very low risk for bacterial
meningitis.
What this study adds
The Bacterial Meningitis Score performed well in
eight published validation studies and could be
used to assist clinical decision
making for children with CSF pleocytosis.
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4 July 2012

2. 800 Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798
Original article
as the I2 statistic to assess for consistency of the results across
studies.
As a prespecified subgroup analysis, we also calculated the
performance of the Bacterial Meningitis Score in the sub-
group of study patients not included in either the internal9 or
the multicentre10 validation studies conducted by this study’s
investigators.
We performed statistical calculations using Stata statistical
software.24
RESULTS
We identified 405 published studies using our search strategy
of which 10 met our inclusion criteria. We excluded an adult
cohort study (111 patients)25 and a paediatric cohort study (91
patients)26 because insufficient details were provided to allow
us to assess the patient population or the antibiotic pretreat-
ment status. We included the remaining eight studies in this
analysis (table 2).9–16 We assessed the quality of the included
studies using the QUADAS-2 instrument (table 3).22
The eight included studies had the following study designs:
case series (one study),13 case-control (one study),12 retrospec-
tive cohort (five studies)9–11 14 16 and prospective cohort (one
study).15 Study patients presented for emergency care in the
USA,9 10 Western Europe11 12 and South America (Argentina).15
Of the 5312 included children, 1242 (23%) had bacterial men-
ingitis and 4070 (77%) had aseptic meningitis.
The patient populations for each validation study varied
slightly (table 4). One study was limited to patients with bac-
terial meningitis13 and another had available procalcitonin
results.14 Five studies were of hospitalised children, including
patients referred for management of meningitis.9 11 12 14–16 One
other study was conducted in the emergency department10
and the other was a nationwide meningitis registry (216
participating institutions).13 27 While Haemophilus influenzae
typeBvaccinationrateswerehighinallstudypopulations,only
onepopulation(USA)hadwidespreadseven-valentpneumococ-
cal conjugate vaccination available during the study period.10
28 None of the populations had routine meningococcal vacci-
nation during the study period. All studies excluded children
with immunosuppressive medical conditions or therapies,
while the other exclusion criteria varied by study: critical
illness,9 10 14–16 recent neurosurgery or presence of a ventricular
shunt,9 10 12–16 purpura,9 10 focal bacterial infections requiring
parenteral antibiotic treatment,9 10 traumatic LP,12 13 16 Lyme
meningitis16 or transferred patients.16
While in all studies the bacterial meningitis case definition
included patients with CSF culture positive for a bacterial
pathogen, they varied in whether patients with a positive CSF
Gram stain,12 latex agglutination test,12 14–16 CSF bacterial PCR
test15 16 or CSF pleocytosis with a positive blood culture but
negative CSF culture9–11 13 15 16 were considered to have bacte-
rial meningitis. Although patients pretreated with antibiotics
were excluded, the time between antibiotic administration
and diagnostic LP defined as antibiotic pretreatment was not
standardised.
The Bacterial Meningitis Score could be calculated for 4896
(92%) of the 5312 patients in the aggregated patient population
(table 5). Patients from all studies contributed to the calculation
of test sensitivity. Patients from seven studies were included in
the calculation of test specificity and from six studies in the
predictive value and likelihood ratio calculations. The Bacterial
Meningitis Score had an overall test sensitivity of 99.3% (95%
CI 98.7 to 99.7%) (figure 1). For the primary outcome measure
(sensitivity), we found no evidence for heterogeneity between
was identified by a published abstract and we subsequently
communicated with the corresponding author. We reviewed
potentially eligible studies to identify those that included chil-
dren younger than 18 years of age as well as sufficient informa-
tion to calculate the Bacterial Meningitis Score. We excluded
patients used for the prediction model derivation conducted by
the study investigators.9
Data collection
We reviewed eligible studies to determine study design, inclu-
sion and exclusion criteria, patient population and case defi-
nitions. Because antibiotic pretreatment can render bacterial
cultures falsely negative19 20 and also impact CSF profiles,21
we excluded studies in which patients had received antibiot-
ics prior to lumbar puncture (LP) (defined as ‘antibiotic pre-
treatment’). We contacted the corresponding authors of the
published studies to clarify study methods, as necessary. We
excluded studies for which we could not verify study proce-
dures. We assessed the quality of the included studies using
the Quality Assessment of Diagnostic Accuracy Studies 2
(QUADAS-2) instrument.22
Bacterial meningitis score performance
For each of the included studies, we determined the number of
patients with bacterial and aseptic meningitis using study-spe-
cific case definitions. Children with none of the five high-risk
Bacterial Meningitis Score predictors were classified at ‘very
low risk’ for bacterial meningitis (table 1).9 10 Children with
one or more high-risk predictor were classified as ‘not low risk’
even if other predictors were missing. Otherwise, children
missing predictors included in the Bacterial Meningitis Score
were excluded from the prediction rule validation.
Statistical analysis
We abstracted the Bacterial Meningitis Score as calculated by
the study investigators. We then calculated the performance of
the dichotomised Bacterial Meningitis Score (‘very low risk’ vs
‘not very low risk’) in the aggregated patient population. Our
primary outcome was the prediction rule sensitivity, which
we calculated for each of the included studies. Our secondary
outcomes were specificity, negative predictive value (NPV),
positive predictive value (PPV) as well as positive and nega-
tive likelihood ratios. We used patients from case-control and
cohort studies for calculation of sensitivity and specificity, but
not for PPV and NPV. We used children from cohort studies for
the calculation of sensitivity, specificity, NPV, PPV as well as
likelihood ratios using standard techniques.23
We present the pooled effects as a point estimate with 95%
CI using binomial methods with a Forest plot for the primary
outcome measure. We calculated the Q statistic (χ2-distributed
with one less than the number of included studies degrees of
freedom) to assess the heterogeneity between studies as well
Table 1 Bacterial Meningitis Score9
Bacterial Meningitis Score predictors Criteria
CSF Gram stain Positive result
CSF ANC ≥1000 cells/mm3
CSF protein ≥80 mg/dl
Peripheral blood ANC ≥10 000 cells/mm3
Seizure Onset at or prior to time of presentation
ANC, absolute neutrophil count; CSF, cerebrospinal fluid.
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3. Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798 801
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Table 2 Published Bacterial Meningitis Score validation studies
Study Journal Study years
Bacterial
meningitis,
N (%)
Aseptic
meningitis,
N (%) Study design
Admission
rate, % Country
PCV7
implemented
Nigrovic et al9 Pediatrics 1994–2000 38 (16%) 196 (84%) Single-centre retrospective
cohort
100% USA No
Dubos et al12 Arch Dis Child 1995–2004 20 (12%) 146 (88%) Retrospective with selected
cases and controls
100% France No
Piérart and Lepage11 Rev Med Liege 2000–2005 29 (10%) 248 (90%) Retrospective cohort 100% Belgium No
Nigrovic et al10 JAMA 2002–2004 121 (4%) 3174 (96%) A 20-centre retrospective
cohort
81% USA Yes
Dubos et al13 J Pediatr 2001–2005 898 (100%) 0 (0%) Nationwide meningitis registry 100% France No
Dubos et al14 Arch Dis Child 1996–2005 96 (48%) 102 (52%) A six-centre retrospective
cohort
100% Western
Europe
No
Agüero et al15 Arch Argent
Pediatr
2006–2007 14 (20%) 56 (80%) Single-centre prospective
cohort
100% Argentina No
Tuerlinckx et al16 Acta Clinica
Belgica
1996–2008 26 (15%) 148 (85%) A two-centre retrospective
cohort
100% Belgium No
Totals 1242 (23%) 4070 (77%) 88%
PCV7, seven-valent pneumococcal conjugate vaccine.
Table 3 Quality assessment of diagnostic accuracy studies 222
Study
Risk of bias Applicability concerns
Patient
selection Index test
Reference
standard
Flow and
timing
Patient
selection Index test
Reference
standard
Nigrovic et al9 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Dubos et al12 ☻ ☺ ? ☺ ☻ ☺ ?
Piérart and Lepage11 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Nigrovic et al10 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Dubos et al13 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Dubos et al14 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Agüero et al15 ☺ ☺ ☺ ☺ ☺ ☺ ☺
Tuerlinckx et al16 ☺ ☺ ☺ ☺ ☺ ☺ ☺
☺, low risk; ☻, high risk; ?, unclear risk.
Table 4 Study definitions
Study Patient population Inclusion criteria Exclusion criteria Bacterial meningitis definition
Pretreated
patients
included?*
Nigrovic et al9 Hospitalised patients CSF WBC ≥8 cells/mm3
Positive CSF culture
Age 1 month to 18 years
Critical illness
Neurosurgery or shunt
Immunodeficiency
Focal bacterial infections
Purpura fulminans
Positive CSF culture
CSF pleocytosis plus positive blood
culture
No
Dubos et al12 Hospitalised patients CSF WBC ≥7 cells/mm3 Neurosurgical disease Positive CSF Gram stain, culture or latex
agglutination
No
Immunodeficiency
Age 1 month to 16 years Traumatic LP
Referred patients
Piérart and
Lepage 11
Hospitalised patients CSF WBC ≥6 cells/mm3 Tuberculosis or Lyme meningitis Positive CSF culture or bacterial PCR No
Age 1 month to 15 years Immunosuppression CSF pleocytosis plus positive blood culture
Nigrovic et al10 Emergency department
patients
CSF WBC ≥10 cells/mm3 Critical illness Positive CSF culture No
Neurosurgery or shunt CSF pleocytosis plus positive blood culture
Immunodeficiency
Positive CSF culture Focal bacterial infections
Age 1 month to 18 years Purpura
Dubos et al13 Bacterial meningitis
registry
CSF WBC ≥7 cells/mm3 Critical illness Positive CSF culture or latex agglutination No
Neurosurgery or shunt
Age 1 month to 18 years Immunodeficiency CSF pleocytosis plus positive blood culture
Traumatic LP
Dubos et al14 Hospitalised patients CSF WBC ≥8 cells/mm3 Critical illness Positive CSF culture, latex agglutination or
bacterial PCR
No
Neurosurgery or shunt
Age 1 month to 18 years Immunodeficiency CSF pleocytosis plus positive blood culture
Procalitonin obtained Focal bacterial infections
(Continued)
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4. 802 Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798
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Table 4 (Continued)
Study Patient population Inclusion criteria Exclusion criteria Bacterial meningitis definition
Pretreated
patients
included?*
Agüero et al15 Hospitalised patients CSF WBC ≥8 cells/mm3 Critical illness Positive CSF culture No
Neurosurgery or shunt
Age 1 month to 18 years Immunodeficiency CSF pleocytosis plus positive blood culture,
bacterial PCR or latex agglutinationFocal bacterial infections
Tuerlinckx et al16 Hospitalised patients CSF WBC ≥9 cells/mm3 Critical illness Positive CSF culture No
Purpura
Neurosurgery CSF pleocytosis plus positive blood culture,
bacterial PCR or latex agglutination
Immunodeficiency
Traumatic LP
Lyme meningitis
*Pretreatment defined as antibiotics administered before lumbar puncture.
CSF, cerebrospinal fluid; LP, lumbar puncture; WBC, white blood cells.
studies (p=0.88) or results (I2=0.0) in our meta-analysis.
Children categorised as ‘not very low risk’ by the Bacterial
Meningitis Score had a positive likelihood ratio for bacterial
meningitis of 2.6 (95% CI 2.5 to 2.7) and those categorised as
‘very low risk’ by the Bacterial Meningitis Score had a negative
likelihood ratio of 0.01 (95% CI 0.01 to 0.02).
Among the 1783 children included in the 6 validation stud-
ies not conducted by this study’s investigators, 1083 (61%) had
bacterial meningitis and 700 (39%) had aseptic meningitis. In
this subgroup, the Bacterial Meningitis Score had a sensitivity
of 99.3% (95% CI 98.6% to 99.7%), specificity of 61.0% (95%
CI 57.3 to 64.7%), NPV of 98.3% (95 CI 96.6% to 99.3%) and
PPV 28.1% (95% CI 22.6% to 33.9%). We could not exclude the
possibility that children with bacterial meningitis from 1 of
the 216 centres in the bacterial meningitis registry13 may also
have been included in a more recent multicentre retrospec-
tive cohort study (personal communication, M. Chalumeau,
Hôpital de Paris). However, when we excluded this cohort
study, the Bacterial Meningitis Score performed similarly
(data not shown).
Nine patients with bacterial meningitis were classified as
‘very low risk’ by the Bacterial Meningitis Score (table 5). Of
these, three were younger than 2 months of age (an age at which
we previously recommended the Bacterial Meningitis Score
not be applied)10 and three others presented with petechiae
or purpura on examination.13 The three misclassified patients
with bacterial meningitis who were older than 2 months and
who did not have a petechial or purpuric rash on presenting
examination are described in table 6 (patients 3, 6 and 9). All
three of these children had meningococcal meningitis.
DISCUSSION
The Bacterial Meningitis Score, a clinical prediction rule to
identify children with CSF pleocytosis who are at very low risk
of bacterial meningitis, has been validated in eight published
studies.9–16 In this meta-analysis, the score had a sensitivity of
99.3% (95% CI 98.7% to 99.7%) for bacterial meningitis. The
included studies were of high quality and did not have signifi-
cant study heterogeneity. Although the study designs, patient
population, inclusion and exclusion criteria as well as bacterial
meningitis case definition differ between studies, the Bacterial
Meningitis Score performed with a high degree of accuracy.
When the validation studies conducted by this study’s investi-
gators were excluded, the results did not change.
A clinical prediction rule is a decision-making tool that com-
bines history, physical examination and laboratory results to
predict the probability of an outcome for an individual patient.
Clinical prediction rules must be developed and validated
according to rigorous methodological standards prior to wide-
spread implementation.29–31 While prospective rather than
retrospective validation is typically preferred, because of the
rarity of bacterial meningitis in high-income countries,5 such
a validation is not readily feasible; accordingly, seven of the
eight included studies were retrospective. We do not believe
that the retrospective validation introduced important biases
since the predictors are objective. Four of the five factors are
laboratory values and one clinical factor (seizure at or prior to
the time of initial presentation), should be reliably recorded in
the medical records.32 33
For children younger than 18 years of age in the USA, the
incidence of bacterial meningitis caused by H influenzae,
Streptococcus pneumoniae, group B streptococcus (GBS), Neisseria
meningitidis or Listeria monocytogenes declined 31% over the past
decade.5 Despite these substantial declines in the overall inci-
dence, the bacterial meningitis case death rate has remained
unchanged at 7%; most affected children do not have pre-
disposing medical conditions.5 Given the high mortality and
morbidity, clinicians must still maintain a high index of sus-
picion for bacterial meningitis. Looking ahead, the increasing
availability of the 13-valent S pneumoniae and quadrivalent N
meningitidis conjugate vaccines in high-income countries will
further decrease the incidence of bacterial meningitis. The
Bacterial Meningitis Score can support clinician decision mak-
ing by providing a highly accurate initial assessment of the
risk of bacterial meningitis for children with CSF pleocytosis.
We recommend that the Bacterial Meningitis Score, as with
other clinical prediction rules, be used to assist rather than
replace clinical decision making.34 Although the score per-
forms extremely well, it is highly unlikely to develop a clinical
prediction rule with 100% accuracy in all patient populations.35
Of note, the misclassified patients who presented without
petechia or purpura all had meningococcal meningitis which
has been previously described to present without CSF pleocy-
tosis.36 Nevertheless, children with a very low-risk Bacterial
Meningitis Score are at such low risk of bacterial meningi-
tis that they may be considered for outpatient management,
potentially after the administration of a long-acting parenteral
antibiotic. Currently, most children with CSF pleocytosis are
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5. Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798 803
Original article
hospitalised and given parenteral antibiotics in order to avoid
missing the very few with bacterial meningitis. Application
of the Bacterial Meningitis Score could substantially reduce
unnecessary hospitalisation of children with aseptic meningi-
tis, while still providing a safety margin by the administration
of long-acting antibiotic prior to culture results. As we have
previously recommended,10 however, the Bacterial Meningitis
Score should not be applied to ill-appearing children, infants 2
months and younger, in whom the risk of bacterial meningitis
is highest5 and to those with physical examinations sugges-
tive of invasive bacterial infection (eg, those with petechiae or
purpura).37 This approach will further reduce the risk of mis-
classification of children with bacterial meningitis.
Furthermore, biologic markers of inflammation have been
investigated for their ability to discriminate between cases of
bacterial and aseptic meningitis. For example, CSF lactate38 39 and
serum procalcitonin40 41 are higher in children with bacterial than
aseptic meningitis, although there is overlap in levels of these bio-
markers. Diagnostic assays that use RNA expression to identify
host response to specific pathogens are currently being studied in
the clinical setting.42–44 In the future, these novel assays might
allow rapid identification of specific meningitis pathogens, or
host responses associated with bacterial meningitis.
Our study has some limitations. First, as most of the vali-
dation studies were retrospective, we could not evaluate the
general appearance of the patients, which plays an important
role in clinical decision making. Certain clinical factors such
as the presence of petechiae or purpura could not be evalu-
ated in all studies. Nevertheless, the accuracy of the Bacterial
Meningitis Score remained very high in each of the evaluated
studies. Second, we were only able to include children who
had sufficient clinical data to apply the Bacterial Meningitis
Score from published validation studies. Given the number of
patients evaluated in these studies and the objective nature
of the variables in the score, it is unlikely that the model
would have performed substantially differently in patients
with missing variables. Third, we could not exclude the pos-
sibility that a few children with bacterial meningitis from
a single centre may have been represented in two included
studies.13 14 However, the prediction model performed simi-
larly if this recent study was excluded (and therefore eliminat-
ing the possibility of patient redundancy). Fourth, we were
unable to include patients from the case-control or registry
studies in the calculations of NPV, PPV or likelihood ratios as
these calculations require population prevalence. The variabil-
ity between experimental definitions and methods may have
reduced our ability to accurately combine the study patients.
However, the similar performances of the model across a wide
variety of clinical settings and patient populations as well as
the lack of heterogeneity in the sensitivity and NPV estimates
increase the generalisability of our findings. Furthermore, we
recognise that there is a preponderance (almost two-thirds) of
patients from a single validation study.10 To address a poten-
tial skewing effect, we performed an additional subgroup
analysis after excluding studies conducted by this study’s
investigators, and found similar results to the main analysis.
Finally, the Bacterial Meningitis Score does not predict the
likelihood of other central nervous system infections such
as herpes simplex virus, Lyme45–47 or tuberculous meningi-
tis. Therefore, this clinical prediction rule should be used in
concert with careful clinical assessment of the patient, which
would include consideration of these other important treat-
able infections.
Table5PerformanceoftheBacterialMeningitisScore(BMS)
Study
No.ofbacterial
meningitiscases
withverylow
riskBMS(=0)
No.ofaseptic
meningitiscases
withverylowrisk
BMS(=0)
No.ofbacterial
meningitiscases
withnotlowrisk
BMS(≥1)
No.ofaseptic
meningitiscases
withnotlowrisk
BMS(≥1)Sensitivity%(95%CI)Specificity%(95%CI)
Negativepredictive
value%(95%CI)
Positivepredictivevalue
%(95%CI)
Nigrovicetal901443852100%(91%to100%)42%(34%to51%)100%(98%to100%)42%(32%to53%)
Dubosetal120862045100%(84%to100%)66%(57%to73%)NANA
PiérartandLepage1101632985100%(88%to100%)66%(60%to71%)100%(96%to100%)25%(18%to34%)
Nigrovicetal1021712119107098%(94%to100%)62%(60%to63%)99.9%(99.6%to100%)11%(9%to13%)
Dubosetal135NA884NA99%(99%to100%)NANANA
Dubosetal140539649100%(96%to100%)52%(42%to62%)NANA
Agüeroetal150251431100%(78%to100%)69%(58%to80%)100%(94%to100%)31%(18%to47%)
Tuerlinckxetal16291245792%(75%to99%)61(53%to69%)98%(92%to100%)30%(20%to41%)
Total922741224138999.3%(98.7%to99.7%)62.1%(60.5%to63.7%)99.6%(99.3%to99.8%)28.1%(22.6%to33.9%)
NA,notapplicable.
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6. 804 Arch Dis Child 2012;97:799–805. doi:10.1136/archdischild-2012-301798
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Conclusions
In summary, the Bacterial Meningitis Score performed with
a high degree of diagnostic accuracy in eight validation studies.
This score, in conjunction with clinical judgment can identify chil-
dren with CSF pleocytosis who are at very low risk for bacterial
meningitis. To minimise misclassification of children with bacte-
rial meningitis, we recommend that the Bacterial Meningitis Score
only be applied to non-ill-appearing children older than 2 months,
who do not have either petechiae or purpura on examination and
have not been pretreated with antibiotics. For those children at
very low risk, who have adequate clinical follow-up, clinicians
could consider outpatient treatment after administration of a long-
acting parenteral antibiotic. Future studies should focus on the
implementation of the Bacterial Meningitis Score to prospectively
identify children who are at very low risk of bacterial meningitis.
Contributors LEN conceived the study and drafted the manuscript. LEN, RM and
NK conducted the data analysis, interpreted the data and critically reviewed the
manuscript.
Acknowledgements The authors would like to thank Michael C Monuteaux ScD
(Division of Emergency Medicine, Children’s Hospital; Boston, Massachusetts,
USA) for his help with statistical analysis.
Competing interests None.
Provenance and peer review Not commissioned; externally peer reviewed.
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Table 6 Characteristics of children with bacterial meningitis who were misclassified as very low risk by the Bacterial Meningitis Score
Patient
no. Study
Patient age
(years)
Petechiae or
purpura
History of
seizure
Peripheral
ANC (cells/µl)
CSF ANC
(cells/µl)
CSF protein
(mg/dl)
Gram stain
positive Bacterial pathogen
1 Nigrovic et al10 0.2 No No 8100 0 31 No Escherichia coli
2 Nigrovic et al10 0.1 No No 6800 497 65 No Escherichia coli
3 Dubos et al13 0.3 No No 7744 13 61 No Neisseria meningitidis
4 Dubos et al13 0.7 Yes No 3600 32 25 No Neisseria meningitidis
5 Dubos et al13 5.4 Yes No 9400 30 30 No Neisseria meningitidis
6 Dubos et al13 3.4 No No 1517 60 20 No Neisseria meningitidis
7 Dubos et al13 0.1 No No 3270 ≤8 46 No Streptococcus pneumoniae
8 Tuerlinckx et al16 2.5 Yes No 7683 26 21 No Neisseria meningitidis
9 Tuerlinckx et al16 15 No No 7689 22 46 No Neisseria meningitidis
ANC, absolute neutrophil count; CSF, cerebrospinal fluid.
Figure 1 Forest plot showing Bacterial Meningitis Score sensitivity with 95% CI for individual studies
(and a pooled estimate).
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