- Email: [email protected]
Diagnosis of neurobrucellosis in resource-limited real-world settings: A case-series of 8 patients
Accepted Manuscript Diagnosis of neurobrucellosis in resource-limited real-world settings: A case-series of 8 patients
S. Despotopoulos, K. Akinosoglou, T. Tzimas, N. Akritidis, C. Gogos PII: DOI: Reference:
S0022-510X(17)30398-2 doi: 10.1016/j.jns.2017.06.024 JNS 15399
To appear in:
Journal of the Neurological Sciences
Received date: Revised date: Accepted date:
9 May 2017 11 June 2017 15 June 2017
Please cite this article as: S. Despotopoulos, K. Akinosoglou, T. Tzimas, N. Akritidis, C. Gogos , Diagnosis of neurobrucellosis in resource-limited real-world settings: A caseseries of 8 patients. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Jns(2017), doi: 10.1016/j.jns.2017.06.024
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Dear Editor,
Diagnosis of neurobrucellosis in resource-limited real-world settings: A case-series of 8 patients
RI
PT
S. Despotopoulos1 *, K. Akinosoglou2,3 *, T. Tzimas1 , N. Akritidis1 , C. Gogos2,3
SC
1 Department of Internal Medicine, General Hospital of Ioannina, “G Hatzikosta” Greece 2 Department of Internal Medicine, University Hospital of Patras, Greece
NU
3 Department of Infectious Diseases, University Hospital of Patras, Greece
MA
*These authors equally contributed to this work
ED
Correspondence at
EP T
Karolina Akinosoglou MD,PhD
Department of Internal Medicine and Infectious Disease
AC C
University Hospital of Patras, 26504 Rio Greece Tel:+302610999582
Email: [email protected]
ACCEPTED MANUSCRIPT ABSTRACT Brucellosis is a common zoonotic infection in many parts of the world including the areas around the Mediterranean. Neurobrucellosis represents an uncommon site in <5% of cases. Diagnosis is based on high clinical suspicion, as well as a combination of complex serologic testing
and
abnormal cranial imaging.
Unfortunately,
real-word
settings
often
lack
sophisticated diagnostic modalities, while stringent budget does not allow for repeated
PT
confirmatory testing with alternative methods. In response to the recent article by Erdem et al reporting the presence of diffuse inflammation in MRI, in approximately 45% of patients
RI
with neurobrucellosis, we hereby report our experience with 8 patients presenting with neurobrucellosis in an endemic area, whose diagnosis and management was successfully
SC
driven by common agglutination tests and neglected Rose Bengal test (RBT) in serum and CSF. The authors argue that even though these methods have raised concerns upon their
NU
sensitivity and specificity – currently being surpassed by more complex methodology including ELISA or PCR -, , in resource-limited settings that burden of the disease in high,
MA
re-introduction and simple modification of cheap, non-complex methods like RBT could suffice. Complementary methods should be employed if and where available.
ED
KEY WORDS
AC C
EP T
Neurobrucellosis; Rose Bengal; Wright; Serum Agglutination Test;
ACCEPTED MANUSCRIPT Dear Editor, We read with great interest the recent article by Gündüz et al reporting isolated spinal cord involvement in a case of neurobrucellosis with normal MRI findings (1). Although neurobrucellosis is rare it should be considered in patients with obscure neurologic manifestations in endemic settings (2), even when MRI is negative (1). When positive, MRI findings are non-specific but suggestive of central nervous system disease, showing presence
PT
of diffuse inflammation in a significant number of patients, while inflammatory findings seem to be associated with the duration of symptoms, presence of polyneuropathy and
RI
radiculopathy, high CSF protein level, and low CSF/serum glucose rate. (3) While cranial imaging can be very helpful, in the era of stringent budget, one must consider the difficulty to
SC
employ diagnostic modalities such as MRI in resource limited settings and the need to turn to cheaper modalities. Hence; in response, we present our experience with 8 patients, presenting
NU
with signs of meningoencephalitis finally diagnosed with neurobrucellosis in an endemic area, where diagnosis and treatment was driven by serum agglutination test (SAT) and Rose
MA
Bengal Test (RBT) in cerebrospinal fluid (CSF).
Between 2007-2013, 75 new cases of brucellosis were admitted in a secondary medical
care
unit
of
Western
Greece.
Eight
cases
presented
with
signs
ED
meningoencephalitis as this confirmed by clinical presentation and CSF findings.
of Rose
Bengal test (by Dialab®) , SAT (by Fortress diagnostics), conventional CSF and blood
EP T
culture was utilized for diagnosis and follow-up. Unfortunately, at the time, no SAT or RBT titre quantification in CSF, or further diagnostic testing with MRI, ELISA, PCR, Coombs or immunocapture agglutination test was available to be carried out in our – and several other
AC C
secondary medical care – unit(s).
All patients were positive for epidemiologic history and
SAT titres were >1/160. Patient characteristics and laboratory findings are reported in Table 1. Upon diagnosis, all patients received a combination 6-week regimen of doxycycline (100mg twice daily, orally) and rifampicin (600-900mg daily per os, one morning dose), as per international recommendations, with favorable outcomes (4). No relapse of the disease or any residual complications were observed in any of the 8 diagnosed patients, during a oneyear follow-up period while SAT titers gradually diminished and RBT finally disappeared at various time during patients’ 6-week treatment. Brucellosis is a common zoonotic infection in many parts of the world including the areas around the Mediterranean. Neurobrucellosis may develop at any stage of disease and
ACCEPTED MANUSCRIPT presents
with
widely
variable
manifestations,
including
meningoencephalitis,
myelitis,
radiculitis, cranial and peripheral neuropathies, psychiatric manifestations and subarachnoid haemorrhage. Even though, mortality remains low upon prompt diagnosis and antibiotic treatment, survivors commonly suffer permanent complications.(5, 6) Reported incidence may vary, depending on diagnostic facilities and definition of neurobrucellosis, ranging between 3 and 11% in various series (7). However, diagnostic criteria remain problematic and diagnosis is mostly based on a combination of clinical suspicion, serologic markers and
PT
radiologic findings (7), especially in view of increasing introduction of more sophisticated diagnostic modalities. We hereby presented 8 cases of neurobrucellosis in an endemic setting
RI
that diagnostic modalities are scarce, managing dozens cases of brucellosis yearly. All of our
positive CSF-RBT
SC
8 patients were positive for epidemiologic history, hence a serum SAT titre of >1/160 and in combination with clinical manifestations was considered suggestive of
diagnosis
of infectious
diseases,
it
has
NU
neurobrucellosis (7). Although, positive bacterial culture is the reference standard for been
demonstrated
to
be suboptimal in
neurobrucellosis (8). It was no surprise that in only 12.5% of patients, gram negative bacteria
MA
were isolated, both in blood and CSF; frequency similar to previous reports (7). For this reason, numerous practical serological tests including SAT have been utilized and been Even though their sensitivity remains suboptimal in the
ED
robust in the diagnosis of brucellosis.
diagnosis of neurobrucellosis, in resource limited settings they are the only diagnostic modality available while even so, blood serology remains far more sensitive than other
EP T
methods in the diagnosis of CNS involvement (8, 9). However, agglutination reactions at neutral pH have been shown to be prone to false-negative results, due to prozones and blocking and non-agglutinating antibodies, two problems largely solved by carrying the
AC C
agglutinations at acid pH, as in RBT and Brucellacapt (10). RBT has been a simple screening method for the diagnosis of brucellosis however, concerns have been expressed as to its low sensitivity in chronic cases (11) and low specificity in endemic areas (12, 13), fact that has limited its use in view of current more accurate methods (14). This argument might be true in presence and availability of diagnostically more robust tests in well-equipped laboratories and low prevalence areas. However, in our setting, RBT proved to be more sensitive than conventional cultures while RBT positivity did not seem to correlate with serum SAT titres, as also previously noted (8). As Erdem et al have recently shown, although SAT should be preferred over RBT in CSF in probable neurobrucellosis, RBT was not as weak as expected in a retrospective multicentre
ACCEPTED MANUSCRIPT study of 177 cases (8). Similarly in our case series a sensitivity of 100% in CSF-RBT was observed. Even though this discrepancy could be attributed to low number of cases in this report, a number of reasons, including the quality of antigen provided by each manufacturer as well as, interpretation of the test by different users in different settings of short or long evolution, can also be held responsible (10). Even though, CSF-RBT positivity seemed to correlate well between CSF-SAT titres above a certain threshold (>1/40), cases of CSF-SAT negativity with positive CSF-RBT have been recorded (8), suggesting its potential role in
PT
neurobrucellosis diagnosis. Despite concerns relating to discordant results, recent data have come to show that when modified to test serum dilutions, RBT can reach a sensitivity of patients) and
specificity of 100% (contacts), not requiring further
RI
87.4% (infected
SC
confirmation with other more expensive or time-consuming tests (10, 15). In the experience of these authors, neglected RBT can prove a very useful test for the
NU
diagnosis of neurobrucellosis. It needs no sophisticated training or complicated infrastructure, it is extremely cheap, highly sensitive and easily adaptable to test serum dilutions. It should
MA
be re-introduced in the diagnostic armamentarium of neurobrucellosis, in settings where diagnostic modalities such as MRI or PCR remain – or have become – limited, and
AC C
EP T
ED
complemented with other tests where those available.
ACCEPTED MANUSCRIPT REFERENCES 1.
Gunduz T, Tekturk PT, Yapici Z, Kurtuncu M, Somer A, Torun SH, et al.
Characteristics of isolated spinal cord involvement in neurobrucellosis with no corresponding MRI activity: A case report and review of the literature. Journal of the neurological sciences. 2017;372:305-6. 2.
Erdem H, Inan A, Guven E, Hargreaves S, Larsen L, Shehata G, et al. The burden and
PT
epidemiology of community-acquired central nervous system infections: a multinational study. European journal of clinical microbiology & infectious diseases : official publication
3.
RI
of the European Society of Clinical Microbiology. 2017.
Erdem H, Senbayrak S, Meric K, Batirel A, Karahocagil MK, Hasbun R, et al. Cranial
SC
imaging findings in neurobrucellosis: results of Istanbul-3 study. Infection. 2016;44(5):62331.
Ariza J, Bosilkovski M, Cascio A, Colmenero JD, Corbel MJ, Falagas ME, et al.
NU
4.
Perspectives for the treatment of brucellosis in the 21st century: the Ioannina
5.
MA
recommendations. PLoS medicine. 2007;4(12):e317.
Gul HC, Erdem H, Bek S. Overview of neurobrucellosis: a pooled analysis of 187
cases. International journal of infectious diseases : IJID : official publication of the
6.
ED
International Society for Infectious Diseases. 2009;13(6):e339-43. Erdem H, Ulu-Kilic A, Kilic S, Karahocagil M, Shehata G, Eren-Tulek N, et al.
EP T
Efficacy and tolerability of antibiotic combinations in neurobrucellosis: results of the Istanbul study. Antimicrobial agents and chemotherapy. 2012;56(3):1523-8. 7.
Guven T, Ugurlu K, Ergonul O, Celikbas AK, Gok SE, Comoglu S, et al.
AC C
Neurobrucellosis: clinical and diagnostic features. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 2013;56(10):1407-12. 8.
Erdem H, Kilic S, Sener B, Acikel C, Alp E, Karahocagil M, et al. Diagnosis of
chronic brucellar meningitis and meningoencephalitis: the results of the Istanbul-2 study. Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases. 2013;19(2):E80-6. 9.
Araj GF. Update on laboratory diagnosis of human brucellosis. International journal
of antimicrobial agents. 2010;36 Suppl 1:S12-7. 10.
Diaz R, Casanova A, Ariza J, Moriyon I. The Rose Bengal Test in human brucellosis:
a neglected test for the diagnosis of a neglected disease. PLoS neglected tropical diseases. 2011;5(4):e950.
ACCEPTED MANUSCRIPT 11.
Araj GF, Lulu AR, Khateeb MI, Saadah MA, Shakir RA. ELISA versus routine tests
in the diagnosis of patients with systemic and neurobrucellosis. APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. 1988;96(2):171-6. 12.
Konstantinidis A, Minas A, Pournaras S, Kansouzidou A, Papastergiou P, Maniatis A,
et al. Evaluation and comparison of fluorescence polarization assay with three of the currently used serological tests in diagnosis of human brucellosis. European journal of clinical microbiology & infectious diseases : official publication of the European Society of
13.
PT
Clinical Microbiology. 2007;26(10):715-21.
Muma JB, Lund A, Nielsen K, Matope G, Munyeme M, Mwacalimba K, et al.
RI
Effectiveness of Rose Bengal test and fluorescence polarization assay in the diagnosis of
animal health and production. 2009;41(5):723-9.
Gomez MC, Nieto JA, Rosa C, Geijo P, Escribano MA, Munoz A, et al. Evaluation of
NU
14.
SC
Brucella spp. infections in free range cattle reared in endemic areas in Zambia. Tropical
seven tests for diagnosis of human brucellosis in an area where the disease is endemic. Clinical and vaccine immunology : CVI. 2008;15(6):1031-3. Mantur BG, Amarnath SK, Patil GA, Desai AS. Clinical utility of a quantitative Rose
MA
15.
Bengal slide agglutination test in the diagnosis of human brucellosis in an endemic region.
AC C
EP T
ED
Clinical laboratory. 2014;60(4):533-41.
ACCEPTED MANUSCRIPT CONFLICT OF INTEREST STATEMENT On behalf of all authors, the corresponding author states that there is no conflict of interest. ETHICAL STATEMENT Written informed consent was obtained from the patients for publication of their cases.
AC C
EP T
ED
MA
NU
SC
RI
PT
Copies are available to review by the Editor of this journal
ACCEPTED MANUSCRIPT Table 1. Summary of Clinical and Laboratory findings. 1
2
3
4
5
6
7
8
Age/Sex
28/M
35/M
38/M
23/M
60/M
44/F
33/M
61/M
Diagnosi
Mening
Meningo
Mening
Mening
Mening
Mening
Mening
Mening
s
o
encephalit
o
o
o
o
o
o
Patient No
encephal encephal encephal encephal encephal encephal
itis
itis
itis
itis
Clinical
Fever,
Fever,
Fever,
Fever,
Fever,
PT
encephal is
Fever,
Meningi
Fever,
Presenta
meningi
meningis
meningi
meningi
meningi
night
sm,
sweats,
tion
sm
m,
sm,
sm
sm
sweats,
night
meningi
myalgia
myalgias,
myalgia
fatigue
fatigue
fatigue
sweats,
sm,
s,
fatigue,
s,
lethargy
depressi
fatigue
arthralgi
anorexia
disorienta
, fatigue
tion
Blood
Negativ
Positive
Culture
e
Serum
+1/1280
itis
RI
SC
NU MA
itis
on
as
Negativ
Negativ
Negativ
Negativ
Negativ
Negativ
e
e
e
e
e
e
+1/640
+1/640
+1/320
+1/320
+1/160-
+(1/160-
ED
+1/320
itis
1/320
1/10240
SAT
)
Serum
(+)
RBT
positive
EP T
titres (Wright)
(+)
(+)
(+)
(+)
(+)
(+)
positive
positive
positive
positive
positive
positive
positive
4.8
40.8
26
36
30
40
3.9
32
CSF cell
30
898
100
15
50
12
445
9 (68%)
count/μl
(80%)
(76%)
(73%)
(100%)
(78%)
(91%)
(93%)
CSF /plasma Glucose
AC C
(+)
ratio %
(%Lymp h)
70.2
135.5
92.4
12
84
72
90.7
19.4
CSF
Negativ
Positive
Negativ
Negativ
Negativ
Negativ
Negativ
Negativ
Culture
e
e
e
e
e
e
e
CSF
(+)
(+)
(+)
(+)
(+)
(+)
(+)
(+)
RBT
positive
positive
positive
positive
positive
PT
ACCEPTED MANUSCRIPT CSF protein (mg/dl) {15-60}
positive
positive
positive
RI
M:male;F:female; SAT: serum agglutination test; RBT: Rose Bengal Test; CSF: Cerebrospinal
AC C
EP T
ED
MA
NU
SC
fluid
ACCEPTED MANUSCRIPT HIGHLIGHTS
PT RI SC NU MA ED EP T
Diagnosis of neurobrucellosis is problematic in resource-limited endemic settings Rose-Bengal test (RBT) represents a cheap, easy method for the diagnosis of brucellosis RBT has been neglected in view of more accurate diagnostic tests When modified to serum dilutions RBT has a sensitivity of 87.4% and specificity of 100%
AC C
S. Despotopoulos, K. Akinosoglou, T. Tzimas, N. Akritidis, C. Gogos PII: DOI: Reference:
S0022-510X(17)30398-2 doi: 10.1016/j.jns.2017.06.024 JNS 15399
To appear in:
Journal of the Neurological Sciences
Received date: Revised date: Accepted date:
9 May 2017 11 June 2017 15 June 2017
Please cite this article as: S. Despotopoulos, K. Akinosoglou, T. Tzimas, N. Akritidis, C. Gogos , Diagnosis of neurobrucellosis in resource-limited real-world settings: A caseseries of 8 patients. The address for the corresponding author was captured as affiliation for all authors. Please check if appropriate. Jns(2017), doi: 10.1016/j.jns.2017.06.024
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT Dear Editor,
Diagnosis of neurobrucellosis in resource-limited real-world settings: A case-series of 8 patients
RI
PT
S. Despotopoulos1 *, K. Akinosoglou2,3 *, T. Tzimas1 , N. Akritidis1 , C. Gogos2,3
SC
1 Department of Internal Medicine, General Hospital of Ioannina, “G Hatzikosta” Greece 2 Department of Internal Medicine, University Hospital of Patras, Greece
NU
3 Department of Infectious Diseases, University Hospital of Patras, Greece
MA
*These authors equally contributed to this work
ED
Correspondence at
EP T
Karolina Akinosoglou MD,PhD
Department of Internal Medicine and Infectious Disease
AC C
University Hospital of Patras, 26504 Rio Greece Tel:+302610999582
Email: [email protected]
ACCEPTED MANUSCRIPT ABSTRACT Brucellosis is a common zoonotic infection in many parts of the world including the areas around the Mediterranean. Neurobrucellosis represents an uncommon site in <5% of cases. Diagnosis is based on high clinical suspicion, as well as a combination of complex serologic testing
and
abnormal cranial imaging.
Unfortunately,
real-word
settings
often
lack
sophisticated diagnostic modalities, while stringent budget does not allow for repeated
PT
confirmatory testing with alternative methods. In response to the recent article by Erdem et al reporting the presence of diffuse inflammation in MRI, in approximately 45% of patients
RI
with neurobrucellosis, we hereby report our experience with 8 patients presenting with neurobrucellosis in an endemic area, whose diagnosis and management was successfully
SC
driven by common agglutination tests and neglected Rose Bengal test (RBT) in serum and CSF. The authors argue that even though these methods have raised concerns upon their
NU
sensitivity and specificity – currently being surpassed by more complex methodology including ELISA or PCR -, , in resource-limited settings that burden of the disease in high,
MA
re-introduction and simple modification of cheap, non-complex methods like RBT could suffice. Complementary methods should be employed if and where available.
ED
KEY WORDS
AC C
EP T
Neurobrucellosis; Rose Bengal; Wright; Serum Agglutination Test;
ACCEPTED MANUSCRIPT Dear Editor, We read with great interest the recent article by Gündüz et al reporting isolated spinal cord involvement in a case of neurobrucellosis with normal MRI findings (1). Although neurobrucellosis is rare it should be considered in patients with obscure neurologic manifestations in endemic settings (2), even when MRI is negative (1). When positive, MRI findings are non-specific but suggestive of central nervous system disease, showing presence
PT
of diffuse inflammation in a significant number of patients, while inflammatory findings seem to be associated with the duration of symptoms, presence of polyneuropathy and
RI
radiculopathy, high CSF protein level, and low CSF/serum glucose rate. (3) While cranial imaging can be very helpful, in the era of stringent budget, one must consider the difficulty to
SC
employ diagnostic modalities such as MRI in resource limited settings and the need to turn to cheaper modalities. Hence; in response, we present our experience with 8 patients, presenting
NU
with signs of meningoencephalitis finally diagnosed with neurobrucellosis in an endemic area, where diagnosis and treatment was driven by serum agglutination test (SAT) and Rose
MA
Bengal Test (RBT) in cerebrospinal fluid (CSF).
Between 2007-2013, 75 new cases of brucellosis were admitted in a secondary medical
care
unit
of
Western
Greece.
Eight
cases
presented
with
signs
ED
meningoencephalitis as this confirmed by clinical presentation and CSF findings.
of Rose
Bengal test (by Dialab®) , SAT (by Fortress diagnostics), conventional CSF and blood
EP T
culture was utilized for diagnosis and follow-up. Unfortunately, at the time, no SAT or RBT titre quantification in CSF, or further diagnostic testing with MRI, ELISA, PCR, Coombs or immunocapture agglutination test was available to be carried out in our – and several other
AC C
secondary medical care – unit(s).
All patients were positive for epidemiologic history and
SAT titres were >1/160. Patient characteristics and laboratory findings are reported in Table 1. Upon diagnosis, all patients received a combination 6-week regimen of doxycycline (100mg twice daily, orally) and rifampicin (600-900mg daily per os, one morning dose), as per international recommendations, with favorable outcomes (4). No relapse of the disease or any residual complications were observed in any of the 8 diagnosed patients, during a oneyear follow-up period while SAT titers gradually diminished and RBT finally disappeared at various time during patients’ 6-week treatment. Brucellosis is a common zoonotic infection in many parts of the world including the areas around the Mediterranean. Neurobrucellosis may develop at any stage of disease and
ACCEPTED MANUSCRIPT presents
with
widely
variable
manifestations,
including
meningoencephalitis,
myelitis,
radiculitis, cranial and peripheral neuropathies, psychiatric manifestations and subarachnoid haemorrhage. Even though, mortality remains low upon prompt diagnosis and antibiotic treatment, survivors commonly suffer permanent complications.(5, 6) Reported incidence may vary, depending on diagnostic facilities and definition of neurobrucellosis, ranging between 3 and 11% in various series (7). However, diagnostic criteria remain problematic and diagnosis is mostly based on a combination of clinical suspicion, serologic markers and
PT
radiologic findings (7), especially in view of increasing introduction of more sophisticated diagnostic modalities. We hereby presented 8 cases of neurobrucellosis in an endemic setting
RI
that diagnostic modalities are scarce, managing dozens cases of brucellosis yearly. All of our
positive CSF-RBT
SC
8 patients were positive for epidemiologic history, hence a serum SAT titre of >1/160 and in combination with clinical manifestations was considered suggestive of
diagnosis
of infectious
diseases,
it
has
NU
neurobrucellosis (7). Although, positive bacterial culture is the reference standard for been
demonstrated
to
be suboptimal in
neurobrucellosis (8). It was no surprise that in only 12.5% of patients, gram negative bacteria
MA
were isolated, both in blood and CSF; frequency similar to previous reports (7). For this reason, numerous practical serological tests including SAT have been utilized and been Even though their sensitivity remains suboptimal in the
ED
robust in the diagnosis of brucellosis.
diagnosis of neurobrucellosis, in resource limited settings they are the only diagnostic modality available while even so, blood serology remains far more sensitive than other
EP T
methods in the diagnosis of CNS involvement (8, 9). However, agglutination reactions at neutral pH have been shown to be prone to false-negative results, due to prozones and blocking and non-agglutinating antibodies, two problems largely solved by carrying the
AC C
agglutinations at acid pH, as in RBT and Brucellacapt (10). RBT has been a simple screening method for the diagnosis of brucellosis however, concerns have been expressed as to its low sensitivity in chronic cases (11) and low specificity in endemic areas (12, 13), fact that has limited its use in view of current more accurate methods (14). This argument might be true in presence and availability of diagnostically more robust tests in well-equipped laboratories and low prevalence areas. However, in our setting, RBT proved to be more sensitive than conventional cultures while RBT positivity did not seem to correlate with serum SAT titres, as also previously noted (8). As Erdem et al have recently shown, although SAT should be preferred over RBT in CSF in probable neurobrucellosis, RBT was not as weak as expected in a retrospective multicentre
ACCEPTED MANUSCRIPT study of 177 cases (8). Similarly in our case series a sensitivity of 100% in CSF-RBT was observed. Even though this discrepancy could be attributed to low number of cases in this report, a number of reasons, including the quality of antigen provided by each manufacturer as well as, interpretation of the test by different users in different settings of short or long evolution, can also be held responsible (10). Even though, CSF-RBT positivity seemed to correlate well between CSF-SAT titres above a certain threshold (>1/40), cases of CSF-SAT negativity with positive CSF-RBT have been recorded (8), suggesting its potential role in
PT
neurobrucellosis diagnosis. Despite concerns relating to discordant results, recent data have come to show that when modified to test serum dilutions, RBT can reach a sensitivity of patients) and
specificity of 100% (contacts), not requiring further
RI
87.4% (infected
SC
confirmation with other more expensive or time-consuming tests (10, 15). In the experience of these authors, neglected RBT can prove a very useful test for the
NU
diagnosis of neurobrucellosis. It needs no sophisticated training or complicated infrastructure, it is extremely cheap, highly sensitive and easily adaptable to test serum dilutions. It should
MA
be re-introduced in the diagnostic armamentarium of neurobrucellosis, in settings where diagnostic modalities such as MRI or PCR remain – or have become – limited, and
AC C
EP T
ED
complemented with other tests where those available.
ACCEPTED MANUSCRIPT REFERENCES 1.
Gunduz T, Tekturk PT, Yapici Z, Kurtuncu M, Somer A, Torun SH, et al.
Characteristics of isolated spinal cord involvement in neurobrucellosis with no corresponding MRI activity: A case report and review of the literature. Journal of the neurological sciences. 2017;372:305-6. 2.
Erdem H, Inan A, Guven E, Hargreaves S, Larsen L, Shehata G, et al. The burden and
PT
epidemiology of community-acquired central nervous system infections: a multinational study. European journal of clinical microbiology & infectious diseases : official publication
3.
RI
of the European Society of Clinical Microbiology. 2017.
Erdem H, Senbayrak S, Meric K, Batirel A, Karahocagil MK, Hasbun R, et al. Cranial
SC
imaging findings in neurobrucellosis: results of Istanbul-3 study. Infection. 2016;44(5):62331.
Ariza J, Bosilkovski M, Cascio A, Colmenero JD, Corbel MJ, Falagas ME, et al.
NU
4.
Perspectives for the treatment of brucellosis in the 21st century: the Ioannina
5.
MA
recommendations. PLoS medicine. 2007;4(12):e317.
Gul HC, Erdem H, Bek S. Overview of neurobrucellosis: a pooled analysis of 187
cases. International journal of infectious diseases : IJID : official publication of the
6.
ED
International Society for Infectious Diseases. 2009;13(6):e339-43. Erdem H, Ulu-Kilic A, Kilic S, Karahocagil M, Shehata G, Eren-Tulek N, et al.
EP T
Efficacy and tolerability of antibiotic combinations in neurobrucellosis: results of the Istanbul study. Antimicrobial agents and chemotherapy. 2012;56(3):1523-8. 7.
Guven T, Ugurlu K, Ergonul O, Celikbas AK, Gok SE, Comoglu S, et al.
AC C
Neurobrucellosis: clinical and diagnostic features. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America. 2013;56(10):1407-12. 8.
Erdem H, Kilic S, Sener B, Acikel C, Alp E, Karahocagil M, et al. Diagnosis of
chronic brucellar meningitis and meningoencephalitis: the results of the Istanbul-2 study. Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases. 2013;19(2):E80-6. 9.
Araj GF. Update on laboratory diagnosis of human brucellosis. International journal
of antimicrobial agents. 2010;36 Suppl 1:S12-7. 10.
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seven tests for diagnosis of human brucellosis in an area where the disease is endemic. Clinical and vaccine immunology : CVI. 2008;15(6):1031-3. Mantur BG, Amarnath SK, Patil GA, Desai AS. Clinical utility of a quantitative Rose
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Clinical laboratory. 2014;60(4):533-41.
ACCEPTED MANUSCRIPT CONFLICT OF INTEREST STATEMENT On behalf of all authors, the corresponding author states that there is no conflict of interest. ETHICAL STATEMENT Written informed consent was obtained from the patients for publication of their cases.
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Copies are available to review by the Editor of this journal
ACCEPTED MANUSCRIPT Table 1. Summary of Clinical and Laboratory findings. 1
2
3
4
5
6
7
8
Age/Sex
28/M
35/M
38/M
23/M
60/M
44/F
33/M
61/M
Diagnosi
Mening
Meningo
Mening
Mening
Mening
Mening
Mening
Mening
s
o
encephalit
o
o
o
o
o
o
Patient No
encephal encephal encephal encephal encephal encephal
itis
itis
itis
itis
Clinical
Fever,
Fever,
Fever,
Fever,
Fever,
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encephal is
Fever,
Meningi
Fever,
Presenta
meningi
meningis
meningi
meningi
meningi
night
sm,
sweats,
tion
sm
m,
sm,
sm
sm
sweats,
night
meningi
myalgia
myalgias,
myalgia
fatigue
fatigue
fatigue
sweats,
sm,
s,
fatigue,
s,
lethargy
depressi
fatigue
arthralgi
anorexia
disorienta
, fatigue
tion
Blood
Negativ
Positive
Culture
e
Serum
+1/1280
itis
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itis
on
as
Negativ
Negativ
Negativ
Negativ
Negativ
Negativ
e
e
e
e
e
e
+1/640
+1/640
+1/320
+1/320
+1/160-
+(1/160-
ED
+1/320
itis
1/320
1/10240
SAT
)
Serum
(+)
RBT
positive
EP T
titres (Wright)
(+)
(+)
(+)
(+)
(+)
(+)
positive
positive
positive
positive
positive
positive
positive
4.8
40.8
26
36
30
40
3.9
32
CSF cell
30
898
100
15
50
12
445
9 (68%)
count/μl
(80%)
(76%)
(73%)
(100%)
(78%)
(91%)
(93%)
CSF /plasma Glucose
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ratio %
(%Lymp h)
70.2
135.5
92.4
12
84
72
90.7
19.4
CSF
Negativ
Positive
Negativ
Negativ
Negativ
Negativ
Negativ
Negativ
Culture
e
e
e
e
e
e
e
CSF
(+)
(+)
(+)
(+)
(+)
(+)
(+)
(+)
RBT
positive
positive
positive
positive
positive
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ACCEPTED MANUSCRIPT CSF protein (mg/dl) {15-60}
positive
positive
positive
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M:male;F:female; SAT: serum agglutination test; RBT: Rose Bengal Test; CSF: Cerebrospinal
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fluid
ACCEPTED MANUSCRIPT HIGHLIGHTS
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Diagnosis of neurobrucellosis is problematic in resource-limited endemic settings Rose-Bengal test (RBT) represents a cheap, easy method for the diagnosis of brucellosis RBT has been neglected in view of more accurate diagnostic tests When modified to serum dilutions RBT has a sensitivity of 87.4% and specificity of 100%
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