Detection of antibodies to Brucella cytoplasmic proteins in the cerebrospinal fluid of patients with neurobrucellosis

The effect of Brucella abortus on glial activation and cell death in adult male rat's hippocampus

A zoonotic disease called brucellosis can cause flu-like symptoms and heart inflammation. The bacteria responsible for this disease can also enter the brain, causing a condition called neurobrucellosis that can result in long-term neurological problems. In this study, researchers aimed to determine the changes in the hippocampal cells of rats infected with Brucella. For the study, 24 adult male albino rats were inoculated with 1 × 106 CFU Brucella abortus 544. The rats were then deeply anesthetized, and their hippocampus samples were taken for stereological, histological, and molecular studies. The results showed that the infected rats had increased microgliosis and astrogliosis. Furthermore, a high level of caspase-3 in their hippocampal tissue indicated their susceptibility to apoptosis. Additionally, there was a decrease in expression of Ki67, which further supported this. Sholl's analysis confirmed a significant failure in glial morphology. The study demonstrated that the pathogen has the ability to destroy the hippocampus and potentially affect its normal physiology. However, more research is needed to clarify various aspects of neurobrucellosis.

A case of brucellosis-induced Guillain–Barre syndrome

Background

Guillain–Barre syndrome (GBS) is a rare neurological complication of brucellosis, and neurobrucellosis is the most common, but they have many similarities in clinical manifestations. Many clinicians are accustomed to merely explaining the manifestations of nervous system involvement with neurobrucellosis, but they ignore the possibility of GBS, and this leads to misdiagnosis, untimely treatment, and serious consequences.

Case presentation

A 55-year-old male patient was admitted to The First Affiliated Hospital of Harbin Medical University for intermittent fever, fatigue, and waist pain more than three months. Brucellosis was diagnosed from the blood test. Although anti-brucella treatment was given at the time of diagnosis, the disease continued to progress. At the time of the cerebrospinal fluid systematic physical examination and the neuroelectrophysiological test, acute motor sensory axonal neuropathy was diagnosed. The patient was given immediately administered immunoglobulin therapy. After three months of systemic treatment, the patient's muscle strength of the distal limbs gradually recovered. The numbness of the limbs eased slowly, and urination function and respiratory function returned to normal. He could sit by himself.

Conclusions

The possibility of GBS should be closely monitored for when a brucellosis patient shows typical clinical manifestations of progressive muscle weakness, protein-cell separation of the cerebral spinal fluid, and typical demyelinating sensorimotor polyneuropathy.

Seronegative neurobrucellosis-do we need new neurobrucellosis criteria?

Neurobrucellosis presents in various clinical forms and should always be considered in neurological patients in highly endemic areas such as the Mediterranean basin. Establishing a diagnosis can be challenging since serological testing can sometimes yield negative results. We present a rare case of a seronegative relapse of neurobrucellosis in a patient who had been successfully treated for systemic brucellosis. Oligoclonal bands, an agglutination test, and 16S rRNA sequencing of cerebrospinal fluid proved essential in unmasking a confined central nervous system relapse. This case reinforces the need for establishing diagnostic criteria for neurobrucellosis, which could potentially include oligoclonal bands and an agglutination test on the cerebrospinal fluid.

Subarachnoid hemorrhage secondary to Brucella-induced cerebral aneurysm: a case report

BACKGROUND

Brucellosis is a common zoonotic disease that is prevalent in many areas worldwide. This infectious disease can occasionally affect the central nervous system but intracranial arteries are rarely involved.

CASE PRESENTATION

A 17-year-old female who had a history of recurrent fever for 1 month was admitted for subarachnoid hemorrhage due to cerebral aneurysm rupture. Surgery was performed to fix the aneurysm, but the patient had persistent fever after the surgery. Cerebrospinal fluid testing showed a high white blood cell count and elevated protein level but no pathogen was identified in the first two tests. Brucella melitensis was identified in the third cerebrospinal fluid culture, and a diagnosis of brucellosis was finally rendered. The patient was subsequently treated with anti-Brucella medications and her symptoms improved significantly at the last follow-up.

CONCLUSION

Although extremely rare, Brucella-induced cerebral aneurysms can occur and this should be considered in the differential diagnosis of cerebrovascular accidents, especially in Brucella epidemic areas.

Brucellosis

Brucellosis is a common Zoonosis affecting half a million people annually. The most common mode of infection is by consuming unpasteurized milk or milk products. The general manifestations are those of fever with generalized symptoms. The nervous system is affected in 4-7% of cases. The manifestations are protean and include meningo-encephalitis as well as peripheral nervous system involvement. The diagnosis relies on culture, which is cumbersome and can be falsely negative. Agglutination tests for the various species of the organism are the mainstay for diagnosis. Treatment is for 3-6 months with combination therapy including Doxycycline, Rifampicin and ceftriaxone. The main issue is prevention and better animal husbandry.

Case Report: Neurobrucellosis with Plastered Spinal Arachnoiditis: A Magnetic Resonance Imaging-Based Report

Diffuse spinal arachnoiditis in neurobrucellosis is a rare manifestation. We report a boy aged 17, presenting with hearing impairment and recurrent vomiting for 18 months, weight loss for 12 months, dysphagia, dysarthria, hypophonia for 6 months, and gait unsteadiness for 5 months. He had bilateral 5th (motor) to 12th cranial nerve palsy, wasting and weakness of limbs, fasciculations, absent tendon reflexes, and positive Babinski's sign. Cerebrospinal fluid (CSF) showed raised protein and pleocytosis. Magnetic resonance imaging (MRI) showed extensive enhancing exudates in cisterns and post-contrast enhancement of bilateral 5th, 6th, 7th, and 8th nerves. Spine showed clumping with contrast enhancement of the cauda equina roots and encasement of the cord with exudates. Serum and CSF were positive for anti-Brucella antibodies. He showed significant improvement with antibiotics. At 4 months follow-up, MRI demonstrated near complete resolution of cranial and spinal arachnoiditis. It is important to recognize such rare atypical presentations of neurobrucellosis.

Neurobrucellosis

PURPOSE

Neurobrucellosis (NB) is a rare complication of brucellosis. NB presents with avariety of clinical manifestations, and the symptoms are always atypical. Our aim was to analyze the demographic characteristics, clinical manifestations, laboratory findings, imaging findings, treatments and outcomes of patients with NB.

MATERIAL AND METHOD

We retrospectively reviewed the data from 17 patients with NB hospitalized at the Chinese People's Liberation Army General Hospital between 1 January 2005 and 31 October 2016.

RESULTS

The following symptoms were recorded: 10/17 (59%) patients had fever, and 9/17 (53%) patients had a disorder affecting urination and defecation. Involvement of the cranial nerves was documented in 12/17 (71%) patients. The positivity rates of the tests were as follows: serum standard tube agglutination (STA), 15/17 (88.2%); cerebrospinal fluid STA, 10/17 (59%). The radiologic findings were categorized into four types: normal, white matter changes, vascular insult and inflammatory changes. Patients were treated with different combinations of rifampicin, doxycycline, ceftriaxone sodium and sulphamethoxazole for a total of six months. Two (12%) patients deteriorated, and two (12%) patients were lost to follow-up. The remaining patients (76%) were cured, but sequelae occurred in six patients.

CONCLUSIONS

NB should be kept in mind in patients with autonomic dysfunction, especially disorders of urination and defecation. Hearing loss due to vestibulocochlear nerve injury seems to be typical for NB. The high incidence of sequelae may be related to a long disease course and the involvement of the central nervous system. Early detection, diagnosis and treatment could decrease mortality and sequelae.

Cerebrospinal fluid cytology in nonmalignant aseptic meningeal disorders

Cerebrospinal fluid cytology examination is a common and reliable primary and/or complementary procedure for the diagnosis of central nervous system (CNS) disorders. This review provides an update of aseptic meningeal disorders that may be encountered in cytopathology practice. The article covers the cytological findings and helpful ancillary studies needed of nonmalignant aseptic CNS disorders such as viral, bacterial, fungal and parasitic infections, and other noninfectious diseases, such as Mollaret's meningitis (recurrent benign lymphocytic meningitis), Guillain-Barré syndrome, multiple Sclerosis, subarachnoid haemorrhage, and drug-induced disorders.

Glial Cell-Elicited Activation of Brain Microvasculature in Response to Brucella abortus Infection Requires ASC Inflammasome-Dependent IL-1β Production

Blood-brain barrier activation and/or dysfunction are a common feature of human neurobrucellosis, but the underlying pathogenic mechanisms are largely unknown. In this article, we describe an immune mechanism for inflammatory activation of human brain microvascular endothelial cells (HBMEC) in response to infection with Brucella abortus Infection of HBMEC with B. abortus induced the secretion of IL-6, IL-8, and MCP-1, and the upregulation of CD54 (ICAM-1), consistent with a state of activation. Culture supernatants (CS) from glial cells (astrocytes and microglia) infected with B. abortus also induced activation of HBMEC, but to a greater extent. Although B. abortus-infected glial cells secreted IL-1β and TNF-α, activation of HBMEC was dependent on IL-1β because CS from B. abortus-infected astrocytes and microglia deficient in caspase-1 and apoptosis-associated speck-like protein containing a CARD failed to induce HBMEC activation. Consistently, treatment of CS with neutralizing anti-IL-1β inhibited HBMEC activation. Both absent in melanoma 2 and Nod-like receptor containing a pyrin domain 3 are partially required for caspase-1 activation and IL-1β secretion, suggesting that multiple apoptosis-associated speck-like protein containing CARD-dependent inflammasomes contribute to IL-1β-induced activation of the brain microvasculature. Inflammasome-mediated IL-1β secretion in glial cells depends on TLR2 and MyD88 adapter-like/TIRAP. Finally, neutrophil and monocyte migration across HBMEC monolayers was increased by CS from Brucella-infected glial cells in an IL-1β-dependent fashion, and the infiltration of neutrophils into the brain parenchyma upon intracranial injection of B. abortus was diminished in the absence of Nod-like receptor containing a pyrin domain 3 and absent in melanoma 2. Our results indicate that innate immunity of the CNS set in motion by B. abortus contributes to the activation of the blood-brain barrier in neurobrucellosis and IL-1β mediates this phenomenon.

Brucella abortus induces TNF-α-dependent astroglial MMP-9 secretion through mitogen-activated protein kinases

Background

Central nervous system (CNS) invasion by bacteria of the genus Brucella results in an inflammatory disorder called neurobrucellosis. We have recently demonstrated that B. abortus infects microglia and astrocytes, eliciting the production of a variety of pro-inflammatory cytokines which contribute to CNS damage. Matrix metalloproteinases (MMP) have been implicated in inflammatory tissue destruction in a range of pathological situations in the CNS. Increased MMP secretion is induced by pro-inflammatory cytokines in a variety of CNS diseases characterized by tissue-destructive pathology.

Methods

In this study, the molecular mechanisms that regulate MMP secretion from Brucella-infected astrocytes in vitro were investigated. MMP-9 was evaluated in culture supernatants by ELISA, zymography and gelatinolytic activity. Involvement of mitogen-activated protein kinases (MAPK) signaling pathways was evaluated by Western blot and using specific inhibitors. The role of TNF-α was evaluated by ELISA and by assays with neutralizing antibodies.

Results

B. abortus infection induced the secretion of MMP-9 from murine astrocytes in a dose-dependent fashion. The phenomenon was independent of bacterial viability and was recapitulated by L-Omp19, a B. abortus lipoprotein model, but not its LPS. B. abortus and L-Omp19 readily activated p38 and Erk1/2 MAPK, thus enlisting these pathways among the kinase pathways that the bacteria may address as they invade astrocytes. Inhibition of p38 or Erk1/2 significantly diminished MMP-9 secretion, and totally abrogated production of this MMP when both MAPK pathways were inhibited simultaneously. A concomitant abrogation of B. abortus- and L-Omp19-induced TNF-α production was observed when p38 and Erk1/2 pathways were inhibited, indicating that TNF-α could be implicated in MMP-9 secretion. MMP-9 secretion induced by B. abortus or L-Omp19 was completely abrogated when experiments were conducted in the presence of a TNF-α neutralizing antibody. MMP-9 activity was detected in cerebrospinal fluid (CSF) samples from patients suffering from neurobrucellosis.

Conclusions

Our results indicate that the inflammatory response elicited by B. abortus in astrocytes would lead to the production of MMP-9 and that MAPK may play a role in this phenomenon. MAPK inhibition may thus be considered as a strategy to control inflammation and CNS damage in neurobrucellosis.

Neurobrucellosis associated with syndrome of inappropriate antidiuretic hormone with resultant diabetes insipidus and hypothyroidism

Neurological involvement of the central nervous system in brucellosis is uncommon. We describe a rare case of meningoencephalitis due to Brucella melitensis infection, associated with the syndrome of inappropriate antidiuretic hormone secretion and leading to diabetes insipidus and hypothyroidism. Neurobrucellosis, although rare, should be considered in cases of neurological disease of unknown etiology.

Human brucellosis

Human brucellosis still presents scientists and clinicians with several challenges, such as the understanding of pathogenic mechanisms of Brucella spp, the identification of markers for disease severity, progression, and treatment response, and the development of improved treatment regimens. Molecular studies have shed new light on the pathogenesis of Brucella spp, and new technologies have permitted the development of diagnostic tools that will be useful in developing countries, where brucellosis is still a very common but often neglected disease. However, further studies are needed to establish optimum treatment regimens and local and international control programmes. This Review summarises current knowledge of the pathogenic mechanisms, new diagnostic advances, therapeutic options, and the situation of developing countries in regard to human brucellosis.

Management of neurobrucellosis: an assessment of 11 cases

OBJECTIVE

The central nervous system involvement of Brucellosis causes a hard to treat infection with multiple sequelae. The aim of this paper is to discuss the course of neurobrucellosis in response to therapy.

PATIENTS AND METHODS

Patients with neurobrucellosis were evaluated. The diagnosis was established by the isolation of bacteria, abnormal CSF findings and positive serology. Ceftriaxone, rifampicin, doxycycline and trimethoprim sulfamethoxazole were the antibiotic choices for these cases.

RESULTS

We present 11 cases with neurobrucellosis. None of our patients died, albeit one case has a critical situation due to subarachnoid hemorrhage and its' concordant sequelae. Only one of four patients with walking difficulty and two with hearing loss were normalized with therapy. Imaging techniques did not provide any specific contribution regarding the Brucella infection.

CONCLUSIONS

Parenteral ceftriaxone should be used as an initial alternative in the management of neurobrucellosis. Although the therapy should be individualized, the duration of therapy should be a minimum of six months with suitable antibiotics.

Magnetic resonance spectroscopy features of normal-appearing white matter in patients with acute brucellosis

We aimed to evaluate whether the subtle metabolic cerebral changes are present in normal-appearing white matter on conventional MRI, in patients with acute brucellosis, by using MR spectroscopy (MRS). Sixteen patients with acute brucellosis and 13 healthy control subjects were investigated with conventional MRI and single-voxel MRS. Voxels were placed in normal-appearing parietal white matter (NAPWM). N-Acetyl aspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were calculated. There was no significant difference between the study subjects and the control group in NAA/Cr ratios obtained from NAPWM. However, the Cho/Cr ratios were significantly higher in patients with acute brucellosis compared to controls (p=0.01). MRS revealed metabolic changes in normal-appearing white matter of patients with brucellosis. Brucellosis may cause subtle cerebral alterations, which may only be discernible with MRS. Increased Cho/Cr ratio possibly represents an initial phase of inflammation and/or demyelination process of brucellosis.

Evaluation of the PANBIO Brucella immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays for diagnosis of human brucellosis

PANBIO Brucella immunoglobulin G (IgG) and IgM enzyme-linked immunosorbent assays (ELISAs) were assessed against Brucella standard agglutination tube and Coombs tests. The sensitivities of ELISA IgG and IgM were 91% and 100%, respectively, while the specificity was 100% for both. These ELISAs are simple, rapid, and reliable for the diagnosis of human brucellosis.

Utility of an immunocapture-agglutination test and an enzyme-linked immunosorbent assay test against cytosolic proteins from Brucella melitensis B115 in the diagnosis and follow-up of human acute brucellosis

The utility of an immunocapture-agglutination (Brucellacapt, Vircell SL, Granada, Spain) test and an enzyme-linked immunosorbent assay IgG, IgA, and IgM (ELISA-IgG, ELISA-IgA, ELISA-IgM) against cytosolic proteins from Brucella melitensis B115 (R) was compared with ELISA-IgG, ELISA-IgA, and ELISA-IgM against smooth lipopolysaccharide (S-LPS) from B. melitensis 16M (S), serum agglutination test (SAT), and Coombs test in the diagnosis and follow-up for 10 months of 51 patients with acute brucellosis. The sensitivities of ELISA tests against cytosolic proteins varied from 49.0 % for ELISA-IgG to 64.7% for ELISA-IgM and were lower than the sensitivities showed by ELISA S-LPS (from 88.2% to 92.2%), SAT (88.2%), Coombs (96.1%), and Brucellacapt (98.0%) tests. Specificity was over 93% in all cases. The evolutionary behavior of the SAT, Coombs, and Brucellacapt tests was similar. There was a decrease of between 20% and 40% in antibody titer in the 10th month of evolution after treatment. The evolutional curves of IgG, IgA, and IgM against cytosolic protein increased slightly till the eighth month. The specific IgM and IgA antibodies against protein fractions began to show a drop from the eighth month on, showing levels slightly lower than the initial sera values by the end of the 10th month. In this month, titers of specific IgG against proteins fractions remained higher than the titers showed by the initial sera.

Immunoproteomic characterization of Brucella abortus 1119-3 preparations used for the serodiagnosis of Brucella infections

The diagnosis of brucellosis is mainly based on the detection of anti-LPS antibodies. Due to substantial similarity of the O-polysaccharide of Brucella LPS to that of various other Gram-negative bacteria, serological tests of samples containing high amounts of LPS lack specificity. Hence, the development of assays based on more specific protein antigens is an essential subject in brucellosis research. The aim of this study was proteomic characterization of various antigen preparations of the diagnostic reference strain Brucella abortus 1119-3 and the identification of immunogenic proteins suitable for serological assays. Seventeen out of 383 protein spots of B. abortus 1119-3 were identified to be immunogenic by 2-D immunoblotting. These immunogenic spots were assigned to 6 proteins by MALDI-MS and nLC-ESI-MS/MS: Cu-Zn SOD, BCSP31, L7/L12, GroEL, GroES, and DnaK. All immunogenic proteins were present in three different antigen preparations investigated, i.e. native antigen, standard agglutination and commercially available agglutination antigen. 2-D immunoblotting of bacteria cross-reacting with Brucellae in agglutination tests proved that cross-reactivity of proteins is negligible. Surface enhanced laser desorption/ionization mass spectrometry (SELDI-MS) spectra also differentiated B. abortus clearly from cross-reacting bacteria. The combination of SELDI-MS analysis with the specificity of antibody binding will improve the identification of Brucella specific immunogenic proteins.

Chronic meningitis

Chronic meningitis is a syndrome commonly defined by the presence of continuously persistent meningeal inflammation for at least 4 weeks. Presenting neurologic features are often nonspecific, and the list of differential diagnoses is broad. Despite the development of modern molecular diagnostic methods, establishing a specific cause may challenge the acumen of the treating neurologist with clues to the diagnosis residing outside the nervous system and requiring focused investigation. This review discusses selected etiologies illustrating issues in diagnosis and etiologic categories to be considered in the evaluation of this challenging syndrome.

Correlation of antigenic expression with progress in antibiotic therapy of acute human brucellosis

Human brucellosis is a zoonotic disease which is endemic in Saudi Arabia. The aim of this study was to investigate the humoral immune responses and identify the target antigens that persist at different stages in human brucellosis during antibiotic therapy. To do this, an acute case of accidental nosocomial infection was studied experimentally. Blood was collected from the patient at the time of diagnosis, and at weekly intervals during therapy until remission. IgG and IgM immunoblotting was used to characterize specific antigenic determinants, and ELISA antibody titration was performed to quantify the circulating antibodies. Results indicated that protein bands of 12-13.5 kDa bound IgG in the patient's sera but did not bind IgM on immunoblots and are probably not specific for, or important in, early stage infections. However, an 18 kDa band persisted during infection through remission. The pivotal and most important findings were that the number of protein bands seen on immunoblots, the magnitude of ELISA antibody titres and the concomitant changes in the intensity of the polypeptide bands of 42-43 kDa were positively correlated with the stage of infection. High numbers of anti-IgG and -IgM immunoblot bands coupled with high ELISA antibody titres and a concomitant increase in intensity of the 42-43 kDa bands were positively correlated with acute and severe infection. Conversely, a reduction in the number of polypeptide bands as well as a decrease in the intensity, until the complete disappearance of the 42-43 kDa bands, coupled with low (baseline) ELISA antibody titration values indicated successful treatment and remission. The routine use of the methods described here to ascertain the stage of the disease, assess the progress of antimicrobial therapy and monitor cases of relapse in human brucellosis is suggested.

La brucellose à l’aube du 21e siècle

Human brucellosis is now a rare disease in countries where eradication programs (especially vaccination) against brucellosis in cattle, sheep, and goats have been successfully implemented. In France, fewer than 50 brucellosis cases are annually notified to the National Institute for Infection Surveillance. Human brucellosis, however, remains endemic in the Mediterranean basin, Middle East, Western Asia, Africa, and South America. Shortcomings of standard diagnostic methods for brucellosis (variable sensitivity of culture, frequent serological cross reactions) have been only partially resolved by modern molecular biology techniques. There are now 3 new challenges to be faced by the medical and veterinarian community: the expanding wildlife reservoir of brucellosis, with a possible impact on domestic animals; the emergence of Brucella. melitensis infections in cattle, for which prophylactic efficacy of available vaccines has not been established; and recent recognition of a huge animal reservoir of Brucella species in marine mammals, for which the potential virulence in humans remains unknown.

Avaliação de seis testes sorológicos no diagnóstico da brucelose bubalina

Foram examinados 440 soros bubalinos, selecionados em um outro exame de cerca de 1200 amostras sangüíneas. Utilizaram-se seis diferentes testes sorológicos para o exame dessas amostras: dois de aglutinação, dois de ELISA indireto e dois de ELISA competitivo. Os animais positivos no ELISA competitivo da FAO/IAEA foram considerados como infectados, e a comparação com os resultados dos outros testes aconteceu neste sentido. A sensibilidade relativa foi de 100%, 98,57%, 97,14%, 91,42% e 79,28%, e a especificidade relativa de 99,33%, 97,33%, 95,66%, 94,00% e 86,33% nas provas de ELISA competitivo, ELISA indireto com conjugado antibovino de cadeia leve (anticorpo monoclonal com HRPO), ELISA indireto com conjugado contra IgG bovino total, teste do antígeno acidificado tamponado e aglutinação rápida, respectivamente. Discute-se o valor dos diferentes testes sorológicos no diagnóstico da brucelose.