A systematic review and meta-analysis of the prevalence of osteoarticular brucellosis

The relationship between Brucella infection and aortic stiffness in children

OBJECTIVE

In this study, it was aimed to show whether Brucella infection, which causes various cardiovascular complications in children, can lead to an increase in aortic stiffness with a noninvasive method, echocardiography.

METHODS

Children who were diagnosed with Brucella infection and who had tachycardia, chest pain and murmur that were not related to body temperature increase during the treatment were evaluated cardiologically and had echocardiographic examination, were included in the study. Aortic strain, aortic distensibility measurement results and aortic stiffness index of the patients in the patient and control groups were calculated.

RESULTS

Our study included 53 cases with a mean age of 11.43±4.13 years in the patient group and 68 cases with a mean age of 10.16±3.61 years in the control group. We found that systolic blood pressure was lower in the patient group than in the control group (p=0.014). In the analysis of laboratory parameters, blood glucose level was found to be significantly higher in the patient group (p=0.001). In the statistical evaluation of aortic strain, aortic stiffness index and aortic distensibility measurement results between the patient and control groups, no statistically significant difference was found between the groups (p=0.287, p=0.784, p=0.208).

CONCLUSION

In our study, where we tried to show a new parameter that could contribute to the increase in aortic stiffness, the results showed that Brucella infection was not a factor that increased aortic stiffness in the pediatric age group.

Amino Acids Profile in Children with Acute Brucellosis

BACKGROUND

Many new cases of brucella infections are seen in Turkey every year, especially in March, April, and May, due to the consumption of local unpasteurized cheese. Amino acids profiles have not been studied in brucellosis so far.

AIMS

The amino acid profiles may be affected by infectious diseases. Our study aims to evaluate the plasma amino acid profile in the progression of acute brucellosis.

METHODS

Plasma amino acid profile was performed by an 8045 LC-MS / MS device (Shimadzu 8045, Japan) using JASEM amino acid kit.

RESULTS

Analysis of 45 amino acid profiles was made and results profiles showed significant differences in concentrations and types of amino acids in brucella patients. We observed a significant difference in terms of alanine, arginine, aspartic acid, glutamine, glutamic acid, glycine, isoleucine, ornithine, phenylalanine, proline, tyrosine, valine, alpha-aminoadipic acid, alpha-amino-pimelic acid, argininosuccinic acid, gamma-aminobutyric acid, thiaproline, 1-methylhistidine, 3-methylhistidine, hydroxylysine, hydroxyproline, cystine, serotonin, ethanolamine, and taurine (p-value < 0.05 for each). No significant differences were determined regarding asparagine, citrulline, histidine, leucine, alloisoleucine, lysine, methionine, serine, threonine, tryptophan, anserine, alpha aminobutyric acid, beta aminoisobutyric acid, beta-alanine, cystathionine, histamine, and 5-oh-trp (p-value > 0.05 for all).

CONCLUSION

Patients with brucellosis have a specific profile of amino acids which may reflect sequelae of pathological and metabolic biochemical changes in the disease process due to the growth of Brucella spp. in the human body leading to an imbalance of amino acid levels.

Risk perception and preventive behaviors related to brucellosis among Iranian livestock farmers

Background and Aims

Brucellosis is one of the zoonotic diseases that endanger the health of the population, particularly in developing countries. This study aimed to assess risk perception and behaviors of livestock farmers on brucellosis based on PRECEDE model in a rural area in the northwest of Iran.

Methods

This was a cross-sectional study conducted with 365 livestock farmers in rural areas of Germi, Iran. Participants were selected random sampling method. Data were gathered using a PRECEDE model based questionnaire consisted of five sections including demographic characteristics, predisposing factors (knowledge and attitudes), reinforcing factors, enabling factors, and brucellosis preventive behaviors.

Results

The mean ± SD of age of participants was 47.1 ± 14.7 years. The state of knowledge about preventive behaviors and ways of disease transmission was evaluated as appropriate (with 87% and 81% of the maximum score, respectively). Three aspects of attitude in participants were desirable. Predisposing factors including knowledge of prevention ways, knowledge of transmission ways, and attitudes toward prevention, reinforcing factors, as well as education were significant predictors of brucellosis preventive behaviors. R 2 and adjusted R 2 were 0.312 and 0.310, respectively, according to which, about 31% of the changes in the brucellosis preventive behaviors explained by significant dependent variables.

Conclusions

Given that farmers are at particular high risk of exposing brucellosis, improving their knowledge and desirable attitudes of brucellosis is crucial to increasing control the disease.

Follow-up outcomes of asymptomatic brucellosis: a systematic review and meta-analysis

Balancing the potentially serious outcomes of asymptomatic brucellosis and "waiting" for treatment in clinical practice is an urgent issue. Therefore, we assessed the follow-up outcomes and epidemiological characteristics of asymptomatic brucellosis in the absence of treatment to provide evidence-based clinical clues. We searched eight databases in which 3610 studies from 1990 to 2021 were related to the follow-up outcomes of asymptomatic brucellosis. Thirteen studies, involving 107 cases, were finally included. Regarding the follow-up outcomes, we examined the presence or absence of symptoms and decreased serum agglutination test (SAT) titre. During the 0.5-18 months follow-up period, the pooled prevalence of appearing symptomatic was 15.4% (95% CI 2.1%-34.3%), cases that remained asymptomatic were 40.3% (95% CI 16.6%-65.8%), and decreased SAT titre was observed in 36.5% (95% CI 11.6%-66.1%). Subgroup analysis indicated that the pooled prevalence of appearing symptomatic with follow-up times of less than 6 months, 6-12 months, and 12-18 months was 11.5%, 26.4%, and 47.6%, respectively. The student subgroup had a higher prevalence of symptoms (46.6%) than the occupational and family populations. In conclusion, asymptomatic brucellosis has a high likelihood of appearing symptomatic and its severity may be underestimated. Active screening of occupational and family populations should be enhanced, and special attention should be paid to high-titre students for early intervention, if necessary. Additionally, future prospective, long-term, and large-sample follow-up studies are essential.

Case Report: Metagenomic Next-Generation Sequencing Confirmed a Case of Spine Infection with Brucella melitensis in Non-Endemic Area

Brucellosis is a zoonotic disease caused by Brucella spp., with the highest prevalence found in the northern cities of China. In this case report, we present an occurrence of spinal infection caused by B. melitensis in a 67-year-old man residing in a non-endemic area of southern China. The patient initially presented with chest and back pain, which was not accurately diagnosed and treated at a local hospital. Subsequently, due to worsening pain, he was admitted to our hospital. To determine the cause of the infection, we performed CT-guided aspiration biopsy and collected biopsy tissue for metagenomic next-generation sequencing (mNGS) on the second day of hospitalization. Imaging investigations revealed involvement of the thoracic vertebrae, specifically thoracic 4-7 with the main focus on 5-6, accompanied by stenosis of the intervertebral space. The mNGS results indicated that the spine infection was caused by B. melitensis. The patient's history as a shepherd and a positive Rose Bengal plate test (RBPT) further supported the diagnosis of brucella spondylitis. In order to alleviate pain and restore spinal function, the patient underwent posterior internal fixation of the thoracic spine. Treatment was initiated with cefoperazone/sulbactam, followed by doxycycline. Subsequently, the patient was switched to a combination therapy of rifampicin and doxycycline for a duration of six weeks. The patient responded well to treatment, and his condition remained stable. In conclusion, brucellosis is a common disease that can be easily misdiagnosed. This case report highlights the potential value of mNGS in early and rapid diagnosis. We believe that mNGS can serve as an effective tool to improve the diagnosis of spine infections caused by this pathogen.

Brucella-infected abdominal aortic aneurysm: management strategies for an uncommon aneurysm

Objective

The occurrence of Brucella-induced abdominal aortic aneurysms is an exceedingly rare phenomenon, yet it stands as one of the most severe complications within this context. The combined utilization of serological testing and imaging diagnostics has been validated as an effective approach for the identification of Brucella-induced abdominal aortic aneurysms. Presently, the predominant therapeutic strategies encompass antibiotic treatment and surgical intervention. Nonetheless, ongoing controversies persist concerning the establishment of diagnostic criteria, the optimal timing and selection of antibiotic regimens, and the nuanced decision between open surgical procedures and endovascular interventions. Through a meticulous analysis of cases originating from our institution as well as a comprehensive review of previously documented instances, we aim to engage in a detailed discourse on the salient diagnostic and therapeutic facets surrounding Brucella-induced abdominal aortic aneurysms.

Methods

We conducted a retrospective summary of three cases involving Brucella-induced abdominal aortic aneurysms treated within our institution. Furthermore, we performed a comprehensive PubMed search, without imposing restrictions on language or publication year, to identify pertinent literature pertaining to Brucella-induced abdominal aortic aneurysms. The selection criteria primarily focused on case reports delineating occurrences of abdominal aortic aneurysms attributed to Brucella infection.

Results

We present three distinct cases of Brucella-induced abdominal aortic aneurysms managed at our institution, providing comprehensive insights into the employed diagnostic and therapeutic approaches. Additionally, over the past five decades, a total of 24 cases in 23 publications of Brucella-induced abdominal aortic aneurysms have been reported on PubMed. The earliest report dates back to 1976.

Conclusion

Our analysis suggests that Brucella-induced abdominal aortic aneurysm is characterized by a remarkably low incidence but is associated with a substantial risk of life-threatening complications. The integration of serological and imaging assessments assumes pivotal importance in facilitating prompt diagnosis of this condition. The prompt initiation of targeted antibiotic therapy is recommended, and the selection of appropriate surgical strategies should be guided by considerations including aneurysm dimensions and morphological attributes. The timely identification and intervention carry utmost significance in retarding disease advancement and ameliorating unfavorable clinical outcomes.

Activation of mucosal immunity as a novel therapeutic strategy for combating brucellosis

Brucellosis is a disease of livestock that is commonly asymptomatic until an abortion occurs. Disease in humans results from contact of infected livestock or consumption of contaminated milk or meat. Brucella zoonosis is primarily caused by one of three species that infect livestock, Bacillus abortus in cattle, B. melitensis in goats and sheep, and B. suis in pigs. To aid in disease prophylaxis, livestock vaccines are available, but are only 70% effective; hence, improved vaccines are needed to mitigate disease, particularly in countries where disease remains pervasive. The absence of knowing which proteins confer complete protection limits development of subunit vaccines. Instead, efforts are focused on developing new and improved live, attenuated Brucella vaccines, since these mimic attributes of wild-type Brucella, and stimulate host immune, particularly T helper 1-type responses, required for protection. In considering their development, the new mutants must address Brucella's defense mechanisms normally active to circumvent host immune detection. Vaccination approaches should also consider mode and route of delivery since disease transmission among livestock and humans is believed to occur via the naso-oropharyngeal tissues. By arming the host's mucosal immune defenses with resident memory T cells (TRMs) and by expanding the sources of IFN-γ, brucellae dissemination from the site of infection to systemic tissues can be prevented. In this review, points of discussion focus on understanding the various immune mechanisms involved in disease progression and which immune players are important in fighting disease.

Contribution to Diagnosis of Magnetic Resonance Imaging and Inflammatory Markers in Musculoskeletal Involvement of Brucellosis

ABSTRACT Objective: Musculoskeletal involvement in brucellosis is very important. This study aimed to evaluate the magnetic resonance imaging (MRI) findings and hematological parameters as a predictive value for the diagnosis of musculoskeletal brucellosis. Methods: This prospective case-control study was conducted between June 2011 and November 2019 in a university hospital. Ninety-nine patients with the confirmed diagnosis of brucellosis without musculoskeletal involvement and forty-three brucellosis patients with musculoskeletal involvement were examined. The hematological, biochemical parameters, and radiological imaging findings of both groups were recorded. These parameters were statistically compared between the two groups. Results: The mean age of the patients (non-involvement group) and musculoskeletal involvement groups was 44.04 ± 23.11 and 37.92 ± 24.80 years, respectively (P = 0.062). C-reactive protein (CRP) and alkaline phosphatase (ALP) levels were significantly higher in the musculoskeletal involvement group (P < 0.05). The lower lymphocyte level was statistically significant in this group. Based on the receiver operating characteristic (ROC) analysis, the sensitivity and specificity were 70% and 65% for ALP, 77% and 58% for CRP, 83% and 45% for lymphopenia, respectively. There was no statistically significant difference between the two groups in terms of the other hematological and biochemical parameters. Spondylodiscitis (34.8%) was the most common MRI finding in patients with musculoskeletal involvement. Conclusions: Our study results show that CRP, ALP, and lymphopenia can be used as valuable markers in the preliminary diagnosis of musculoskeletal brucellosis.

Clinical Features of Human Brucellosis and Risk Factors for Focal Complications: A Retrospective Analysis in a Tertiary-Care Hospital in Beijing, China

Purpose

Brucellosis is an ongoing zoonotic disease in China, but there are few data in Beijing. This study was designed to illustrate clinical characteristics of patients with brucellosis in Beijing, China and explore the risk factors for focal brucellosis.

Patients and Methods

Data of patients with brucellosis were retrospectively collected from the patients’ electronic medical records in Beijing Youan Hospital during 2010 to 2021, including epidemiological, demographic and clinical features. Risk factors for focal brucellosis were identified by multivariable logistic regression models.

Results

A total of 197 patients were included in the study, with 165 (83.8%) cases in acute phase and 32 (16.2%) cases in chronic phase. Patients in acute phase were more likely to have splenomegaly (24.2% vs 3.1%, p=0.007) than those in chronic phase, but had less arthralgia (62.4% vs 81.3%, p=0.040). The median level of alanine aminotransferase (36.9 vs 20.7, p=0.001) was higher in patients at acute stage than those at chronic stage. Of all the patients, 76 (38.6%) were reported with focal complications, including 16 (8.1%) peripheral arthritis, 36 (18.3%) spondylitis, 17 (8.6%) epididymoorchitis, 8 (4.1%) meningitis and 3 (1.3%) endocarditis. Additionally, male (OR 2.76, 95% CI 1.15–6.64, p = 0.023), arthralgia (OR 6.23, 95% CI 2.36–16.43, p < 0.001) and higher level of platelets (OR 1.01, 95% CI 1.00–1.01, p < 0.001) were the independent risk factors for focal brucellosis.

Conclusion

The control of human brucellosis still cannot be ignored due to the re-emerging cases in Beijing, which are more likely to present splenomegaly and abnormal liver function in acute phase. Moreover, male, arthralgia and high level of platelets were the independent risk factors for focal brucellosis.

Seroprevalence and Risk Factors for Brucella Infections in Jordan

Brucellosis is a significant zoonotic disease and is endemic in several regions of the world. This study is aimed to determine the nationwide spatial distribution, seroprevalence, and risk factors for Brucella infections in Jordan. Serum samples of 938 individuals from 11 governorates were tested for Brucella spp. antibodies using Rose Bengal and Brucellacapt® tests. A validated questionnaire was used to collect demographic, animal ownership, and food consumption data. The seroprevalence of Brucella infection in Jordan’s population was 6.7% (95% CI, 5.2–8.5%). The multivariate model showed that location of residence, consuming raw milk/milk products, and owning small ruminants (goat and/or sheep) were significantly associated with seropositivity after controlling for age and gender. Individuals living in the northern Badia region had 8.82 greater odds (95% CI, 4.56–17.03) of seropositivity than individuals living in the Middle region of the country. Individuals who reported consumption of raw milk/milk products had 3.7 higher odds (95% CI, 2.01–6. 81) of seropositivity compared with individuals not consuming raw milk/milk products. In addition, individuals who own small ruminants (goat and/or sheep) had 2.14 higher odds (95% CI, 1.11–4.12) of seropositivity compared with individuals who do not own small ruminants. The identified geographic hotspots and small ruminants’ ownership, risk of raw milk products highlight the need for tailored training, education campaigns, and resources for controlling brucellosis in Jordan.

Facing the Human and Animal Brucellosis Conundrums: The Forgotten Lessons

Brucellosis is a major zoonotic disease caused by Brucella species. Historically, the disease received over fifty names until it was recognized as a single entity, illustrating its protean manifestations and intricacies, traits that generated conundrums that have remained or re-emerged since they were first described. Here, we examine confusions concerning the clinical picture, serological diagnosis, and incidence of human brucellosis. We also discuss knowledge gaps and prevalent confusions about animal brucellosis, including brucellosis control strategies, the so-called confirmatory tests, and assumptions about the primary-binding assays and DNA detection methods. We describe how doubtfully characterized vaccines have failed to control brucellosis and emphasize how the requisites of controlled safety and protection experiments are generally overlooked. Finally, we briefly discuss the experience demonstrating that S19 remains the best cattle vaccine, while RB51 fails to validate its claimed properties (protection, differentiating infected and vaccinated animals (DIVA), and safety), offering a strong argument against its current widespread use. These conundrums show that knowledge dealing with brucellosis is lost, and previous experience is overlooked or misinterpreted, as illustrated in a significant number of misguided meta-analyses. In a global context of intensifying livestock breeding, such recurrent oversights threaten to increase the impact of brucellosis.

Brucella prostatic abscess: a retrospective study of eight cases and a literature review

OBJECTIVE

To present the clinical characteristics, diagnostics, and treatments for Brucella prostatic abscess (BPA).

METHODS

We retrospectively analyzed eight BPA patients according to their vocations, age, clinical manifestations, laboratory test results, magnetic resonance imaging (MRI) findings, and treatments.

RESULTS

The median age was 59 years. The most common clinical symptom was fever, followed by dysuria, erectile dysfunction, frequent urination, and urodynia. C-reactive protein (CRP) concentrations were significantly elevated in all patients, and in all by one patient, the erythrocyte sedimentation rate (ESR) was high. Prostate enlargement occurred in 87.5% of the patients. Lesions were located in the prostate peripheral (87.5%) and central zones (100%), with homogenous signals on T1-weighted imaging (T1WI) and a hyperintense signal on short tau inversion recovery (STIR). Patients had a small nodule or multiple nodules, with slight hyperintense to hyperintense signals on T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI). Three patients had pelvic effusion, and seminal vesicle (37.5%), epididymis (12.5%), and bladder (12.5%) infections occurred. All patients received rifampicin and doxycycline with levofloxacin; all lesions had resolved at follow-up ultrasonography.

CONCLUSION

Even in epidemic areas, the incidence of BPA is relatively rare. Our findings may increase the understanding of BPA and reduce misdiagnosis and mistreatment.

Prevalence and relevant factors of positive RF in brucellosis patients with arthralgia

Background

Brucellosis is a critical zoonotic disease in the world, it is the non-specific arthralgia that make brucellosis patients easily misdiagnosed as rheumatoid arthritis (RA) in endemic regions. Elevated rheumatoid factor (RF) is an essential indicator of RA, and the RF in brucellosis patients is significantly higher than healthy people. Therefore, this study further explored the distribution of RF and the relevant factors of the RF positivity in brucellosis patients with arthralgia, in order to strengthen the recognition of physicians for brucellosis patients with RF positivity, especially in brucellosis-endemic areas, so as to avoid misdiagnosis and untimely treatment that may lead to malignant outcomes.

Methodology and principal findings

The medical records of all 572 brucellosis inpatients were collected in the Sixth People’s Hospital of Shenyang, China from 2015 to 2016. After excluding 106 patients without arthralgia, 5 patients who unwilling to perform RF testing and 16 patients with diseases that may affect RF, 445 brucellosis inpatients with arthralgia were involved in this retrospective cross-sectional study. 143 (32.1%) patients with RF >10 IU/ml were classified into the RF positive group, with an average level of 16.5[12.2, 34.7] IU/ml, of which 45 (10.1%) patients were high-positive with RF >30 IU/ml. Multivariate logistic regression model was used to further analyze the relevant factors of the RF positivity and found that age, wrist joint pain and elevated C-reactive protein (CRP) were positively associated with RF positivity, with OR of 1.02 (P = 0.024), 8.94 (P = 0.008) and 1.79 (P = 0.019), respectively.

Conclusion

The prevalence of positive RF in brucellosis patients with arthralgia was critical, nearly one-third of patients had RF positive. Elderly men brucellosis patients with arthralgia, wrist joint pain and elevated CRP were at high risk of positive RF. It is reminded that physicians should focus on differential diagnosis during clinical diagnosis and treatment, especially in brucellosis-endemic regions.

Brucellosis is a highly contagious zoonosis caused by Brucella spp., which compromises to organs and systems, causing non-specific symptoms such as fever, headache, sweating, fatigue, myalgia and arthralgia. Similarly, patients with rheumatoid arthritis (RA) may also have the above non-specific symptoms. It is precisely because of the non-specificity and similarity of symptoms that brucellosis patients were easily misdiagnosed and failed to receive timely treatment, resulting in neurosis, chronic fatigue syndrome, endocarditis and other adverse outcomes. However, rheumatoid factor (RF) is an essential indicator of RA, and the RF in brucellosis patients is significantly higher than healthy people. In order to strengthen the recognition of physicians for brucellosis patients with RF positivity, we conducted this research and found that the prevalence of positive RF in brucellosis patients with arthralgia was common and critical. Elderly men brucellosis patients with arthralgia, wrist joint pain and elevated CRP were at high risk of positive RF. It is reminded that physicians should pay attention to the possibility of brucellosis during clinical diagnosis and treatment, especially in brucellosis-endemic regions, which had certain clinical significance.

Behavioral and Neurochemical Shifts at the Hippocampus and Frontal Cortex Are Associated to Peripheral Inflammation in Balb/c Mice Infected with Brucella abortus 2308

Brucellosis is a zoonosis affecting 50,000,000 people annually. Most patients progress to a chronic phase of the disease in which neuropsychiatric symptoms upsurge. The biological processes underlying the progression of these symptoms are yet unclear. Peripheral inflammation mounted against Brucella may condition neurochemical shifts and hence unchained neuropsychiatric disorders. Our work aimed at establishing whether neurological, behavioral, and neurochemical disarrays are circumstantially linked to peripheral inflammation uprise secondary to Brucella abortus 2308 infections. We then evaluated, in control and Brucella-infected mice, skeletal muscle strength, movement coordination, and balance and motivation, as well as dopamine, epinephrine, norepinephrine, and serotonin availability in the cerebellum, frontal cortex, and hippocampus. Serum levels of proinflammatory cytokines and corticosterone in vehicle-injected and -infected mice were also estimated. All estimates were gathered at the infection acute and chronic phases. Our results showed that infected mice displayed motor disabilities, muscular weakness, and reduced motivation correlated with neurochemical and peripheral immunological disturbances that tended to decrease after 21 days of infection. The present observations support that disturbed peripheral inflammation and the related neurochemical disruption might lead to mood disorders in infected mice. Future experiments must be aimed at establishing causal links and to explore whether similar concepts might explain neurological and mood disorders in humans affected by brucellosis.

Fever in the Returned Pediatric Traveler

Global mobility has been steadily increasing in recent years. The assessment of the febrile child returning from international travel is a diagnostic challenge. The COVID-19 pandemic has profoundly affected international travel and made evaluation and management of the sick returned traveler more challenging. Children visiting friends and relatives abroad remain at higher risk of infection compared to tourists. This review presents a guidance on the initial assessment of a traveling febrile child including interpretation of medical history, physical examination, and laboratory findings. Important clues to etiology include exposure to different infectious agents, incubation periods of pathogens, and prophylaxis regimens and vaccines received. Early identification of potentially life-threatening and highly contagious infections is essential. In this article, we discuss the epidemiology, evaluation, and management of specific travel related infections such as malaria, typhoid fever, dengue fever, viral hemorrhagic fever, rickettsiosis, leptospirosis, schistosomiasis, gastrointestinal, and respiratory infections.

Adhesive Functions or Pseudogenization of Type Va Autotransporters in Brucella Species

Adhesion to host cells is a key step for successful infection of many bacterial pathogens and may define tropism to different host tissues. To do so, bacteria display adhesins on their surfaces. Brucella is an intracellular pathogen capable of proliferating in a wide variety of cell types. It has been described that BmaC, a large protein that belongs to the classical (type Va) autotransporter family, is required for efficient adhesion of Brucella suis strain 1330 to epithelial cells and fibronectin. Here we show that B. suis 1330 harbors two other type Va autotransporters (BmaA and BmaB), which, although much smaller, share significant sequence similarities with BmaC and contain the essential domains to mediate proper protein translocation to the bacterial surface. Gain and loss of function studies indicated that BmaA, BmaB, and BmaC contribute, to a greater or lesser degree, to adhesion of B. suis 1330 to different cells such as synovial fibroblasts, osteoblasts, trophoblasts, and polarized epithelial cells as well as to extracellular matrix components. It was previously shown that BmaC localizes to a single bacterial pole. Interestingly, we observed here that, similar to BmaC, the BmaB adhesin is localized mostly at a single cell pole, reinforcing the hypothesis that Brucella displays an adhesive pole. Although Brucella species have strikingly similar genomes, they clearly differ in their host preferences. Mainly, the differences identified between species appear to be at loci encoding surface proteins. A careful in silico analysis of the putative type Va autotransporter orthologues from several Brucella strains showed that the bmaB locus from Brucella abortus and both, the bmaA and bmaC loci from Brucella melitensis are pseudogenes in all strains analyzed. Results reported here evidence that all three autotransporters play a role in the adhesion properties of B. suis 1330. However, Brucella spp. exhibit extensive variations in the repertoire of functional adhesins of the classical autotransporter family that can be displayed on the bacterial surface, making them an interesting target for future studies on host preference and tropism.

Evaluation of the safety profile of the vaccine candidate Brucella melitensis 16MΔvjbR strain in goats

Small ruminant brucellosis is caused by the Gram negative cocci-bacillus Brucella (B.) melitensis, the most virulent Brucella species for humans. In goats and sheep, middle to late-term gestation abortion, stillbirths and the delivery of weak infected offspring are the characteristic clinical signs of the disease. Vaccination with the currently available Rev. 1 vaccine is the best option to prevent and control the disease, although it is far from ideal. In this study, we investigate the safety of the B. melitensis 16MΔvjbR strain during a 15-month period beginning at vaccination of young goats, impregnation, delivery and lactation. Forty, 4 to 6 months old, healthy female crossbreed goats were randomly divided into four groups (n = 10) and immunized subcutaneously with a single vaccine dose containing 1x10⁹ CFU of B. melitensis 16MΔvjbR delivered in alginate microcapsules or non-encapsulated. Controls received empty capsules or the commercially available Rev.1 vaccine. Seven months post-vaccination, when animals were sexually mature, all goats were naturally bred using brucellosis-free males, and allowed to carry pregnancies to term. Blood samples to assess the humoral immune response were collected throughout the study. At two months post-delivery, all dams and their offspring were euthanized and a necropsy was performed to collect samples for bacteriology and histology. Interestingly, none of the animals that received the vaccine candidate regardless of the formulation exhibited any clinical signs associated with vaccination nor shed the vaccine strain through saliva, vagina or the milk. Gross and histopathologic changes in all nannies and offspring were unremarkable with no evidence of tissue colonization or vertical transmission to fetuses. Altogether, these data demonstrate that vaccination with the mutant strain 16MΔvjbR is safe for use in the non-pregnant primary host.

Improved Early Detection of Focal Brucellosis Complications with Anti-Brucella IgG

To evaluate the associations of inflammatory factors and serological test results with complicated brucellosis, we recruited 285 patients with a diagnosis of brucellosis between May 2016 and September 2019. The patients were subsequently classified into two groups according to the presence of complications. We collected demographic and clinical information and routine laboratory test results in addition to anti-Brucella IgG and IgM levels. Anti-Brucella IgG and IgM were uniformly tested using enzyme-linked immunosorbent assays (ELISAs) in this study. Among the 285 patients with brucellosis, 111 (38.95%) had complicated brucellosis. Osteoarthritis occurred more often in the subacute and chronic stages than in the acute stage (P = 0.002). Genital infection occurred more frequently in the acute stage than in the other stages (P = 0.023). Fever was not frequently observed in complicated cases (P < 0.001). The erythrocyte sedimentation rate (ESR) and the C-reactive protein (CRP) and anti-Brucella IgM and IgG levels were higher in complicated-brucellosis patients than in uncomplicated-brucellosis patients (P < 0.001). Anti-Brucella IgG, with an area under the curve of 0.885 (95% confidence interval [CI], 0.847 to 0.924), was the most robust indicator of complicated brucellosis. Positive culture, anti-Brucella IgM, the ESR, and CRP could be considered indicators, but their efficacy was weaker than that of IgG. In conclusion, a high ESR, high CRP, high anti-Brucella IgM and IgG levels, and positive culture were indicators of complicated brucellosis; among these, anti-Brucella IgG was the most robust biomarker.

Brucellosis Presenting With Pancytopenia and Foot Drop

Brucellosis is a zoonotic bacterial infection and is highly treatable. Despite being eradicated from most developed countries, its prevalence in Africa, the Middle East and parts of Asia pose a high risk of morbidity if undiagnosed. It mainly affects the reticuloendothelial system and manifests as fever, constitutional symptoms, hepatomegaly, and splenomegaly, but other organ systems can also be involved. Neurobrucellosis is a type of brucellosis in which the central or peripheral nervous systems are affected. It can present with a myriad of signs and symptoms such as stroke, meningitis, and cranial nerve palsies. We present a rare case of a 16-year-old boy with brucellosis who presented with pancytopenia and foot drop. He was subsequently managed with intravenous antibiotics for brucellosis and physiotherapy for foot drop.

Brucellar spondylodiscitis: A case series with focus on histopathological features

Brucellar spondylodiscitis (BS) is the most common form of musculoskeletal brucellosis. The isolation of Brucella spp from blood, other body fluids or tissue cultures is the gold standard for definitive diagnosis of BS. BS shows a large histopathological spectrum of lesions with non-specific and granulomatous forms, and its histopathological features are not widely reported. This case series study reported the histopathological features of a series of 21 BS. Ten cases revealed nonspecific forms of BS. Lymphocytes were the predominant inflammatory cells in this group. In one case neutrophils were predominant. The eleven remaining were granulomatous. The 11 exhibited histiocytic type granulomas. Ten were non-necrotizing. One case, taken from abscess wall, contained minimal deposition of caseous like necrotic material. This case and 2 others corresponding to abscess wall biopsies, showed histiocytic granulomas mixed with small aggregates of epithelioid cells without well-formed epithelioid granuloma nor giant cell. The histopathological diagnosis of BS is challenging. Nonspecific forms of BS, mimiking pyogenic spondylodiscitis, are observed in about half of the cases. Although nonspecific forms of BS are characterized by the predominance of lymphocytes and plasmocytes, BS forms with predominant neutrophil cell infiltration do exist. Histiocytic granuloma is highly suggestive of BS. Purely epithelioid forms of BS were not observed in the present series. Caseous like necrosis suggestive of tuberculosis is a possible feature of BS.

Search trends and prediction of human brucellosis using Baidu index data from 2011 to 2018 in China

Reporting on brucellosis, a relatively rare infectious disease caused by Brucella, is often delayed or incomplete in traditional disease surveillance systems in China. Internet search engine data related to brucellosis can provide an economical and efficient complement to a conventional surveillance system because people tend to seek brucellosis-related health information from Baidu, the largest search engine in China. In this study, brucellosis incidence data reported by the CDC of China and Baidu index data were gathered to evaluate the relationship between them. We applied an autoregressive integrated moving average (ARIMA) model and an ARIMA model with Baidu search index data as the external variable (ARIMAX) to predict the incidence of brucellosis. The two models based on brucellosis incidence data were then compared, and the ARIMAX model performed better in all the measurements we applied. Our results illustrate that Baidu index data can enhance the traditional surveillance system to monitor and predict brucellosis epidemics in China.

Interaction of Brucella abortus with Osteoclasts: a Step toward Understanding Osteoarticular Brucellosis and Vaccine Safety

Osteoarticular disease is a frequent complication of human brucellosis. Vaccination remains a critical component of brucellosis control, but there are currently no vaccines for use in humans, and no in vitro models for assessing the safety of candidate vaccines in reference to the development of bone lesions currently exist. While the effect of Brucella infection on osteoblasts has been extensively evaluated, little is known about the consequences of osteoclast infection. Murine bone marrow-derived macrophages were derived into mature osteoclasts and infected with B. abortus 2308, the vaccine strain S19, and attenuated mutants S19vjbR and B. abortus ΔvirB2 While B. abortus 2308 and S19 replicated inside mature osteoclasts, the attenuated mutants were progressively killed, behavior that mimics infection kinetics in macrophages. Interestingly, B. abortus 2308 impaired the growth of osteoclasts without reducing resorptive activity, while osteoclasts infected with B. abortus S19 and S19vjbR were significantly larger and exhibited enhanced resorption. None of the Brucella strains induced apoptosis or stimulated nitric oxide or lactose dehydrogenase production in mature osteoclasts. Finally, infection of macrophages or osteoclast precursors with B. abortus 2308 resulted in generation of smaller osteoclasts with decreased resorptive activity. Overall, Brucella exhibits similar growth characteristics in mature osteoclasts compared to the primary target cell, the macrophage, but is able to impair the maturation and alter the resorptive capacity of these cells. These results suggest that osteoclasts play an important role in osteoarticular brucellosis and could serve as a useful in vitro model for both analyzing host-pathogen interactions and assessing vaccine safety.

Current therapeutic strategy in osteoarticular brucellosis

Brucellosis is a common zoonotic disease with high morbidity. In the majority of human cases, the causative agent is B. melitensis. Infection is transmitted to humans by direct/indirect contact with the contaminated animal products (e.g., consumption of unpasteurized milk), infectious aerosols and aborted fetus. Brucellosis often affects middle-aged adults and young people. Patients with brucellosis tend to have non-specific symptoms, including fever, chills, night sweats, joint pain and myalgia. Brucellosis affects various organs and tissues. The osteoarticular system is one of the most commonly described affected systems in humans. In several clinical studies, the prevalence of Osteoarticular Brucellosis (OB) is reported as 2-77%. Most important osteoarticular clinical forms osteomyelitis, spondylitis, sacroiliitis, arthritis and bursitis. Spondylitis and spondylodiscitis are the most frequent complications. Spondylodiscitis often affects the lumbar (especially at the L4- L5 levels) and low thoracic vertebrae than the cervical spine. Back pain and sciatica radiculopathy are the most common complaints about patients. Sacroiliitis is associated with severe pain, especially back pain in affected individuals. Spinal destructive brucellar lesions are also reported in adults in previous studies. Brucellosis is diagnosed with clinical inflammatory signs (eg. tenderness, pain) of the affected joints together with positive serological tests and positive blood/synovial fluids cultures. Serological test measures the total amount of IgM/IgG antibodies. Standard agglutination test (SAT) titer ≥1:160 is in favor of brucellosis diagnosis. Enzyme-Linked Immunosorbent Assay (ELISA) and Polymerase chain reaction (PCR) are other types of diagnostic tests. Radiological assessments, such as joint sonography, computed tomography, magnetic resonance imaging, are the most helpful radiological methods to diagnose spinal brucellosis.

The agents commonly used in the treatment of brucella spondylitis are doxycycline, streptomycin, gentamicin, ciprofloxacin, trimethoprim/sulfamethoxazole and rifampicin. The recommended regimens for treatment of brucella involve two or three antibiotics combinations. No standard treatment, physicians prescribe drugs based on conditions of the disease. Patients need a long-term (usually at three months) antibiotic therapy for mainly aiming to prevent relapses. Surgery may be required for patients with spinal abscess. This review focused on physicians’ awareness for osteoarticular involvement, clinical presentation, diagnosis and current treatment of OB.

The NOD-scid IL2rγnull Mouse Model Is Suitable for the Study of Osteoarticular Brucellosis and Vaccine Safety

Osteoarticular brucellosis is the most common complication in Brucella-infected humans regardless of age, sex, or immune status. The mechanism of bone destruction caused by Brucella species remained partially unknown due to the lack of a suitable animal model. Here, to study this complication, we explored the suitability of the use of the NOD-scid IL2rγ^null mouse to study osteoarticular brucellosis and examined the potential use of this strain to evaluate the safety of live attenuated vaccine candidates. Mice were inoculated intraperitoneally with a single dose of 1 × 10⁴, 1 × 10⁵, or 1 × 10⁶ CFU of B. abortus S19 or the vaccine candidate B. abortus S19ΔvjbR and monitored for the development of side effects, including osteoarticular disease, for 13 weeks. Decreased body temperature, weight loss, splenomegaly, and deformation of the tails were observed in mice inoculated with B. abortus S19 but not in those inoculated with S19ΔvjbR Histologically, all S19-inoculated mice had a severe dose-dependent inflammatory response in multiple organs. The inflammatory response at the tail was characterized by the recruitment of large numbers of neutrophils, macrophages, and osteoclasts with marked bone destruction. These lesions histologically resembled what is typically observed in Brucella-infected patients. In contrast, mice inoculated with B. abortus S19ΔvjbR did not show significant bone changes. Immunofluorescence, in situ hybridization, and confocal imaging demonstrated the presence of Brucella at the sites of inflammation, both intra- and extracellularly, and large numbers of bacteria were observed within mature osteoclasts. These results demonstrate the potential use of the NOD-scid IL2rγ^null mouse model to evaluate vaccine safety and further study osteoarticular brucellosis.