Relapsed Brucellosis Presenting as Neurobrucellosis with Cerebral Vasculitis in a Patient Previously Diagnosed with Brucellar Spondylitis: A Case Report

Meningoencephalomyelitis Caused by Brucella canis: A Case Report and Literature Review

Human brucellosis, one of the most common zoonoses worldwide, is rare in Japan. Brucella canis is the specific pathogen of human brucellosis carried by dogs. According to an epidemiological study of B. canis infection in Japan, B. canis is the specific pathogen of human brucellosis in dogs. We herein report a rare case of meningoencephalomyelitis caused by B. canis in a 68-year-old Japanese man. Neurobrucellosis was diagnosed based on a serum tube agglutination test and abnormal cerebrospinal fluid findings. The patient was started on targeted treatment with a combination of doxycycline and streptomycin. Although extremely rare, neurobrucellosis should be considered in patients with a fever of unknown origin and unexplained neurological symptoms.

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.

Evaluation of clinical, diagnostic features and therapeutic outcome of neurobrucellosis: a case series and review of literature

AIM

In this study, we aimed to discuss the clinical features, laboratory findings, treatment and outcome of seven cases of neurobrucellosis from a tertiary care center and review the available global literature.

MATERIALS AND METHODS

The diagnosis of neurobrucellosis was established using the following criteria in our setting: (1) signs and symptoms of neurological infection with examination of cerebrospinal fluid (CSF) revealing signs of meningitis, (2) isolation of Brucella spp. from blood and/or CSF and/or antibody titer ≥1:160 in serum using standard agglutination test (SAT) and/or the presence of anti-Brucella antibodies in CSF and/or detection of Brucella spp.-specific DNA from CSF using PCR. A literature search was performed to review previous cases of neurobrucellosis published worldwide during the last 30 years.

RESULTS

The proportion of neurobrucellosis was 2.8% in our setting. Fever with headache and altered sensorium were the major presenting complaints. Brucella melitensis was isolated from blood culture in 6 patients. From the literature search, a total of 221 cases of neurobrucellosis were reviewed and analyzed. Meningitis (32.6%), loss of hearing (25.8%) and encephalitis (14.9%) were the most common clinical features. Involvement of cranial nerves, polyradiculopathy and paraplegia were the major complications found in patients with neurobrucellosis.

CONCLUSIONS

Neurobrucellosis should always be considered in the differential diagnosis of befitting neurological, rheumatological, and neuropsychiatric presentations in endemic regions for brucellosis. To prevent morbidity and mortality associated with neurobrucellosis, a multimodal diagnostic approach is essential for early and accurate diagnosis and effective treatment.

Polymerase Chain Reaction-Based Assays for the Diagnosis of Active and Relapsed Cases of Human Brucellosis

This study aimed to compare polymerase chain reaction (PCR) with serum agglutination test (SAT) in the diagnosis of patients before and 6 months after treatment. Peripheral blood specimens from 50 patients with brucellosis (case group) and 30 subjects without brucellosis (control group) were selected and entered into the study. The diagnosis of brucellosis was established using SAT ≥ 1:160 and 2-mercaptoethanol (2-ME) ≥ 1:80 with clinical signs and symptoms compatible with brucellosis. For each case, both before treatment and 6 months after completion of therapy, SAT, 2-ME, and PCR were performed. Subjects in the control group were assessed by the same tests at the initial visit. In the case group, 50 patients (36 males, 14 females) with the mean age of 43.6 ± 14.5 years were evaluated. The mean age of the control group was 40.6 ± 14 years. Among the 50 patients whose nested PCR assays were initially positive, 43 (86%) were negative 6 months after completing treatment. Relapse occurred in five (10%) patients within 6 months after treatment and all were PCR positive. None of the patients in the control group was PCR positive. Results show that PCR seems to be highly sensitive and specific, and therefore is a useful method for both the initial diagnosis and detection of relapse or chronic brucellosis.