Why was Leonhard Euler blind?

This review of Brucella-host interactions and immunobiology discusses recent discoveries as the basis for pathogenesis-informed rationales to prevent or treat brucellosis. Brucella spp., as animal pathogens, cause human brucellosis, a zoonosis that results in worldwide economic losses, human morbidity, and poverty. Although Brucella spp. infect humans as an incidental host, 500,000 new human infections occur annually, and no patient-friendly treatments or approved human vaccines are reported. Brucellae display strong tissue tropism for lymphoreticular and reproductive systems with an intracellular lifestyle that limits exposure to innate and adaptive immune responses, sequesters the organism from the effects of antibiotics, and drives clinical disease manifestations and pathology. Stealthy brucellae exploit strategies to establish infection, including i) evasion of intracellular destruction by restricting fusion of type IV secretion system-dependent Brucella-containing vacuoles with lysosomal compartments, ii) inhibition of apoptosis of infected mononuclear cells, and iii) prevention of dendritic cell maturation, antigen presentation, and activation of naive T cells, pathogenesis lessons that may be informative for other intracellular pathogens. Data sets of next-generation sequences of Brucella and host time-series global expression fused with proteomics and metabolomics data from in vitro and in vivo experiments now inform interactive cellular pathways and gene regulatory networks enabling full-scale systems biology analysis. The newly identified effector proteins of Brucella may represent targets for improved, safer brucellosis vaccines and therapeutics. Show more

We describe the neurological involvement in brucellosis and revisited diagnostic criteria for neurobrucellosis. Patients with laboratory-confirmed brucellosis who were consequently hospitalized were observed prospectively in a brucellosis-endemic region. The neurobrucellosis was diagnosed by any one of the following criteria: (1) symptoms and signs consistent with neurobrucellosis; (2) isolation of Brucella species from cerebrospinal fluid (CSF) and/or presence of anti-Brucella antibodies in CSF; (3) the presence of lymphocytosis, increased protein, and decreased glucose levels in CSF; or (4) diagnostic findings in cranial magnetic resonance imaging or CT. Lumbar puncture was performed in 128 laboratory-confirmed brucellosis cases who had neurological symptoms and signs, and 48 (37.5%) were diagnosed as neurobrucellosis. The sensitivity of tube agglutination (TA) in CSF was 0.94, specificity 0.96, positive predictive value 0.94, and negative predictive value 0.96. Brucella bacteria were isolated from CSF in 7 of 48 patients (15%). The mean age of 48 neurobrucellosis patients was 42 years (SD, 19 years), and 16 (33%) were female. The most common neurological findings were agitation (25%), behavioral disorders (25%), muscle weakness (23%), disorientation (21%), and neck rigidity (17%). Cranial nerves were involved in 9 of 48 patients (19%). One patient was left with a sequela of peripheral facial paralysis and 2 patients with sensorineural hearing loss. Patients with severe and persistent headache and other neurologic symptoms and signs should be considered for neurobrucellosis in endemic regions and to possibly receive longer therapy than 6 weeks. Brucella TA with Coombs test in CSF is sensitive and specific by using a cutoff of ≥1:8. Show more