Brucellosis: Morphofunctional Correlation and Immune Response in Brucella Infection

Abstract

Few infectious diseases combine high global prevalence with such low clinical recognition as brucellosis, a neglected bacterial zoonosis with an estimated 2.1 million new cases annually. The causative agent, Brucella, is a facultative intracellular Gram-negative coccobacillus that survives within macrophages by blocking phagolysosomal fusion via its type IV secretion system, establishing a replicative niche in the endoplasmic reticulum. This systematic review (PRISMA protocol) analyzes 11 studies on the morphofunctional correlation and immune response in the infection. The results show that T2-weighted magnetic resonance imaging differentiates brucellar spondylitis from tuberculous spondylitis, with significantly higher values ​​(p<0.001). The SSC classification allows for severity stratification and treatment guidance, with improvement in ESR and CRP at six months. Subsequent surgical intervention better corrects kyphosis with a shorter surgical time. Relapse (12.2%) is associated with advanced age, female sex, and agricultural occupation, not with focal complications. Hematological findings include anemia (25.9%), monocytosis (15.9%), and eosinopenia (10.3%). Children present with more bacteremia and peripheral arthritis; adults, with greater vertebral involvement. Genomic analysis reveals an open pan-genome with 21,800 gene families and resistance and virulence genes, indicating genetic plasticity of the genus. The integration of morphofunctional and immunological findings allows for a clinically useful pathophysiological approach.