Serum Cytokine Profiles and Inflammatory Markers in Brucellosis-Associated Arthritis

Brucellosis is a common zoonotic infection in India, caused by a facultative intracellular, Gram-negative coccobacillus and frequently presents with nonspecific symptoms. This study aimed to assess serum cytokine levels (IL-6, IL-10, IFN-γ, and IL-2) by ELISA and to correlate them with inflammatory markers (ESR, and CRP)in patients with suspected brucellosis presenting with rheumatoid arthritis–like manifestations and polyarthralgia. This study included 111 patients, comprising 72 brucellosis-positive arthritis patients and 39 brucellosis- negative arthritis patients as controls. In this study, we investigated the variation in levels of four cytokines (IL-2, IL-6, IL-10 and IFN-γ) among brucellosis-positive and brucellosis-negative arthritis patients and their relationship with clinical parameters. The mean serum levels of IL-2 and IL-10 were markedly higher in brucellosis-positive arthritis patients. As brucellosis is an important cause of inflammatory arthritis, characterized by elevated serum levels of IL-10 and IL-2 and increased inflammatory markers, including ESR and CRP, along with relatively lower levels of IFN-γ and IL-6, which are linked to the inflammatory rheumatoid arthritis. The observed associations with raw dairy consumption, contact with unvaccinated livestock, and direct animal exposure highlight the need for early diagnosis, effective livestock immunization programs, and strengthened One Health–based public health interventions to reduce disease burden