Multidrug-Resistant Pseudomonas aeruginosa Triggers Differential Inflammatory Response in Patients With Endophthalmitis.

Purpose: Infections with multidrug-resistant Pseudomonas aeruginosa (MDR-PA) lead to poor clinical outcomes in endophthalmitis patients, and its interactions with the host immune system remain largely unknown. The current study aimed to determine the association of MDR-PA infection with the cytokine expression profile in patients with endophthalmitis. Methods: Vitreous of 12 patients with culture-proven MDR-PA along with 12 samples from antibiotic-susceptible P. aeruginosa (S-PA) and 20 non-infectious controls were included in the study. Expression patterns of IL-6, IL-10, IL-1α, IL-1β, IFN-γ, TNF-α, IL-8, and GM-CSF in the vitreous were analyzed by multiplex immunoassay and correlated with the clinical severity. We also assessed the phosphorylation level of different immune pathway molecules. Results: In the MDR-PA group, significantly (P < 0.05) increased expression of IL-6, IL-8, IL-10, IL-1β, and TNF-α was observed in comparison with the S-PA group. The increased inflammatory mediators in MDR-PA correlated with the disease severity. Additionally, the increased expression of inflammatory mediators was positively correlated to the activation levels of Akt, STAT3, JNK, p70 S6 kinase, and NF-кB (P < 0.05) in the MDR-PA group. Conclusions: The current study shows the differential host immune response and phosphorylation levels of signaling molecules in MDR-PA endophthalmitis, thereby linking antibiotic resistance with distinct immune regulation. Translational Relevance: This study provides evidence for the use of inflammatory mediator levels of IL-6, IL-8, IL-10, IL-1β, and TNF-α as potential diagnostic biomarkers of MDR endophthalmitis warranting prompt administration of immune modulators to avoid irreversible damage to the retina and vision loss.