Methods: cross-sectional study, carried out in serological samples of patients with laboratory-confirmed diagnosed for acute cases (AC), chronic cases (CC) and fatal CHIKV cases (FC). The samples were supplied by the virology laboratory of the National Health Institute and through commercial kit 13 cytokines were processed
Results: 164 samples were analyzed, 50 from patients with AD, 25 from FC due to CHIKV and 89 from patients with CC. The average age was 48.2 years ± 24.4 SD. AC were more prevalent in the extreme ages of life (<10 years and>70 years), and the CC in young adults and intermediate adults (20-60 years) (p <0.05). The median time taken for the sample was 4.5 [IQR3] days for acute cases and 7 days [IQR1.75] for FC. Ten plasma cytokines (INF-gamma, IL-10, IL-13, IL-17a, IL-2, IL-4, IL-5, IL-6, TGF-α, TNF-α) were significantly elevated in patients deceased compared to patients with acute infection (p <0.005). In patients with FC, IL-6 was the proinflammatory cytokines with the highest median value and among the anti-inflammatory cytokines, IL-10. Exception of GM-CSF and IL-12, the comparison of medians between FC and patients with CC (INF-gamma, IL-10, IL-13, IL-17a, IL-2, IL-4, IL- 5, IL-6, LT-α / TNF-β, TGF-α, TNF-α) presented statistically significant differences (p <0.05). The levels of IL-6 and IFN-γ were 8 and 2 times higher in patients with AC than in the group with CC.
Conclusion: This is the first study conducted in Colombia, which provides evidence on cytokine levels in the acute, fatal and chronic outcome of patients with CHIKV. AC had an increase in IFN-γ, IL-5, IL-6, IL-10, IL-12, IL-17a and TNF-α cytokines, which if persisted elevated for more than 3 months with some decreased levels of IFN-γ and IL-6, maybe progression to chronic phase. If in addition of acute phase cytokines, IL-2, IL-4, IL-13, LT-α/TNF-β, TGF-α increase, the disease maybe severe or fatal. Cytokines, especially IL-6, is becoming a tool for monitoring, evolution and prognosis of CHIKV disease.
National Health Institute, Universidad del Norte: