Severe dengue pathogenesis is not fully understood, but high levels of proinflammatory
cytokines have been associated with
dengue disease severity. In this study, the
cytokine levels in 171 sera from Mexican patients with primary
dengue fever (DF) and
dengue haemorrhagic
fever (DHF) from dengue virus (DENV) 1 (n = 116) or 2 (n = 55) were compared. DF and DHF were defined according to the patient's clinical condition, the primary
infections as indicated by
IgG enzymatic immunoassay negative results, and the infecting serotype as assessed by real-time reverse transcription-polymerase chain reaction. Samples were analysed for circulating levels of
interleukin (IL)-12p70,
interferon (IFN)-γ, tumour
necrosis factor (TNF)-α,
IL-6, and
IL-8 using a commercial cytometric bead array. Significantly higher IFN-γ levels were found in patients with DHF than those with DF. However, significantly higher IL-12p70, TNF-α, and
IL-6 levels were associated with DHF only in patients who were infected with DENV2 but not with DENV1. Moreover, patients with DF who were infected with DENV1 showed higher levels of IL-12p70, TNF-α, and
IL-6 than patients with DHF early after-
fever onset. The
IL-8 levels were similar in all cases regardless of the clinical condition or
infection serotype. These results suggest that the association between high proinflammatory
cytokine levels and
dengue disease severity does not always stand, and it once again highlights the complex nature of DHF pathogenesis.