Interleukin-8 is elevated in severe hand, foot, and mouth disease

Enterovirus 71 (EV71) infections can cause hand, foot, and mouth disease (HFMD), which is a potentially fatal illness in children. Epidemics of HFMD are seen every year globally and present an increasing threat to public health worldwide.

To identify potential severity markers for severe HFMD, laboratory findings and levels of eight serum cytokines in 143 EV71-infected patients in Beijing You'an Hospital were analyzed. Patients were grouped by disease severity: Mild (no severe complications) (n = 59), isolated isolated brainstem encephalitis (BE) (n = 47), isolated pulmonary edema (PE) (n = 12), and BE+PE (n = 25).

IL-8 levels peaked at day one after admission and were found to be correlated to disease severity, maximal body temperature, and length of hospital stay. Among all tested cytokines, IL-8 was correlated to only IL-6 (p = 0.010). IL-6 and IL-10 were elevated in most patients (98.6% and 70.6%), but not correlated to disease severity (both p > 0.05). IFNγ was only negatively correlated to mild cases (p = 0.025).

IL-8 was correlated to disease severity of HFMD. IL-6 and IL-10, although elevated in most HFMD patients, were not correlated to disease severity.