Chronic alcoholic liver disease is associated with several immunological alterations: depressed T-cell function, low serum gamma-interferon, and high serum tumour necrosis factor (TNF-alpha) and interleukin levels. Therefore, macrophage activity seems to be enhanced. Some cytokines, such as TNF-alpha, exert adverse effects on chronic alcoholic liver disease, so that protracted activation of macrophages with continuous TNF-alpha production may aggravate alcoholic hepatitis. Based on these facts we have sequentially determined serum levels of TNF-alpha, 1 beta interleukin (IL-1 beta), gamma-interferon and neopterin--a macrophage product--at admission, and at the end of the first, third and sixth weeks after admission, of 43 patients affected by alcoholic hepatitis, and of 20 age-matched sanitary workers as controls. Our patients showed higher levels of neopterin and lower levels of IL-1 beta and gamma-interferon than the controls; TNF-alpha levels in our patients were almost significantly higher than in controls. TNF-alpha levels at admission were higher in the patients who died (P = 0.025). TNF-alpha and neopterin levels showed no trend to normalization in patients who died, with higher levels of neopterin at first and third weeks and higher TNF-alpha and gamma-interferon levels at first week. Using logistic regression analysis, serum TNF-alpha levels at admission showed significant (P = 0.045), independent effects on mortality, as well as serum neopterin (P = 0.0026) at the first week. Thus, enhanced macrophage activity, measured by serum levels of TNF-alpha and neopterin seems to be related to a worse prognosis in alcoholic hepatitis.