Esteban Martinez

Neopterin and opportunistic infections in HIV-infected patients

Neopterin has been proven useful as a screening test for cytomegalovirus infection in blood donors [3]. It is widely accepted as a prognostic marker of human immunodeficiency virus (HIV) infection, and its increase is generally thought to correlate with the degree to which cellular immunity is activated in HIV infection [1, 2]. However, changes in serum concentrations of neopterin may be due not only to progression of HIV infection but also to the development of opportunistic infections, and for this reason its monitoring may provide early evidence of the appearance of acquired immunodeficiency syndrome. We are prospectively following 380 HIV-infected patients who have had serum neopterin, /~2-microglobulin and adenosine deaminase (ADA) concentrations measured at intervals of 3-6 months. The /~2-microglobulin level was measured by radioimmunoassay (/~2-micro RIA, Pharmacia Diagnostics, Uppsala, Sweden), neopterin by radioimmunoassay (Immutest neopterin, Henning Berlin, Berlin, FRG), and ADA by a kinetic ultraviolet method (Boehringer Mannheim, Mannheim, FRG). At baseline, staging of HIV infection in our patients were as follows (Centers for Disease Control): 198 (53.2%) in stage II, 55 (14.8%) in stage III, and 119 (32%) in stage IV. Serum neopterin and ADA levels significantly increased with progression of the disease (Table 1). Furthermore, a high correlation between serum levels of neopterin and those of/~2-microglobulin (r=0.658, P=0.0001) and CD4 cell count (r=0.364, P= 0.0001) was found in our patients. ADA levels showed a lower correlation with ,62-microglobulin (r=0.17, P=0.001) and neopterin (r=0.13, P=0.02) and no correlation with CD4 count (r=0.08, P=0.11). During a mean follow-up time of 8.3-+3.4 months, 20 patients (5.2%) developed opportunistic infections: pulmonary tuberculosis (4), Pneumocystis carinii pneumonia (4), generalized cytomegalovirus infection (3), disse-