Epstein-Barr virus viral load in human immunodeficiency virus-positive patients with reactive hemophagocytic syndrome

Because human immunodeficiency virus (HIV)-infected patients control Epstein-Barr virus (EBV) replication poorly, we hypothesized that reactive hemophagocytic syndrome (HS) in these patients may be associated with poor control of EBV. The files of 314 patients with a suspected diagnosis of HS were retrospectively reviewed. EBV viral load at the time of HS was compared between HIV-positive and -negative patients. A confirmed diagnosis of HS was made in 162 patients [109 males, median age 48 (35-62) years]. Among them, 61 (38%) were HIV positive [median HIV viral load 3.2 (1.6-5.5) log/ml, median CD4 count 94 (28-190)/mm(3)]. The median EBV viral load was significantly higher in HIV-positive than in HIV-negative patients [4.0 (2.9-4.6) vs 2.5 (0-4.2) log/ml, p = 0.002]. It was higher both in patients with hematological malignancy-associated HS [4.0 (2.9-4.4) vs 2.9 (0-4.9) log/ml, p = 0.03] and in patients with infection-associated HS [3.9 (0-4.9) vs 0 (0-4.1) log/ml, p = 0.14]. However, EBV viral load was not significantly higher in HIV-infected patients with confirmed HS than in HIV-infected patients for whom HS was unlikely [4.0 (2.9-4.6) vs 3.9 (2.6-4.1) log/ml, p = 0.48].The high EBV viral load observed in HIV-infected patients with HS may be more likely to reflect the chronic HIV infection than to be the direct trigger of HS.