Infectious complications in chronic lymphoid malignancy.

Taking steps to minimize, prevent, and treat infection in patients with chronic lymphoid malignancies, especially chronic lymphocytic leukemia, has always been a challenge. As more patients with these diseases live longer and lead productive lives upon successful initial treatment, strategies for preventing infections have become more important. Distinguishing patients at low risk for infection from those at high risk is a crucial but challenging issue. Unfortunately, there are hardly any data on the use of prophylactic antibiotics for patients with chronic lymphoid malignancy (CLL). If patients cannot be enrolled in a clinical trial, antibiotics with co-trimoxazole should be administered when steroids are warranted. They should also be administered in patients who have had a documented infection early in the treatment course and during neutropenia. Viral infections remain another controversial issue in patients with CLL receiving treatment, especially a purine analogue. Very low CD4 counts (less than 50 cells/mL) might predict for reactivation for herpes zoster. Outside of depleted CD4 counts, there are no other means of identifying a high-risk group. Based on limited data, it would be reasonable to administer herpes zoster prophylaxis to patients with CD4 counts that are severely depleted or to patients with a prior episode of zoster. Controversial issues still remain regarding immunoglobulin treatment, specifically cost, scarcity of the product, and adequate dose, which has not yet been established. We would consider intravenous immunoglobulin (Ig) replacement in patients with marked hypogammaglobulinemia (IgG less than 400 mg/dL) with more than two recent severe infections [1]. Lower Ig doses (240 mg/kg) have been shown to be equivalent to higher ones in this trial [1].