Pact with the devil: alemtuzumab therapy, immune suppression and infectious complications in chronic lymphocytic leukemia.

Infectious complications are an important cause of hospitalization in patients diagnosed with chronic lymphocytic leukemia. The pathogenesis of infection is complex, involving both disease-induced and treatment-related immune depression. During the last decade, the management of chronic lymphocytic leukemia (CLL) has been redefined by the approval of monoclonal antibody-based treatment, which resulted in improved therapeutic responses. Nonetheless, the profound lymphopenia induced by monoclonal agents was accompanied by increased incidence of infections caused by a new spectrum of opportunistic microorganisms. We report the case of a patient with hypercellular CLL who received Alemtuzumab as first line therapy and obtained a satisfactory therapeutic response, but developed subsequent atypical infectious complications.