What is the most common complication observed in patients with chronic lymphocytic leukemia (CLL)?

In chronic lymphocytic leukemia (CLL), the most common complication is infection. This is primarily due to the immune system's compromised function resulting from the disease and treatment. CLL is characterized by the proliferation of abnormal lymphocytes that do not function properly, leading to a reduced ability to mount effective immune responses. Patients often experience neutropenia, hypogammaglobulinemia, and other immune defects, which contribute to an increased susceptibility to infections.

Furthermore, infections in CLL patients can be caused by both encapsulated bacteria and viral pathogens. The chronic nature of the disease and the treatments, such as chemotherapy or immunotherapy, can further weaken the immune defense, making infections a significant concern that must be monitored and managed closely in these patients. This highlights the importance of preventive measures, vaccinations, and, when necessary, prophylactic antibiotics to help reduce the risk of infections in those with CLL.