Immunomodulatory
antibodies that enhance the immune system to fight
cancer are revolutionizing the treatment of patients with an expanding variety of
malignancies. There is a unique spectrum of side effects associated with immunomodulatory
antibodies, termed immune-related adverse events (irAEs), which include
colitis and
hepatitis among others. The treatment of refractory or severe irAEs can occasionally require significant immunosuppression, involving
steroids or
tumor necrosis factor-alpha antagonists, placing these patients at risk for
infections. We present the first reported case to our knowledge of an
opportunistic infection in a patient treated with an immunomodulatory antibody. As the use of immunomodulatory
antibodies expands and more patients develop irAEs that require treatment with immunosuppression, recognition of the potential for
opportunistic infections in this emerging patient population will be critical. Prospective trials are needed to define the optimal immunosuppressive management of irAEs and determine whether prophylactic
antiviral, antibacterial, or antifungal
therapies are beneficial in this unique population.