Invasive fungal infections in pediatric patients treated with tumor necrosis alpha (TNF-) inhibitors

Macromolecular immunosuppressive monoclonal antibodies and fusion proteins directed against molecules or cells involved in inflammation and immunity represent a recent and important addition to our therapeutic armamentarium. Tumor necrosis alpha (TNF) is a cytokine involved in systemic inflammation and clinical utilization of its antagonists has revolutionized treatment of juvenile rheumatoid and psoriatic arthritis, ankylosing spondylitis, Crohn's disease, ulcerative colitis, and plaque psoriasis. Clinical utility has also been demonstrated for use against steroid-refractory graft-vs-host disease and other immune-mediated conditions. Currently, five anti-TNF agents are approved by the European Medicines Agency (EMA), including the monoclonal anti-TNF antibodies infliximab, adalimumab, golimumab and certolizumab pegol along with etanercept, a TNF-receptor/IgG-Fc fusion protein. Theoretical considerations related to their mode of action and clinical observations suggest that opportunistic infectious complications should be seriously considered as possible adverse events of macromolecular immunosuppressants. The purpose of this review is to critically analyze the literature on invasive fungal infections (IFIs) occurring in association with TNF inhibitors alone or in combination with other immunosuppressive agents, with a focus on pediatric patients, and to provide a framework of evaluating the risk for IFIs in this population.