Risks and burden of viral respiratory tract infections in patients with multiple myeloma in the era of immunomodulatory drugs and bortezomib: experience at an Australian Cancer Hospital

INTRODUCTION: Infections are a leading cause of morbidity and mortality in patients with multiple myeloma. The epidemiology, risk factors and outcomes of viral respiratory tract infections (vRTI) are not well described in patients with multiple myeloma managed with novel agents, the current standard of care. METHODS: Patients with myeloma from 2009 to 2012 who tested positive on respiratory virus multiplex polymerase chain reaction had clinical, radiological and microbiological records reviewed. The Fourth European Conference on Infections in Leukaemia (ECIL-4) definitions of RTI were applied. Univariate and multivariate regression analysis of risk factors was performed using vRTI as the evaluable outcome. RESULTS: Of 330 patients, 75 (22.7 %) tested positive for a total of 100 vRTI episodes. All patients received thalidomide, lenalidomide or bortezomib in combination with myeloma therapies (median of three treatment regimens). vRTI occurred most commonly in patients with progressive disease, and receipt of more than three lines of myeloma therapy was associated with an increased risk of vRTI (p < 0.01). Amongst key respiratory pathogens, influenza was associated with the highest hospital admission rate (66.7 %), ICU admission rate (41.6 %) and mortality (33.3 %) whilst RSV was associated with prolonged hospital stay. CONCLUSION: Patients with multiple myeloma and advanced disease managed with multiple lines of therapy are at risk for vRTI, and targeted interventions for prevention/treatment are required.