Pomalidomide-Induced Lung Injury Mimicking COVID19 Pneumonia

Multiple chemotherapy medications are known to cause acute lung injury. One medication that causes injury to the lungs and can present with hypoxia is pomalidomide, a medication used for multiple myeloma. Chemotherapy-induced lung injury is commonly mistaken for infectious pneumonia. The diagnosis becomes difficult since patients are immunosuppressed and prone to infection. The presentation is complicated further during pandemics. Coronavirus Disease 19 (COVID19) has become a very common diagnosis during the pandemic in 2020. Multiple diagnostic tests are required to rule out infectious processes including that of less common organism. To ultimately deem the injury to be caused by medication side-effect is a diagnosis of exclusion. The following case illustrates the complexity of the diagnosis. Multiple case reports show a potential association between pomalidomide and acute lung injury. Lung injury arises about 120 to 480 days after continuous use. Pomalidomide promotes T-cell proliferation and secretion of IL-2 and INF-y. IL-2 causes increased vascular permeability leading to pulmonary edema and acute lung injury. INF-y further promotes hyperoxia-induced lung injury. Treatment is with pomalidomide cessation and corticosteroids. In some cases, the medication can be reintroduced but there have been reports of recurrence.