Noninfectious Pulmonary Complications in Hematologic Malignancy

Although infection accounts for the majority of acute diffuse airspace disease in dyspneic patients with hematologic malignancy, radiologists must also recognize a spectrum of noninfectious pulmonary conditions that can mimic infection. These less common entities are often unfamiliar and diagnostically challenging for radiologists but are also complex diagnoses for clinicians to establish without expert radiologic assistance. The misdiagnosis of infection and associated delays in correct diagnosis in these patients can significantly increase morbidity and mortality. The authors highlight noninfectious causes of dyspnea and associated diffuse parenchymal disease that often manifest with clinical characteristics mimicking infection. These include drug toxicities and treatment-related complications (particularly to new therapies and treatment regimens), associated edema and hemorrhage, complications of primary disease, and associated secondary disorders. Although imaging findings often overlap with those of infection, radiologists aware of these conditions can aid in accurate diagnosis by integrating knowledge of predisposing clinical scenarios, recognizing distinguishing imaging features and their temporal evolution, and correlating with clinical parameters. Although confirmation of these alternate noninfectious conditions is not always possible by imaging alone, radiologic interpretation may prompt additional specific tests that can corroborate the correct diagnosis. Timely accurate diagnoses of noninfectious causes can improve diagnostic accuracy and patient outcomes in this vulnerable population.