Pulmonary MRI - a new approach for the evaluation of febrile neutropenic patients with malignancies

Goals of work Immunocompromised patients with malignant diseases often suffer from pulmonary infections. Early detection of these life-threatening infections is crucial to start effective treatment. The gold standard for the diagnosis of these disorders is high-resolution computed tomography (HR-CT) of the chest. This method, however, has limitations, for instance, in the discrimination of early interstitial infiltrates and the use of X-rays. We conducted a study to determine the feasibility and sensitivity of magnetic resonance imaging (MRI) of the lung compared to HR-CT in immunocompromised patients with persistent fever in neutropenia and suspected pneumonia. Materials and methods Between January 2003 and July 2004, 50 consecutive neutropenic patients with fever of unknown origin and negative chest X-ray were examined with HR-CT of the lungs. Patients with pulmonary infiltrates were further examined with MRI of the chest within 24 h after HR-CT using a specific lung protocol. In addition, microbiological testing was performed for the characterization of the causative pathogen. Results Of 50 patients, 35 had pulmonary infiltration according to HR-CT; these were examined with MRI of the lungs. MRI showed a high correlation (91%) with the findings in HR-CT. Both HR-CT and MRI were feasible in 94% of the examined patients. In 12 of 35 patients, fungal pathogens were identified in microbiological testing. Conclusions MRI of the lungs is feasible in neutropenic patients with suspected pulmonary infection. Compared to HR-CT, MRI displays a high sensitivity in the detection of pulmonary infiltrates. MRI offers the opportunity of follow-up examinations without repeated X-ray exposure to the patient.