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.