[FDG-PET-CT and the diagnosis of malignancy of pulmonary nodules and mass lesions]. / TEP-TDM-FDG et diagnostic de malignité des nodules et masses pulmonaires.

BACKGROUND: Positron emission tomography with 2-[18]-fluoro-2-deoxy-D-glucose coupled to a dedicated CT scanner (FDG-PET-CT) is an accurate test for the diagnosis of malignancy of pulmonary nodules. We have assessed the diagnostic accuracy of this test at the Lyon Sud Hospital Centre (LSHC). METHODS: We examined retrospectively 93 patients with no past history of cancer who had had a FDG-PET-CT evaluation for the diagnosis of pulmonary nodules or mass lesions between the 1st January 2005 and the 30th June 2006 at the CHLS. The results of the PET scans were compared with the histological findings or follow-up imaging. RESULTS: The sensitivity was 97.85 (IC 95% Sc =[93.4; 100]), the specificity was 79.2% (IC95% Sc=[67.6; 90.7]), the positive predictive value was 81.5%, the negative predictive value was 97.4% and the accuracy was 88.2%. CONCLUSIONS: In current practice these results support the validity of FDG-PET-CT at the LSHC for the diagnosis of malignancy of pulmonary nodules and mass lesions while giving nuclear medicine physicians the opportunity to improve their standards of practice.

[Nocardial pulmonary infection]. / Infections pulmonaires à Nocardia.

INTRODUCTION: Nocardial pneumonias are due to a genus of aerobic, filamentous, partly acid-alcohol fast, mainly Gram positive, actinomycetes. CASE REPORT: We report here two cases of nocardial pneumonia. The first was a 62 year old man with a history of fludaribine treatment and bone marrow transplant for lymphocytic leukaemia. During the investigation of pyrexia evidence of N. farcinica infection was found in the bronchial secretions. The second case was a man of 61 receiving long term corticosteroids and cytotoxic chemotherapy. Investigation of a pneumonia with pleural effusion found evidence, on culture of blood and pleural fluid, of disseminated infection with N. nova (cerebral, pleural, pulmonary and splenic). CONCLUSION: Nocardiosis is a rare cause of pneumonia mainly occurring in immuno-compromised adults (corticosteroid therapy, HIV infection, transplantation, cancer or leukaemia). It should be suspected in the presence of pleuro-pulmonary symptoms associated with neurological and cutaneous signs, general deterioration and weight loss. The microbiology laboratory should be advised of this eventuality as soon as possible in order to optimise the search for the organism.