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A1961 - Mycobacterium Massilliense Lung Disease Successfully Treated by Oral Antibiotic Therapy Following 2 Weeks Intravenous Treatment
Author Block: M. Matsumoto1, M. Suzuki2, Y. Yu1, N. Takei2, H. Kimura2, K. Nagaoka1, S. Konno3, M. Nishimura4; 1Department of Respiratory Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan, 2First Department of Medicine, Hokkaido University School of Medicine, Sapporo, Japan, 3Hokkaido Univ, School of Med, Sapporo, Japan, 4Depatment of Respiratory Medicine, Hokkaido Univ Faculty of Medicine and Graduate School of Medicine, Sapporo, Japan.
Introduction: Mycobacterium massilliense (M. massilliense) has been recognized as separate species from Mycobacterium abscessus (M. abscessus) recently. Although M. abscessus has difficulty in treating strategy due to its resistant in many antibiotics and side effects from long term antibiotic therapy, M. massilliense, has high sensitivity to antibiotics and has better outcome. Some studies have shown that long term antibiotic therapy like regimens used in M. abscessus are not necessary, but the optimal regimen to treat M. massilliense is not yet known. Case: A 49-year-old woman with systemic lupus erythematosus, anti-phospholipid anti-body syndrome, lymphocytic interstitial pneumonia as well as treatment history of Mycobacterium avium admitted to our hospital because of cough and sputum for 2 months. Her sputum examination revealed M. abscessus for 2 times while outpatient visits, therefore she was hospitalized to treat M. abscessus. On admission, her CRP value was 1.09 mg/dL, CT scan showed granular shadow in the entire lung and showed bronchiectasis and consolidation in her right middle lobe. Administration of clarithromycin, at 800 mg/day, imipenem / cilastatin, at 1.5 g/day, and 200mg/day of amikacin was started. Concurrently, we analyzed the sputum specimen for 16s-rRNA, and M. massilliense was identified as sub- species of M. abscessus. After continuing the treatment for 2 weeks, cough and sputum disappeared, CRP had become negative, granular shadow and consolidation in the right middle lobe improved. Because of her rapid recovery, we shifted to oral antibiotics including 800 mg/day of clarithromycin and 100 mg/day of sitafloxacin. After 6 months of the treatment, her condition was still improving without any side effect. Discussion: The treatment response rates to antibiotics are much higher in patients with M. massilliense lung disease than in with M. abscessus lung disease. This is mainly due to the presence of erm gene, which induces macrolide resistant in M. abscessus. In addition, the fact that the prevalence of M. massilliense is increasing indicates the necessity of new regimen. We are collecting more cases to confirm this regimen is useful. Conclusion: We report a successful treatment course of M. massilliense lung disease, by oral antibiotic therapy following only 2 weeks of intravenous antibiotic treatment.