title: Serial CT findings of Mycobacterium massiliense pulmonary disease compared with Mycobacterium abscessus disease after treatment with antibiotic therapy.
abstract: OBJECTIVE
  To present the serial computed tomographic (CT) findings of lung abnormalities in Mycobacterium massiliense pulmonary disease compared with those in Mycobacterium abscessus disease.
  
  
  METHODS
  The institutional review board approved this retrospective study and waived informed consent. Serial chest CT scans of M massiliense (n = 34) and M abscessus (n = 24) pulmonary diseases were retrospectively reviewed. Patients were treated with clarithromycin-containing combination antibiotics regimen, and sputum examinations were performed regularly. CT scans were obtained at the beginning of antibiotic therapy, at the end of 4-week hospitalization, and at the time of 12-month antibiotic therapy.
  
  
  RESULTS
  All patients with M massiliense disease had sputum conversion during treatment, whereas 50% of patients with M abscessus disease had sputum conversion. The most common CT findings of M massiliense disease at presentation were cellular bronchiolitis (n = 34, 100%), bronchiectasis (n = 34, 100%), consolidation (n = 33, 97%), nodules (n = 32, 94%), and cavities (n = 15, 44%). These findings were similar in M abscessus disease. Thirty (88%) patients with M massiliense disease had decrease in overall CT score at 12-month therapy, whereas only eight (33%) patients with M abscessus disease had a decrease (P < .0001). Improvement was noticeable in cellular bronchiolitis and cavity in M massiliense disease.
  
  
  CONCLUSIONS
  Common CT findings of M massiliense diseases overlap with those of M abscessus disease. However, responses to antibiotic treatment are much different; in M massiliense disease, negative sputum conversion is accomplished in all patients and serial CT scans show improvement in most patients.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
authors.forename: Hyun Su
authors.initials: HS
authors.lastname: Kim
authors.forename: Kyung Soo
authors.initials: KS
authors.lastname: Lee
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Koh
authors.forename: Kyeongman
authors.initials: K
authors.lastname: Jeon
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Lee
authors.forename: Hee
authors.initials: H
authors.lastname: Kang
authors.forename: Joonghyun
authors.initials: J
authors.lastname: Ahn
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000890:Anti-Infective Agents; D002939:Ciprofloxacin / Q000627:therapeutic use; D017291:Clarithromycin / Q000627:therapeutic use; D003937:Diagnosis, Differential; D004318:Doxycycline / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000000981:diagnostic imaging* / Q000188:drug therapy* / Q000382:microbiology; D009170:Nontuberculous Mycobacteria / Q000187:drug effects*; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D013183:Sputum / Q000382:microbiology; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D002939:Ciprofloxacin; D017291:Clarithromycin; D004318:Doxycycline