THE EFFECT OF UNDERLYING DISORDERS IN PATIENTS WITH MYCOBACTERIUM ABSCESSUS DISEASE

Abstract

ABSTRACT Mycobacterium abscessus belongs to the group of rapid-growing non-tuberculous mycobacteria (RGM) and is the infectious agent in over 80% of RGM chronic respiratory disease isolates. We evaluate the effect of underlying disorders in patients with Mycobacterium abscessus disease. We retrospectively reviewed medical records of all patients who visited or were admitted to the Kaohsiung Chung-wo Memorial hospital from January 2006 to May 2009 with positive Mycobacterium abscessus cultures. Identification of Mycobacterium abcessus disease was based on PCR restriction fragment length polymorphism and diagnosis was based on American Thoracic Society (ATS) criteria for diagnosis of disease due to NTM of 2007. During this period, 253 patients had a positive culture of Mycobacterium abscessus and only 50 patients met the ATS criteria for diagnosis. The patients were mostly elderly females, non smokers with underlying disorders. Majority (62%) of the patients had pre-existing lung disease; usually previous history of mycobacterial disease .Previous history of Tuberculosis (28%) was the most common underlying disorder and non of our patients had Cystic fibrosis. Patients with underlying disorders were significantly older (mean age 66.2yr) with more symptoms. Patients with pre-existing lung disease also had a longer duration of symptoms and were more likely to have a positive primary sputum sample. Underweight (BMI <18) was significantly associated with previous history of mycobacterial disease (p=0.006) and upper lung field cavities (p=0.020). The most frequent pattern on chest radiographs was consolidation (40%) mostly on the right lung (86%) and usually unilateral (68%). Extrapulmonary Mycobacterium abscessus disease was mostly disseminated and usually followed immunosuppressive drug treatment and post cosmetic surgery. Patients with previous history of Tuberculosis (p=0.021) were more likely to have failure of sputum conversion. Patients with Mycobacterium abscessus pulmonary disease were mainly elderly females, non smokers with underlying disorders. Patients with previous history of Tuberculosis were more likely to have failure of sputum conversion. In Taiwan, pre-existing lung disease, especially previous history of Tuberculosis seems to have a significant role in Mycobacterium abscessus pulmonary disease compared to western countries.