PURPOSE: To describe a case-series of Acid-Fast Bacilli (AFB) positive smears in terms of prevalence, demographics, and co-morbidities.
METHODS: A retrospective chart review of all AFB positive smears in 150-bed hospital over a 5-year period. The samples were divided into mycobacteria tuberculosis (MTB) and Non-Tuberculous Mycobacterium (NTM). These were subdivided into Fast growers (Group 1) and Slow-growers (Group 2). NTM were stratified according to co-morbidities looking for significant correlations: Chronic Obstructive Pulmonary Disease (COPD), Gastro-esophageal reflux disease (GERD) Asthma, Diabetes, Connective Tissue Disorders, Previous tuberculosis, and HIV/AIDS. A Fisher’s exact test was used to determine significance amongst the stratified groups.
RESULTS: We identified 101 cases, 3 were MTB and 98 were NTM. Group 1 had 32 Fast Growers, with M. fortuitum being the most prevalent (46.9 %). Group 2 had 66 Slow Growers with M. avium complex being the most prevalent (92.8 %.) 59.2 % were female and 40.8 % were male. COPD was the most prevalent co-morbidity (28.6 %,) followed by GERD ( 22.8 %). Asthma, Diabetes Mellitus, and Bronchiectasis occurred in 9.2 % of the population individually. When stratified according to co-morbidities, Group 1 and Group 2 had no statistically significant correlation with COPD, GERD, Asthma, Diabetes Mellitus, CTD, Bronchiectasis, HIV/AIDS and previous TB exposure. There was also no statistically significant correlation with male in group1 or group2. However females were 2.5 times more likely to have a slow grower than a fast growers (p=.03).
CONCLUSION: There was a much higher prevalence of NTM than M Tuberculosis in our hospital. We did not find any statistically significant correlation between fast and slow growers when stratified amongst co-morbidities. Previous studies had sited a statistical significant relationship with GERD; however our study failed to show this correlation. Slow growers, specifically mycobacterium avium complex, were more prevalent, which correlates with previous studies.
CLINICAL IMPLICATIONS: In our study there were no significant populations for either slow-growing or fast-growing mycobacterium species.
DISCLOSURE: Michael Alvarez, No Financial Disclosure Information; No Product/Research Disclosure Information