Reduction in Nontuberculous Mycobacteria at a Tuberculosis Hospital Following a Quality Assurance Intervention

Abstract

BackgroundNon tuberculous mycobacteria (NTM) are widely distributed in soil and water. NTM/Mycobacterium tuberculosis complex (MTBC) mixes may yield positive AFB smears falsely attributed to tuberculosis (TB) and false-resistance profiles for TB due to contaminated diagnostic samples. This as well as isolation of NTM may pose diagnostic and management problems. Texas Center for Infectious Disease (TCID) is a hospital for patients with confirmed TB. After a cluster of isolates of Mycobacterium gordonae was identified, a quality assurance review found inadequate protocols which included eating and drinking prior to collection. Changes made to the sputum collection protocol included reeducation of respiratory therapists and a sterile saline rinse intervention prior to sputum collection.MethodsAll sputa collected for AFB culture from diagnosed TB patients at TCID from January 1st, 2014 to December 31st, 2014 prior to the intervention and from August 1st, 2016 to January 31st, 2017, the 6 months following the quality assurance intervention were included. Sputum samples were processed at the Texas Department of State and Health Services (DSHS) Laboratory.ResultsA total of 1,853 sputum samples were processed; 1,288 from 2014 and 565 following the intervention. NTM decreased from 56 (4.3%) to 7 (1.2%) after the quality assurance intervention was instituted for a NTM decrease of 75.0%. M. gordonae decreased by 78.6%. No patients had evidence of NTM disease.ConclusionA breach in sputum collection protocols at TCID accounted for the increase in NTM isolation in 2014, half of which were M. gordonae. The reeducation of respiratory therapy staff and initiation of sterile saline rinse prior to sputum collection resulted in a significant reduction in the overall NTM rate. M. gordonae was isolated only three times following the intervention. At TCID, a location where tap water and bottled water contains NTM, drinking these prior to sputum collection possibly contributed to the cluster for NTM, especially M. gordonae. We recommend rinsing the mouth with sterile saline or water prior to sputum collection to decrease isolation of rarely pathogenic NTM.Disclosures All authors: No reported disclosures.