Atypical Mycobacterium Detection in Refractory Chronic Rhinosinusitis

Abstract

Objective: Atypical mycobacterium (AM) involvement in refractory chronic rhinosinusitis (CRS) is sought by some surgeons with customary acid-fast bacilli cultures (AFBC) in the operating room (OR). We evaluate our experience with AM in CRS by describing: 1) associated risk factors, 2) species identified, and 3) frequency of positive cultures in clinic vs OR. Method: AFBC taken between 2005 and 2010 were identified from microbiology laboratory databases. Charts were reviewed for gender, age, medical history, risk factors for AM, pathogen types, and treatments with statistical comparison using PearsonX2. Benefit of “targeted AFBC” for cases with high clinical suspicion was compared with “customary AFBC” in OR. Results: Thirty-one patients were identified with AM, of which 10 had one or more risk factors for AM, including foreign body (n = 4), non-HIV immune dysfunction (n = 4), and previous chemo-radiation (n = 4). Six different AM species were identified: most frequently M abscessus (50%), followed by M avium-intracellulare complex (20%) and M chelonae (17%). “Targeted AFBC” from outpatient setting were positive in 10 out of 190 (5.3%), whereas 10 out of 393 (2.5%) of “customary AFBC” in OR were positive ( P = .09). Macrolide therapy was employed in 16 out of 31 (52%) patients with AM-associated CRS but was not prescribed in patients with positive “customary AFBC” alone. Conclusion: AM-associated CRS is an uncommon condition that can occur in the absence of foreign body or overtly altered innate/adaptive immunity. Management with macrolide therapy, as well as the potential relationships between existence of AM in tap water, AM biofilms, and frequent nasal irrigations, warrant further investigation in refractory CRS.