Nontuberculous mycobacteria in cystic fibrosis associated with allergic bronchopulmonary aspergillosis and steroid therapy

Abstract

Nontuberculous mycobacterial (NTM) infection, particularly due to Mycobacterium abscessus, is an emerging disease that can be relentlessly progressive, particularly in cystic fibrosis (CF) patients. The risk factors that were associated with this increasingly symptomatic infection in a group of CF patients were investigated.A total of 139 CF patients aged 2-52 yrs were reviewed. Sputum was cultured for NTM annually or whenever clinical deterioration was unexplained.In total, 12 patients (8.6%) had positive cultures and six (4.3%) met the criteria for NTM pulmonary disease (five with M. abscessus). Five had allergic bronchopulmonary aspergillosis (ABPA) compared with one out of 133 patients without NTM disease. Five had received systemic steroids (four as a treatment for ABPA) compared with only one out of 133 without NTM lung disease. All six NTM patients deteriorated markedly following mycobacterial infection, and forced expiratory volume in one second dropped 18-46%. Despite prolonged triple antibiotic therapy, M. abscessus was not eradicated, and four out of six did not return to baseline clinically.In conclusion, severe nontuberculous mycobacterial lung disease, particularly with Mycobacterium abscessus, is becoming a perplexing challenge in cystic fibrosis patients. Allergic bronchopulmonary aspergillosis and systemic steroids appear to be risk factors, although small patient numbers limit this to a descriptive observation. When pulmonary condition deteriorates, increased surveillance for mycobacteria would enable prompt diagnosis and treatment.KEYWORDS: Allergic bronchopulmonary aspergillosis, cystic fibrosis, Mycobacterium abscessus, nontuberculous mycobacteria, pulmonary infection, steroid therapy L ife expectancy and quality of life have been improving steadily in cystic fibrosis (CF), as treatment regimens become more aggressive. Concomitantly, reports describe the rising incidence of unusual pulmonary pathogens in CF, including Stenotrophomonas maltophilia, Alkaligenes xyloxidans, Nocardia and nontuberculous mycobacteria (NTM) [1]. Recently, there has been increasing concern about the potential pulmonary pathogenicity of NTM in CF [2]. At least 12 single-site studies described a total population of ,1,300 CF patients, with an NTM prevalence varying 2-28% [3][4][5][6][7][8][9].A USA multicentre study of 986 CF patients aged .10 yrs showed a 13% NTM prevalence [10], and 16% of these had Mycobacterium abscessus (previously M. chelonae, subspecies abscessus). Although the clinical course appeared relatively benign [11], an editorial comment [12] emphasised that all NTM isolates were considered together as potential pathogens, and the majority were M. avium complex. Focusing on more virulent pathogens, such as M. abscessus, might accentuate important differences in prognosis, but small numbers probably precluded this. In contrast, a French study [7] described M. abscessus as the most prevalent NTM by far, particularly in younger CF patients.Recently, the current authors have encountered CF patien...

Changing Epidemiology of the Respiratory Bacteriology of Patients With Cystic Fibrosis

“…6 Increases in MRSA, [7][8][9] A xylosoxidans, 8,10,11 and S maltophilia 8,9,12 have also been reported. The prevalence of nontuberculous mycobacteria (NTM) varies by age and by country, but has been increasing [13][14][15][16] particularly for Mycobacterium abscessus. 17,18 However, determining epidemiologic trends in CF microbiology can be challenging because of lack of reliable historical data for some pathogens; changes in reporting strategies; variations in sampling methods, microbiologic techniques, and culture frequency; and the patient population studied.…”

Nontuberculous mycobacterial disease and Aspergillus-related lung disease in bronchiectasis

“…Patients with chronic lung disease are also prone to Aspergillus colonisation and infection [3]. Cystic fibrosis (CF) and NTM infection may be associated with allergic bronchopulmonary aspergillosis (ABPA) and steroid therapy [4].…”

Allergic Bronchopulmonary Aspergillosis with Repeated Isolation of Nontuberculous Mycobacteria

“…To date, several ABPA patients in whom NTM was isolated have been reported (12)(13)(14)(15)(16). The isolation of NTM can indicate the presence of both infection and simple colonization.…”

“…The isolation of NTM can indicate the presence of both infection and simple colonization. Most previous reports differentiated NTM infection from simple colonization (13,16) according to the ATS/IDSA criteria (12). Mussaffi et al reported that six of 139 cystic fibrosis patients had ABPA, four of whom developed concomitant NTM infection following the diagnosis of ABPA (13).…”

“…Most previous reports differentiated NTM infection from simple colonization (13,16) according to the ATS/IDSA criteria (12). Mussaffi et al reported that six of 139 cystic fibrosis patients had ABPA, four of whom developed concomitant NTM infection following the diagnosis of ABPA (13). In some reports (14,15), NTM infection was differentiated from colonization based on histologic findings.…”