The Talking Mycobacterium abscessus Blues

I thought I knew what was happening, but then again, maybe I don’t. In 1993 we published our experience with 120 patients who had Mycobacterium abscessus lung disease [1]. Patients were followed up for an average of almost 5 years and received various antimicrobial agents including, amikacin, cefoxitin, erythromycin (most patients were treated prior to the availability of clarithromycin), or sulfonamides. Only 10 patients (8%) with M. abscessus lung disease were cured as defined by return of respiratory symptoms to baseline and reversion of sputum to AFB culture negative for at least 1 year. Of the 10 patients in whom M. abscessus was cured, 7 received amikacin and cefoxitin or imipenem followed by surgical excision, whereas only 3 subjects were successfully treated with antibiotics alone. Eighteen patients (15%) died as direct result of their lung disease. In the interval between 1993 and 2010, few new studies were published that addressed the treatment of M. abscessus lung disease. In this issue of the Journal, however, Jarand et al [2] present a retrospective analysis of treatment outcomes for 107 patients with M. abscessus pulmonary disease from 2001 to 2008. Sixty-four percent of the patients were followed up for an average of 34 months. Antibiotic treatment was individualized based on drug susceptibility results and patient tolerance. Sixteen different antibiotics were used in 42 different combinations for an average of 4.6 drugs per patient over the course of therapy with a median of 6 intravenous antibiotic months. At least 1 drug was stopped due to side effects or toxicity in the majority of patients, most commonly amikacin or cefoxitin. Twenty-four patients had surgery in addition to medical therapy. Forty-nine patients converted sputum cultures to negative, but 16 relapsed. There were significantly more surgical patients who culture converted compared with medical patients. Seventeen (15.9%) deaths occurred in the study population. Jeon et al [3] also recently published the results of antibiotic treatment for 65 patients with M. abscessus lung disease. Patients were initially hospitalized and treated with 4 weeks of parenteral amikacin and cefoxitin in combination with oral drugs including clarithromycin, ciprofloxacin, and doxycylcline. Patients tolerated the cefoxitin for only an average of 22 days. Sputum conversion and maintenance of negative sputum cultures for more than 12 months was achieved in 58% patients. Surgical resection was performed in 22% patients. Seven (88%) of 8 patients with preoperative culture positive sputum achieved and maintained culture negativity postoperatively. Treatment success was associated with in vitro susceptibility to clarithromycin, but not with any of the other antimicrobial agents used. This study has several attractive aspects, including a standard treatment protocol for a relatively large group of M. abscessus lung disease patients. It is also seductive, in that it offers an almost completely oral regimen as an alternative to the more intensive traditional combination regimens that include prolonged parenteral therapy such as the regimens used in the study by Jarand et al [2].