Treatment of Nonpulmonary Infections Due to Mycobacterium fortuitum and Mycobacterium chelonei on the Basis of in Vitro Susceptibilities

Abstract

One hundred twenty-three patients with nonpulmonary infections due to Mycobacterium fortuitum or Mycobacterium chelonei were treated by wound debridement and with chemotherapy on the basis of in vitro susceptibilities of the organism. Of 76 patients with infections caused by M. fortuitum, 13 required no therapy or were adequately treated with surgery alone. Patients with active localized disease received single drug therapy (usually with a sulfonamide) for a mean period of 10.6 weeks for cellulitis and seven months for osteomyelitis. Patients with extensive disease received amikacin or amikacin plus cefoxitin (mean, four weeks) followed by a sulfonamide (mean, six months). The 47 patients with infections caused by M. chelonei received no therapy or were treated with surgery alone (6); with amikacin (10), erythromycin (6), doxycycline (3), or cefoxitin (1); or with amikacin plus cefoxitin followed by cefoxitin alone for a total of 10-12 weeks (20); or other multiple-drug regimens (1). Surgery was performed on 74 (60%) patients. Schlichter tests or serum drug levels were determined for 81 (66%) patients. Response to therapy was excellent; 68 (90%) infections with M. fortuitum and 34 (72%) with M. chelonei were successfully treated. Cultures became negative within six weeks of chemotherapy, except for sternal osteomyelitis, for which cultures were not negative until up to 14 weeks. Follow-up for a mean period of 12 months following therapy was possible in 80% of cases. Relapses were rare except in patients with disseminated disease, and drug resistance developed in only one patient. These studies demonstrate the value of routine susceptibility testing of these mycobacterial species and the benefit of chemotherapy on the basis of in vitro susceptibilities.

Pleural effusion in an immunocompetent woman caused by Mycobacterium fortuitum

“…However, M. fortuitum infrequently causes pulmonary disease and basal pleural disease with effusion is rare, despite the fact that M. fortuitum is often described as a commensal pathogen of the respiratory tract (Hand & Sanford, 1970). M. fortuitum in the pulmonary tissue can, however, cause pneumonia, empyema (Wallace et al, 1985) and abscess (Vadakekalam & Ward, 1991), although, when pulmonary infection occurs, it is usually superimposed onto a pre-existing lung disease, such as tuberculosis (Ichiyama & Tsukamura, 1987;Nussbaum & Heseltine, 1990); bronchiectasis, cystic fibrosis, pneumoconiosis or pulmonary alveolar proteinosis (Wallace et al, 1983); chronic obstructive pulmonary disease (Lessing & Walker, 1993); exogenous lipoid pneumonia (Jouannic et al, 1996); or parapneumonic pleurisy (Smith et al, 2001). One case of renal infection by M. fortuitum was described by Serra et al (2007).…”

Atypical Mycobacteria: an Unusual Cause of Breast Abscess

“…We also recommend outpatient repeated aspirations and long-term (four to six weeks) parenteral aminoglycoside for the initial treatment of atypical mycobacterial breast sepsis. Although surgical excision is the mainstay of treatment for soft tissue infections caused by M. chelonei, 12 it is indicated for abscesses failing to respond to medical treatment and repeated aspiration, poor patient compliance to antimycobacterial therapy and if mammillary fistula develops. In the absence of viable mycobacteria, the majority of fistulae, if they occur, will close spontaneously and a period of conservative treatment is justified.…”

Disseminated Mycobacterium chelonae Infection Presenting as Progressive Multifocal Osteomyelitis: Report of Two Cases and a Review of the Literature

“…Other entities associated with this organism include pulmonary disease (2,(15)(16)(17). prosthetic valve endocarditis (18). keratitis (18), osteomyelitis (18), and disseminated disease (2,6-8, 18-2 1).…”

“…prosthetic valve endocarditis (18). keratitis (18), osteomyelitis (18), and disseminated disease (2,6-8, 18-2 1).…”

“…Although the diagnosis of osteomyelitis was based on clinical gro].lnds without biopsy, Wallace et al have shown a very strong relationship between a clinical diagnosis , based on the presence of bony erosion adjacent to the site of a soft tissue infection, and the pathological diagnosis (2). Osteomyelitis due to this organism pas been well described in patients with local cutaneous disease as a result of direct extension (18); however, there have been few reports of bony involvement associated with disseminated disease. In fact, Wallace et al reported only two of 53 cases of disseminated infections due to M chelonae who had an associated osteomyelitis (6).…”