A case of endobronchial lesion due to infection with Mycobacterium intracellulare

A 53-year-old man was hospitalized in April 2001 because of left cervical lymphadenopathy and a mass shadow in the left lingular segment. Bronchoscopy revealed an elevated lesion in the left main bronchus, but a biopsy showed no specific findings. A left cervical lymph node biopsy revealed lymphoid hyperplasia only and no malignancy. After the patient was discharged, bronchial irrigation solution from the left lingular segment was found to be positive for Mycobacterium intracellulare. In July 2001 the shadow in the left lingular segment had worsened, and bronchoscopy was performed again. This revealed ulceration in the left main bronchus and edematous narrowing of the bronchial lumen at the opening of the lingular segment. A granulated lesion accompained by severe inflammation was seen in a biopsied specimen taken from the same site. Bronchial lesion induced by an acid-fast-stain positive nontuberculosis mycobacteria was noted. Treatment with rifampicin (RFP), clarithromycin (CAM), ethambutol (EB), and streptomycin (SM) was started, but a rash most likely caused by RFP developed, and RFP was replaced by ciprofloxacin (CPFX). The treatment was continued and symptoms improved. Since non-tuberculous mycobacteriosis accompanied with bronchial lesions is rare, a case report was made.     

A case of pulmonary mycobacterium intracellulare infection complicated with pneumothorax and pleurisy

A 74 year-old female complaining of increased cough and sputum was admitted to our hospital on June 14th 2004. She had been diagnosed as Mycobacterium intracellulare (M. intracellurare) infection since 2002 and had been treated from March to October 2003 in the Department of General Medicine in our hospital. Chest CT on admission showed diffuse small nodular shadows in the lung, a cavity, pneumothorax, and pleural effusion in the right lung. The sputum smear was positive for acid-fast bacilli and sputum PCR examination was positive for M. intracellulare. She was diagnosed as the recurrence of non-tuberculous mycobacterium (NTM) infection and treatment of NTM infection was started. No other infections were suspected and the pneumothorax and pleural effusion gradually improved with the treatment. We concluded that the pneumothorax and pleural effusion were caused by NTM infection. Since pneumothorax is an extremely rare complication in NTM infections we thought it is worth-while to report our case.     

A case of Mycobacterium scrofulaceum lung infection occurring in old lung tuberculosis lesion

A 68-year-old man was admitted because of a persistent productive cough of 6 weeks' duration and detection of acid-fast bacilli from sputum. Based on chest roentgenograms and isolation of Mycobacterium scrofulaceum from sputum, on admission, a diagnosis of Mycobacterium scrofulaceum lung infection was made. Although the organisms were resistant to 0.1 microgram/ml of INH, 2.5 micrograms/ml of EB and 10 micrograms/ml of RFP, sputum converted to negative by the use of INH (0.4 g/day), EB (0.5 g/day) and RFP (0.3 g/day) for 2 months. The incidence rate of nontuberculous lung mycobacteriosis seems to be increasing recently. This is partially considered to be due to an increase of various strains of nontuberculous mycobacteria in the environment. A striking advance of clinical medicine and changes in the constitution of human society and environment surrounding us produce an increase in the number of compromised hosts. The lung disease due to Mycobacterium scrofulaceum, a kind of opportunistic pathogen, is considered to be increasing in a wide variety of compromised hosts in the future.     

A case of Mycobacterium intracellulare infection with chronic empyema

A 83-year-old man had been treated for pulmonary infiltration was referred to a nearby hospital because of slight fever and cough. His chest radiograph and CT showed right chronic empyema, and in which pleural aspirate was smear positive for acid-fast bacilli and positive for PCR-Mycobacterium intracellulare. He was diagnosed as chronic empyema caused by M. intracellulare. A month later exacerbation of bronchopleural fistula was observed and M. intracellulare infection expanded into the lung. He was treated with combined use of ethambutol, rifampicin, clarithromycin, and streptomycin for six months, and his chest radiograph showed improvement, however, finally he died as he was in advanced age and emaciation due to chronic lung infection.     

A case of Mycobacterium intracellulare pulmonary infection with vertebral osteomyelitis

A 78-year-old woman seen in June 2005 for chest abnormal shadows after 3 months of steroid therapy for vasculitis associated with antineutrophil cytoplasmic autoantibodies was found in chest computed tomography (CT) revealed bronchiectasis and small nodules in the right middle lobe and left lingula. Sputum cultures were positive for Mycobacterium intracellulare. Based on a diagnosis of pulmonary nontuberculous mycobacteriosis, the woman underwent antimycobacterial therapy with clarithromycin, rifampicin, and ethambutol hydrochloride for 10 months. She was then admitted in June 2009 with right chest pain. Chest CT showed consolidation shadows with bronchiectasis in the right middle lobe and the left lingula and left pleural effusion. Magnetic resonance imaging (MRI) showed that Th7-Th8 vertebral bodies had collapsed. A vertebral body specimen obtained by CT-guided biopsy was positive for M. intracellulare. Based on a diagnosis of vertebral osteomyelitis due to M. intracellulare, she underwent antimycobacterial therapy with clarithromycin (800 mg), rifampicin (450 mg), ethambutol hydrochloride (750 mg), and streptomycin (750 mg). After 4 weeks of antimycobacterial therapy, she underwent radical debridement and decompression surgery with anterior and posterior spinal fusion. Four weeks postoperatively, streptomycin was discontinued. We continued clarithromycin, rifampicin, and ethambutol hydrochloride for 18 months, and no recurrence was detected. Although vertebral osteomyelitis due to nontuberculous mycobacteria is rare, clinicians should consider the combination of nontuberculous mycobacteriosis and vertebral osteomyelitis in cases such at these.     

A case of pulmonary Mycobacterium scrofulaceum infection presented as pleurisy

A 68-year-old man was referred to our hospital for further examination of pleurisy. Before this admissions, he was diagnosed as having tuberculous pleurisy initially and later as having pleurisy due to SLE in another hospital. He was administered anti-tuberculous medicine including INH, RFP and EB empirically, and later prednisolone and azathioprine. Despite of these medications, there was no improvement. After admission to our hospital, positive results for acid fast bacilli were obtained from both sputum and pleural fluid, and they were identified as Mycobacterium scrofulaceum. He was treated successfully with the combination of INH, RFP, EB plus SM and CAM. The expectoration of M. scrofulaceum was ceased after 4 months of treatment. The common lesion of non-tuberculous mycobacterium is found in the lung. A non-tuberculous mycobacterium infection might accompany with pleural involvement or pleurisy. Thus in case of pleural diseases, non-tuberculous mycobacterium should also be included among differential diagnosis.     

A case of Mycobacterium intracellulare infection complicated by immotile cilia syndrome]

A 25-year-old woman with a history of immotile cilia syndrome (ICS) was admitted to our hospital with dyspnea. Chest roentgenography revealed dense infiltrates in both lower lung fields in addition to bronchiectasis and small nodular opacities, which had been observed previously. Transbronchial lung biopsy demonstrated evidence of non-caseating epithelioid cell granuloma. Sputum specimens were examined, and isolates were identified as Mycobacterium intracellulare. The patient was given antituberculous therapy and clarithromycin, which induced clinical improvement. It is well known that bronchial mucociliary transport is severely impaired in patients with ICS. However, to our knowledge, cases of M. intracellulare infection complicated by ICS have not been reported in Japan. We must pay close attention to the concurrence of these diseases.     

Mycobacterium intracellulare pulmonary infection which co-existed and mimicked lung cancer

We report a case of Mycobacterium intracellulare (M. intracellulare) pulmonary infection with co-existing lung cancer and presenting as a solitary pulmonary nodule requiring differentiation from lung cancer. Computed tomography showed two nodules (20 mm) with spicula formation and pleural indentation on the right lower lobe of the lung (right S6 and S8). Transbronchial biopsies from the right S6 and S8 nodules revealed mycobacteriosis and adenocarcinoma, respectively. Thereafter, a right lower lobectomy was performed. Cases of pulmonary M. intracellulare disease with solitary nodule are rare. Moreover, M. intracellulare pulmonary infection with co-existing lung cancer is extremely rare.     

A case of Mycobacterium intracellulare lung disease occurred in a middle-aged man who complained hemoptysis with normal chest roentogenogram

A 45-year-old man visited our clinic because of intermittent bloody sputum. The chest roentogenogram was normal, but the high-resolution computed tomography (HRCT) showed very small nodules and bronchiolitis adjacent to pleura in the upper right lung field. The bronchoscopic examination revealed blood-streaked bronchial secretion in the right upper lobe bronchus, and the cultures of the sputa and the bronchial washing specimen showed acid-fast bacilli identified as Mycobacterium intracellulare by DNA-DNA hybridization (DDH) method. This case was diagnosed as Mycobacterium intracellulare lung disease. The patient received isoniazid, levofloxacin, and clarithromycin for three years without clinical and bacteriological improvement. His hemoptysis and the number of colonies recovered from sputum cultures decreased without any medication later. The serial chest roentogenograms and HRCTs have showed no changes for 6 years after the diagnosis. This case may show some clues to elucidate the mechanism of the onset of Mycobacterium intracellulare lung disease without predisposing conditions.     

A case of pulmonary Mycobacterium intracellulare infectious disease with a solitary pulmonary nodule in the peripheral lung field]

A 63-year-old woman was admitted to our hospital because of a solitary nodule (20 x 20 mm) in the right S3 which was first detected during a health examination. Because radiological findings for the nodule, such as pleural indentation and spicula on chest CT led us to suspect a pulmonary adenocarcinoma, we could not completely rule out lung cancer and performed a bronchoscopic examination on the third day after admission. However, no definite diagnosis could be made. Therefore, video-assisted thoracic surgery (VATS) was performed, and a caseating epitheloid granuloma with acid-fast bacilli was found. Initially, we administered antituberculous drugs for pulmonary tuberculoma, but then changed to combined chemotherapy using RFP, EB, CAM and SM after identification of Mycobacterium intracellulare by a culture test of resected tissue. We report a rare case with a solitary nodule caused by pulmonary Mycobacterium intracellulare infectious disease which is indicative of lung cancer.     

Enzymatic profile of Mycobacterium avium and Mycobacterium intracellulare

The characterization of extracellular enzymatic activities of Mycobacterium avium and Mycobacterium intracellulare which were identified by DNA probe (Gen-Probe, Cal., USA) was carried out using the API ZYM system (API, La Balme Les Grottes, France). The enzymatic activities of M. avium were attributed to esterase (C4), esterase lipase (C8), leucin arylamidase, acid phosphatase and phosphoamidase. Enzymatic characterization of M. intracellulare was very similar to that of M. avium. However, M. intracellulare differed from M. avium in the following two points: (i) Alkaline phosphatase activity was demonstrated, (ii) Acid phosphatase activity was much stronger.     

Clinical significance and epidemiologic analyses of Mycobacterium avium and Mycobacterium intracellulare lung disease from post-marketing surveillance

Background

In Japan, nontuberculous mycobacterial lung disease is mostly attributable to Mycobacterium avium complex (MAC), i.e., M. avium or M. intracellulare. However, clinical features of the disease caused by these two pathogens have not been studied sufficiently yet.

Changes of the biotype of Mycobacterium avium-Mycobacterium intracellulare complex causing lung disease in Japan

A survey was carried out on the biological and biochemical characteristics of 661 strains of Mycobacterium avium-M. intracellulare complex that caused lung disease in the period 1976 to 1986. The results showed that the proportion of strains which showed 2-week-arylsulphatase activity and that of those which were able to utilize glucose as sole carbon source in the presence of glutamate-nitrogen decreased markedly, and that the proportion of those which utilized neither n-butanol nor iso-butanol as sole carbon sources in the presence of ammoniacal nitrogen increased markedly over these 11 years. These findings indicate that the predominant biotype changed from M. intracellulare to M. avium during the period under study. This postulate is supported by a limited study of the serovars present among the isolates.     

Antimicrobial susceptibility and genotyping of Mycobacterium intracellulare

正Objective To investigate the antimicrobial susceptibility and genotyping of Mycobacterium intracellulare.Methods A total of 150M. intracellulareisolates were collected. The susceptibility against 15 antimicrobial agents widely used for treatment of non-tuberculosis mycobacteria (NTM) infections, was tested by broth microdilution assay. Variable number of tandem repeats(VNTR) assay was also performed using the 16-loci genotyping method.ResultsThe drug susceptibility test re-     

Susceptibility of Mycobacterium intracellulare to hydrogen peroxide

The susceptibility to H2O2 of 5 strains of Mycobacterium intracellulare and both catalase-positive (TMC 102) and negative (TMC 303) strains of M. tuberculosis, H37RV, was tested at pH 7.0 and 4.0. All strains of M. intracellulare were significantly more resistant to this oxygen metabolite than were the two M. tuberculosis strains, even though the catalase activity of M. tuberculosis TMC 102 was higher than most M. intracellulare strains. Even the catalase negative (Eggeman) strain of M. intracellulare showed greater resistance to 0.2% H2O2 than M. tuberculosis H37RV (TMC 102). This suggests that M. intracellulare is protected from H2O2 damage by factors additional to their catalase activity.