Humans ; Retrospective Studies ; Bronchiectasis ; Mycobacterium avium Complex ; Syndrome ; Nocardia Infections/drug therapy* ; Nocardia ; Mycobacterium avium-intracellulare Infection

OBJECTIVEMycobacterium avium (M. avium) and Mycobacterium intracellulare (M. intracellulare) are the major causative agents of nontuberculous mycobacteria (NTM)-related pulmonary infections. However, little is known about the differences in drug susceptibility profiles between these two species.

METHODSA total of 393 NTM isolates were collected from Shanghai Pulmonary Disease Hospital. Sequencing of partial genes was performed to identify the strains at species level. The minimum inhibitory concentration (MIC) was used to evaluate the drug susceptibility against 20 antimicrobial agents. Variable number of tandem repeat (VNTR) typing was conducted to genotype these two species.

RESULTSA total of 173 (44.0%) M. avium complex (MAC) isolates were identified, including 41 (10.4%) M. avium isolates and 132 (33.6%) M. intracellulare isolates. Clarithromycin and amikacin were the two most effective agents against MAC isolates. The Hunter-Gaston Discriminatory Index (HGDI) values for VNTR typing of M. avium and M. intracellulare isolates were 0.993 and 0.995, respectively. Levofloxacin resistance was more common among the unclustered strains than among the clustered strains of M. intracellulare.

CONCLUSIONM. intracellulare was the most common NTM species in China. Clarithromycin and amikacin had high antimicrobial activities against MAC. VNTR typing of MAC isolates revealed a high discriminatory power. Levofloxacin resistance was associated with unclustered strains of M. intracellulare.

Anti-Bacterial Agents ; pharmacology ; Drug Resistance, Bacterial ; Genotype ; Humans ; Mycobacterium avium Complex ; drug effects ; genetics ; Mycobacterium avium-intracellulare Infection ; epidemiology ; microbiology

Mycobacterium avium complex (MAC) comprises M. intracellulare and M. avium. MAC usually causes pulmonary diseases in individuals with intact immunity, disseminated disease in patients with acquired immunodeficiency syndrome, and cervical lymphadenitis. It can also cause cutaneous disease, but musculoskeletal infection is rare. Herein, we present a case of vertebral osteomyelitis due to M. intracellulare in an elderly immunocompetent patient who underwent vertebroplasty. The patient was successfully treated with antimycobacterial drugs without surgical intervention. MAC should be considered as a causative pathogen of vertebral osteomyelitis when the patient has a history of vertebroplasty.
Acquired Immunodeficiency Syndrome ; Aged* ; Humans ; Lung Diseases ; Lymphadenitis ; Mycobacterium avium Complex* ; Mycobacterium avium-intracellulare Infection ; Mycobacterium* ; Nontuberculous Mycobacteria ; Osteomyelitis* ; Vertebroplasty*

OBJECTIVE: To determine the patho-mechanism of pleural effusion or hydropneumothorax in Mycobacterium avium complex (MAC) lung disease through the computed tomographic (CT) findings. MATERIALS AND METHODS: We retrospectively collected data from 5 patients who had pleural fluid samples that were culture-positive for MAC between January 2001 and December 2013. The clinical findings were investigated and the radiological findings on chest CT were reviewed by 2 radiologists. RESULTS: The 5 patients were all male with a median age of 77 and all had underlying comorbid conditions. Pleural fluid analysis revealed a wide range of white blood cell counts (410-100690/microL). The causative microorganisms were determined as Mycobacterium avium and Mycobacterium intracellulare in 1 and 4 patients, respectively. Radiologically, the peripheral portion of the involved lung demonstrated fibro-bullous changes or cavitary lesions causing lung destruction, reflecting the chronic, insidious nature of MAC lung disease. All patients had broncho-pleural fistulas (BPFs) and pneumothorax was accompanied with pleural effusion. CONCLUSION: In patients with underlying MAC lung disease who present with pleural effusion, the presence of BPFs and pleural air on CT imaging are indicative that spread of MAC infection is the cause of the effusion.
Aged ; Aged, 80 and over ; Female ; Fistula/complications ; Humans ; Hydropneumothorax/complications/microbiology/*radiography ; Lung/radiography ; Male ; Middle Aged ; Mycobacterium avium/*isolation & purification ; Mycobacterium avium Complex/isolation & purification ; Mycobacterium avium-intracellulare Infection/*diagnosis/microbiology ; Pleural Diseases/complications/microbiology/*radiography ; Pleural Effusion/complications ; Retrospective Studies ; *Tomography, X-Ray Computed

Brown-Sequard Syndrome ; diagnosis ; Diagnosis, Differential ; HIV Infections ; complications ; Humans ; Male ; Middle Aged ; Mycobacterium avium-intracellulare Infection ; diagnosis

We report a very rare case of a bronchogenic cyst combined with nontuberculous mycobacterial pulmonary disease in an immunocompetent patient. A 21-year-old male was referred to our institution because of a cough, fever, and worsening of abnormalities on his chest radiograph, despite anti-tuberculosis treatment. Computed tomography of the chest showed a large multi-cystic mass over the right-upper lobe. Pathological examination of the excised lobe showed a bronchogenic cyst combined with a destructive cavitary lesion with granulomatous inflammation. Microbiological culture of sputum and lung tissue yielded Mycobacterium avium. The patient was administered anti-mycobacterial treatment that included clarithromycin.
Anti-Bacterial Agents/therapeutic use ; Biopsy ; Bronchogenic Cyst/*complications/diagnosis/immunology/surgery ; Humans ; *Immunocompetence ; Male ; Mycobacterium avium Complex/*isolation & purification ; Mycobacterium avium-intracellulare Infection/*complications/diagnosis/drug therapy/immunology/microbiology ; Pneumonectomy ; Respiratory Tract Infections/*complications/diagnosis/drug therapy/immunology/microbiology ; Sputum/microbiology ; Tomography, X-Ray Computed ; Treatment Outcome ; Young Adult

Disseminated Mycobacterium avium complex (MAC) infection can occur in immunocompromised patients, and rarely in immunocompetent subjects. Due to the extensive distribution of the disease, clinical presentation of disseminated MAC may mimic malignancies, and thorough examinations are required in order to make accurate diagnosis. We report a case of disseminated Mycobacterium intracellulare disease in an immunocompetent patient, which involved the lung, lymph nodes, spleen, and multiple bones. F-18 fluorodeoxyglucose positron-emission tomography imaging showed multiple hypermetabolic lesions, which are suggestive of typical hematogenous metastasis. However, there was no evidence of malignancy in serial biopsies, and M. intracellulare was repeatedly cultured from respiratory specimens and bones. Herein, we should know that disseminated infection can occur in the immunocompetent subjects, and it can mimic malignancies.
Biopsy ; Humans ; Hybridization, Genetic ; Hydrazines ; Immunocompetence ; Immunocompromised Host ; Lung ; Lymph Nodes ; Mycobacterium ; Mycobacterium avium Complex ; Mycobacterium avium-intracellulare Infection ; Neoplasm Metastasis ; Nontuberculous Mycobacteria ; Positron-Emission Tomography ; Spleen

While nontuberculous mycobacterium (NTM) infections are recently on the rise, arthritis caused by NTM is hardly reported in Korea. NTM arthritis has no distinctive clinical characteristics from chronic arthritis. Tuberculosis of the joint specifically produces similar clinical and pathologic presentations to NTM arthritis, so it is not easy to distinguish between them. We report a case of Mycobacterium intracellulare in an arthritis patient after trauma and surgical repair of the injury. At the beginning, the patient was diagnosed as tuberculous tenosynovitis through pathology without microbiologic evidence. The final diagnosis was made after subsequent recurrences for several years. The misdiagnosis and delayed diagnosis led to irreversible joint destruction and functional impairment. NTM infection must be included in the differential diagnosis of chronic arthritis at the outset.
Arthritis ; Delayed Diagnosis ; Diagnosis, Differential ; Diagnostic Errors ; Humans ; Joints ; Korea ; Mycobacterium ; Mycobacterium avium Complex ; Mycobacterium avium-intracellulare Infection ; Nontuberculous Mycobacteria ; Recurrence ; Tenosynovitis ; Tuberculosis

Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Face ; microbiology ; Female ; Humans ; Middle Aged ; Mycobacterium avium Complex ; isolation & purification ; Mycobacterium avium-intracellulare Infection ; metabolism ; microbiology ; pathology ; Nasal Cavity ; microbiology ; Nose Diseases ; metabolism ; microbiology ; pathology ; Vimentin ; metabolism

PURPOSE: PCR is widely used for rapidly and accurately detecting Mycobacterium Species. The purpose of this study was to assess the diagnostic performance of three real-time PCR kits and evaluate the concordance with two older PCR methods. MATERIALS AND METHODS: Using 128 samples, the five PCR methods were assessed, including an in-house PCR protocol, the COBAS Amplicor MTB, the COBAS TaqMan MTB, the AdvanSure TB/NTM real-time PCR, and the Real-Q M. tuberculosis kit. The discrepant results were further examined by DNA sequencing and using the AdvanSure Mycobacteria Genotyping Chip for complete analysis. RESULTS: For Mycobacterium tuberculosis (MTB) detection, all five kits showed 100% matching results (positive; N = 11 and negative; N = 80). In non-tuberculous mycobacterium (NTM) discrimination, the AdvanSure yielded two true-positive outcomes from M. intracellulare and one false positive outcome, while the Real-Q resulted in one true-positive outcome and one false negative outcome for each case and another false negative result using the provided DNA samples. CONCLUSION: Real-time PCR, yielded results that were comparable to those of the older PCR methods for detecting MTB. However, there were disagreements among the applied kits in regard to the sample test results for detecting NTM. Therefore, we recommend that additional confirmatory measures such as DNA sequencing should be implemented in such cases, and further research with using a larger numbers of samples is warranted to improve the detection of NTM.
DNA, Bacterial/genetics ; Humans ; Mycobacterium/*genetics ; Mycobacterium Infections/*diagnosis/microbiology ; Mycobacterium avium Complex/genetics ; Mycobacterium avium-intracellulare Infection/diagnosis ; Mycobacterium tuberculosis/genetics ; Polymerase Chain Reaction/*standards ; Reagent Kits, Diagnostic/*standards ; Tuberculosis/diagnosis