Clinical characteristics and prognostic factors of non-tuberculous mycobacterial disease in patients with rheumatoid arthritis

BACKGROUND/AIMS

This study aimed to identify the clinical characteristics of patients with concurrent rheumatoid arthritis (RA) and suspected non-tuberculous mycobacterial (NTM) infections as well as determine their prognostic factors.

METHODS

We retrospectively reviewed the medical records of 91 patients with RA whose computed tomography (CT) findings suggested NTM infection. Subsequently, we compared the clinical characteristics between patients with and without clinical or radiological exacerbation of NTM-pulmonary disease (PD) and investigated the risk factors for the exacerbation and associated mortality.

RESULTS

The mean age of patients with RA and suspected NTM-PD was 65.0 ± 10.2 years. The nodular/bronchiectatic (NB) form of NTM-PD was the predominant radiographic feature (78.0%). During follow-up, 36 patients (41.9%) experienced a radiological or clinical exacerbation of NTM-PD, whereas 12 patients (13.2%) died. Combined interstitial lung disease (ILD), microbiologically confirmed NTM-PD, and NB with the fibrocavitary (FC) form on chest CT were identified as risk factors for the clinical or radiological exacerbation of NTM-PD. Hydroxychloroquine use was identified as a good prognostic factor. Conversely, history of tuberculosis, ILD, smoking, microbiologically confirmed NTM-PD, and NB with the FC form on chest CT were identified as poor prognostic factors for mortality in suspected NTM-PD.

CONCLUSION

ILD and NB with the FC form on chest CT were associated with NTM-PD exacerbation and mortality. Hydroxychloroquine use may lower the risk of NTM-PD exacerbation. Therefore, radiographic features and presence of ILD should be considered when predicting the prognosis of patients with RA and suspected NTM-PD.

Clinical Impact of Chronic Pulmonary Aspergillosis in Patients with Nontuberculous Mycobacterial Pulmonary Disease and Role of Computed Tomography in the Diagnosis

Objective Chronic pulmonary aspergillosis (CPA) is an important complication of nontuberculous mycobacterial pulmonary disease (NTM-PD). However, its diagnosis is challenging, as both CPA and NTM-PD present as chronic cavitary disease. The present study evaluated the impact of CPA on the survival of patients with NTM-PD and revealed the key computed tomography findings for a prompt diagnosis. Methods We retrospectively reviewed patients newly diagnosed with NTM-PD in Tenri Hospital (Tenri City, Nara Prefecture, Japan) between January 2009 and March 2018; the patients were followed up until May 2021. Clinical and radiological characteristics were assessed, and patients with CPA were identified. Results A total of 611 patients were diagnosed with NTM-PD. Among them, 38 (6.2%), 102 (17%), and 471 (77%) patients were diagnosed with NTM-PD with CPA, cavitary NTM-PD without CPA, and non-cavitary NTM-PD without CPA, respectively. The 5-year survival rate of the NTM-PD with CPA group (42.8%; 95% confidence interval: 28.7-64.0%) was lower than that of the cavitary NTM-PD without CPA group (74.4%; 95% confidence interval: 65.4-84.6%). A multivariate analysis revealed that fungal balls and cavities with adjacent extrapleural fat were significant predictive factors for NTM-PD with CPA. Conclusion NTM-PD with CPA patients exhibited a worse prognosis than cavitary NTM-PD without CPA patients. Therefore, an unerring diagnosis of CPA is essential for managing patients with NTM-PD. Computed tomography findings, such as fungal balls and cavities with adjacent extrapleural fat, may be valuable diagnostic clues when CPA is suspected in patients with NTM-PD.

Building a model for the differential diagnosis of non-tuberculous mycobacterial lung disease and pulmonary tuberculosis: A case-control study based on immunological and radiological features

BACKGROUND

Although the incidence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing annually, it is easily misdiagnosed as pulmonary tuberculosis (PTB). This study aimed to screen and identify the immunological and radiological characteristics that differentiate NTM-PD from PTB and to construct a discriminatory diagnostic model for NTM-PD, providing new tools for its differential diagnosis.

METHODS

Hospitalised patients diagnosed with NTM-PD or PTB between January 2019 and June 2023 were included in the study. Immunological and radiological characteristics were compared between the two groups. Based on the selected differential features, a logistic regression algorithm was used to construct a discriminatory diagnostic model for NTM-PD, and its diagnostic performance was preliminarily analysed.

RESULTS

Patients with NTM-PD were significantly older than those with PTB and the tuberculosis-specific interferon-gamma release assay (TB-IGRA) positivity rate was significantly lower in the NTM-PD group. Moreover, the absolute counts of total T lymphocytes, CD4+ T lymphocytes, CD8+ T lymphocytes, NK cells, and B lymphocytes were significantly lower in patients with NTM-PD and PTB than in healthy controls. Additionally, patients with NTM-PD had a significantly lower absolute count of B lymphocytes than the PTB group. Radiological analysis revealed significant differences between patients with NTM-PD and PTB in terms of cavity wall thickness, bronchial dilation, lung consolidation, pulmonary nodule size, pulmonary emphysema, lung bullae, lymph node calcification, pleural effusion, mediastinal and hilar lymphadenopathy, and the tree-in-bud sign. Bronchial dilation was identified as the predominant risk factor of NTM-PD, whereas TB-IGRA positivity, lymph node calcification, pleural effusion, and mediastinal and hilar lymphadenopathies were protective factors. Based on this, we constructed a discriminatory diagnostic model for NTM-PD. Its receiver operating characteristic curve demonstrated good diagnostic performance, with an area under the curve of 0.938. At the maximum Youden index of 0.746, the sensitivity and specificity were 0.835 and 0.911, respectively.

CONCLUSIONS

Patients with NTM-PD and PTB exhibited impaired humoral and cellular immune functions as well as significant differences in radiological features. The constructed NTM-PD diagnostic model demonstrated good diagnostic performance. This study provides a new tool for the differential diagnosis of NTM-PD.

Lung infection with nontuberculous mycobacteria

OBJECTIVE

To describe the epidemiology and CT findings for nontuberculous mycobacterial lung infections and outcomes depending on the treatment.

MATERIAL AND METHODS

We retrospectively studied 131 consecutive patients with positive cultures for nontuberculous mycobacteria between 2005 and 2016. We selected those who met the criteria for nontuberculous mycobacterial lung infection. We analysed the epidemiologic data; clinical, microbiological, and radiological findings; treatment; and outcome according to treatment.

RESULTS

We included 34 patients (mean age, 55 y; 67.6% men); 50% were immunodepressed (58.8% of these were HIV+), 20.6% had COPD, 5.9% had known tumors, 5.9% had cystic fibrosis, and 29.4% had no comorbidities. We found that 20.6% had a history of tuberculosis and 20.6% were also infected with other microorganisms. Mycobacterium avium complex was the most frequently isolated germ (52.9%); 7 (20.6%) were also infected with other organisms. The most common CT findings were nodules (64.7%), tree-in-bud pattern (61.8%), centrilobular nodules (44.1 %), consolidations (41.2%), bronchiectasis (35.3%), and cavities (32.4%). We compared findings between men and women and between immunodepressed and immunocompetent patients. Treatment was antituberculosis drugs in 67.6% of patients (72% of whom showed improvement) and conventional antibiotics in 20.6% (all of whom showed radiologic improvement).

CONCLUSION

The diagnosis of nontuberculous mycobacterial lung infections is complex. The clinical and radiologic findings are nonspecific and a significant percentage of pateints can have other, concomitant infections.

Chest Computed Tomography Features of Nontuberculous Mycobacterial Pulmonary Disease Versus Asymptomatic Colonization: A Cross-sectional Cohort Study

BACKGROUND

Asymptomatic colonization by nontuberculous mycobacteria (NTM) found in sputum isolates are commonly encountered and clinicians lack a biomarker for prognosticating the risk of transition asymptomatic colonization to active clinical disease. Chest computed tomography (CT) imaging is commonly obtained in this patient population and may serve a role for this purpose.

METHODS

We conducted a single-center, cross-sectional study of patients followed in the NTM clinic at our center between August 2019 and August 2020. All patients had a history of NTM isolated from their airways and were cohorted as either nontuberculous mycobacteria-pulmonary disease (NTM-PD) if they met ATS/IDSA guidelines for treatment or as nontuberculous mycobacteria-colonized (NTM-C) if they did not meet ATS/IDSA criteria for NTM treatment. Patients with a chest CT were included in the analysis and CT scans were assessed for features including bronchiectasis, nodules, and cavities. Bronchiectasis severity was calculated using the modified Reiff scoring system. Univariate analyses were conducted to compare patients with NTM-C and NTM-PD.

RESULTS

Eighty-four patients were included in the analysis and 27 were classified as NTM-C and 57 as NTM-PD. NTM-PD patients had a greater median number of lung lobes affected by bronchiectatic airways (6 [1] NTM-PD vs. 5 [3] NTM-C P=0.005) and a greater frequency of cystic bronchiectasis (17.5% NTM-PD vs. 0% NTM-PD, P=0.016). Bronchiectasis severity was higher for NTM-PD patients (7 [9] NTM-PD vs. 5 [1.5] NTM-C, P<0.001).

CONCLUSIONS

Patients with NTM-PD have greater bronchiectatic airway involvement and the forms of bronchiectasis present are more severe compared with NTM-C patients. In addition, cavitation of lung parenchyma was a radiographic feature solely associated with NTM-PD. Features identified on chest CT may be useful as a prognostic biomarker for the risk of transition from NTM-C to NTM-PD.

Differentiating nontuberculous mycobacterium pulmonary disease from pulmonary tuberculosis through the analysis of the cavity features in CT images using radiomics

OBJECTIVE

To differentiate nontuberculous mycobacteria (NTM) pulmonary diseases from pulmonary tuberculosis (PTB) by analyzing the CT radiomics features of their cavity.

METHODS

73 patients of NTM pulmonary diseases and 69 patients of PTB with the cavity in Shandong Province Chest Hospital and Qilu Hospital of Shandong University were retrospectively analyzed. 20 patients of NTM pulmonary diseases and 20 patients of PTB with the cavity in Jinan Infectious Disease Hospitall were collected for external validation of the model. 379 cavities as the region of interesting (ROI) from chest CT images were performed by 2 experienced radiologists. 80% of cavities were allocated to the training set and 20% to the validation set using a random number generated by a computer. 1409 radiomics features extracted from the Huiying Radcloud platform were used to analyze the two kinds of diseases' CT cavity characteristics. Feature selection was performed using analysis of variance (ANOVA) and least absolute shrinkage and selection operator (LASSO) methods, and six supervised learning classifiers (KNN, SVM, XGBoost, RF, LR, and DT models) were used to analyze the features.

RESULTS

29 optimal features were selected by the variance threshold method, K best method, and Lasso algorithm.and the ROC curve values are obtained. In the training set, the AUC values of the six models were all greater than 0.97, 95% CI were 0.95-1.00, the sensitivity was greater than 0.92, and the specificity was greater than 0.92. In the validation set, the AUC values of the six models were all greater than 0.84, 95% CI were 0.76-1.00, the sensitivity was greater than 0.79, and the specificity was greater than 0.79. In the external validation set, The AUC values of the six models were all greater than 0.84, LR classifier has the highest precision, recall and F1-score, which were 0.92, 0.94, 0.93.

CONCLUSION

The radiomics features extracted from cavity on CT images can provide effective proof in distinguishing the NTM pulmonary disease from PTB, and the radiomics analysis shows a more accurate diagnosis than the radiologists. Among the six classifiers, LR classifier has the best performance in identifying two diseases.

[Pulmonary Nontuberculous Mycobacteriosis Difficult to Differentiate from Local Recurrence of the Metastatic Lung Tumor of the Uterine Cervix Cancer at the Staple-line:Report of a Case]

A 70-year-old woman underwent right S6 segmentectomy and left S6 partial resection for lung metastasis of uterine cervix cancer. Although she received adjuvant chemotherapy, chest computed tomography revealed a new pulmonary nodule on the staple stump of the right lung. We diagnosed the tumor as local recurrence at the stump and planned to continue chemotherapy. However, the size of the tumor increased, and we performed right middle and lower lobectomy. Based on the pathological and bacteriological examinations, an epithelioid cell granuloma infected by Mycobacterium avium was established.

A New Model of Chronic Mycobacterium abscessus Lung Infection in Immunocompetent Mice

Pulmonary infections caused by Mycobacterium abscessus (MA) have increased over recent decades, affecting individuals with underlying pathologies such as chronic obstructive pulmonary disease, bronchiectasis and, especially, cystic fibrosis. The lack of a representative and standardized model of chronic infection in mice has limited steps forward in the field of MA pulmonary infection. To overcome this challenge, we refined the method of agar beads to establish MA chronic infection in immunocompetent mice. We evaluated bacterial count, lung pathology and markers of inflammation and we performed longitudinal studies with magnetic resonance imaging (MRI) up to three months after MA infection. In this model, MA was able to establish a persistent lung infection for up to two months and with minimal systemic spread. Lung histopathological analysis revealed granulomatous inflammation around bronchi characterized by the presence of lymphocytes, aggregates of vacuolated histiocytes and a few neutrophils, mimicking the damage observed in humans. Furthermore, MA lung lesions were successfully monitored for the first time by MRI. The availability of this murine model and the introduction of the successfully longitudinal monitoring of the murine lung lesions with MRI pave the way for further investigations on the impact of MA pathogenesis and the efficacy of novel treatments.

Nodular distribution pattern on chest computed tomography (CT) in patients diagnosed with nontuberculous mycobacteria (NTM) infections

BACKGROUND

This study evaluated the prevalence of spreading pathways in nontuberculous mycobacteria (NTM) pulmonary infections according to nodular distribution patterns seen on chest computed tomography (CT).

METHODS

This study included 63 patients diagnosed with NTM lung infections who underwent CT at our institution. A retrospective analysis of CT images focused on the presence and distribution of nodules, presence of intrathoracic lymphadenopathy and the predominant side of infection in the lungs. The findings were classified into five groups; centrilobular (bronchogenic spread), perilymphatic (lymphangitic spread), random (hematogenous spread), combined pattern and no nodules present. The groups were then compared according to other CT findings.

RESULTS

Among 51 (81%) patients identified with a nodular pattern on chest CT, 25 (39.8%) presented with centrilobular, 7 (11.1%) with perilymphatic, 6 (9.5%) with random and 13 (20.6%) with combined nodular patterns but located in different areas of the lungs. The right side of the lungs was predominant in 38 cases (60.3%). Intrathoracic lymphadenopathy was evident in 20 patients (31.7%). Significant differences in distributions of nodular patterns were seen in patients infected with Mycoplasma avium complex (MAC) associated with centrilobular pattern (p = 0.0019) and M. fortuitum associated with random pattern (p = 0.0004). Some of the findings were related to perilymphatic nodules between other isolated species of NTM (p = 0.0379).

CONCLUSION

The results of this study showed a high proportion of perilymphatic nodules and right-sided predominance in the upper lobe, which, combined with intrathoracic lymphadenopathy is highly suggestive of the lymphangitic spread of lung NTM infections.

Computed tomographic findings of macrolide-resistant Mycobacterium massiliense pulmonary disease and changes after antibiotic treatment

The purpose of this study was to present the computed tomographic (CT) findings of lung abnormalities in macrolide-resistant Mycobacterium massiliense pulmonary disease and its changes in follow-up CT after antibiotic treatment.Chest CT scans of patients with macrolide-resistant M massiliense pulmonary disease (n = 19) were retrospectively reviewed. Patients were treated with multidrug therapy, and sputum examinations were performed. Follow-up CT scans obtained during antibiotic treatment after detection of macrolide resistance were also reviewed, if available (n = 13). The CT scores at detection of macrolide resistance and at the last follow-up periods were also compared.Of all patients with macrolide-resistant M massiliense pulmonary disease, 2 (11%) patients achieved sputum culture conversion during the follow-up period. The most common CT findings of M massiliense pulmonary disease at detection of macrolide resistance were bronchiectasis and bronchiolitis (n = 19, 100%), followed by consolidation (n = 16, 84%), cavities (n = 11, 58%), and nodules (n = 6, 32%). On the last follow-up CT, overall CT scores were increased in 8 (62%) of 13 patients, and total mean CT score was significantly increased (P = .021). For each CT pattern, the cavity showed the greatest increase in CT score (P = .027), followed by bronchiectasis (P = .038).Common CT findings of macrolide-resistant M massiliense pulmonary disease were similar to those of pulmonary disease caused by other species of nontuberculous mycobacteria at presentation. However, in macrolide-resistant M massiliense pulmonary disease, serial CT scans showed deterioration with cavitary and bronchiectatic change in most patients despite multidrug antibiotic therapy.

Outcome of patients with and poor prognostic factors for Mycobacterium kansasii-pulmonary disease

BACKGROUND

Aggressive therapy for Mycobacterium kansasii-pulmonary disease (MK-PD) is recommended because of the virulence of MK. However, some clinicians may be concerned regarding the lengthy course and numerous adverse effects. This study evaluated the natural course of MK-PD and investigated its prognostic factors.

METHODS

Radiographic outcome, prognostic factors, and mortality within 1 year for MK-PD were obtained from patients in 6 hospitals in Taiwan from 2010 to 2014 (derivation cohort) and validated using patients in 2015 and 2016 (validation cohort).

RESULTS

Of the 109 patients with MK-PD in the derivation cohort, radiographic progression occurred in 70 (64%), with a 1-year mortality rate of 43% and median survival of 71 days, whereas none of the 39 cases without radiographic progression died. All patients with acid-fast smear (AFS) grade ≥ 3 experienced radiographic progression. For the others, the independent risk factors of radiographic progression were fibroCavitary pattern, Leucocyte count >9000/μL, Old age (age >65 years), pUre MK in sputum (no other mycobacteria), and no Diabetes mellitus (the CLOUD factors). By applying these criteria to the validation cohort (n = 112), 3 (9%) of the 33 patients with MK-PD who initially had AFS grade < 3 and < 3 CLOUD risk factors experienced radiographic progression, and none of the 3 died of MK-PD.

CONCLUSIONS

Because of the high risk of radiographic progression and subsequent fatal outcome, immediate anti-MK treatment is recommended. For patients with MK-PD who have sputum AFS grade <3 and < 3 CLOUD risk factors, regular follow-up may be an alternative.

Non-tuberculous mycobacterial pulmonary infections

BAKGRUNN

Lungeinfeksjoner med ikke-tuberkuløse mykobakterier påvises jevnlig i klinisk praksis. Diagnostikk og behandling er utfordrende, og internasjonale retningslinjer bygger i stor grad på erfaring og kasuistikker. Temaet er kort og generelt omtalt i Tuberkuloseveilederen, utover det finnes ingen nasjonal behandlingsveileder om temaet. Denne artikkelen sammenfatter den nyeste kunnskapen om emnet, med hovedvekt på diagnostikk og behandling.

KUNNSKAPSGRUNNLAG

Vi søkte i PubMed, Embase og Cochrane etter alle oversiktsartikler og systematiske oversiktsartikler i tidsrommet 2007-17 om ikke-tuberkuløse mykobakterier som årsak til lungesykdom.

RESULTATER

Ved diagnostikk og behandling av lungeinfeksjoner med ikke-tuberkuløse mykobakterier må både kliniske, radiologiske og mikrobiologiske funn vurderes før man beslutter om det er behandlingsindikasjon. Identifikasjon av art og eventuell underart av påvist mykobakterie og resistensmønster er av stor betydning. Behandlingen består av en kombinasjon av flere medikamenter over lang tid som ofte har mange bivirkninger og interaksjoner.

FORTOLKNING

Behandlingsresultatene for lungeinfeksjoner med ikke-tuberkuløse mykobakterier er varierende. Det er viktig å ta stilling til om nytten av behandlingen forventes å oppveie ulempene den kan medføre. For mange pasienter vil optimalisering av øvrig behandling for den underliggende lungesykdommen være viktigst. Pasientene må følges opp regelmessig med ekspektoratprøver og monitorering av bivirkninger.

[Pulmonary Nontuberculous Mycobacteriosis Appeared at the Surgical Margin of the Lung Cancer Surgery;Report of a Case]

A 70-year-old woman had undergone right S8+9 segmentectomy for stage I A lung cancer. Surgical staplers were used for an intersegmental line. Two years after surgery, routine chest computed tomography(CT) showed a 40-mm mass around the staple line in the right lower lobe, and positron emission tomography (PET) was positive. The mass was suspected to be local recurrence of lung cancer, and she was done additional surgery for resection of the remaining right lower lobe. The pathologic diagnosis was lung nontuberculous mycobacteriosis. It was suggested that nontuberculous mycobacteriosis developed at the atelectasis around the staple line. In addition to local recurrence, the possibility of nontuberculous mycobacteriosis should be considered in cases of pulmonary nodules appearing at the staple line after pulmonary resection.

Dissemination of localized Mycobacterium malmoense infection in an immunocompromised patient

A 75-year-old woman with a history of immunosuppressive treatment for rheumatoid arthritis and non-Hodgkin lymphoma, was referred to our reference centre for treatment of tenosynovitis caused by Mycobacterium malmoense, which had disseminated due to immunosuppressive therapy. This rare diagnosis was made after years of treatment for supposed rheumatoid arthritis. The patient presented with relapsing tenosynovitis with wounds on her right middle finger and wounds on her left lower leg, despite 3 months of adequate therapy (rifampicin+ethambutol+clarithromycin). Therapy was intensified with amikacin, clofazimine, moxifloxacin, and interferon-gamma due to the lack of response. Amputation of the right middle finger was necessary due to advanced disease. Treatment was further complicated by a paradoxical reaction, requiring prednisone treatment, which ultimately led to cure.

Influence of intersegmental plane size and segment division methods on preserved lung volume and function after pulmonary segmentectomy

OBJECTIVES

We previously reported that the use of a stapler to divide intersegmental planes did not decrease preserved pulmonary volume or function relative to electrocautery. However, preservation of pulmonary volume or function can be compromised when a stapler is used with larger intersegmental planes. Here, we assessed the correlations between preserved lung volume and pulmonary function after segmentectomy and the size of the intersegmental planes, based on the division method.

METHODS

Intersegmental plane sizes in 56 patients were semi-automatically calculated using image analysis software on computed tomography images. The ratios of the remnant segment and ipsilateral lung volumes to their preoperative values (R-seg and R-ips) and the ratio of the postoperative pulmonary function relative to the predicted value were calculated based on three-dimensional volumetry. Correlations between preserved lung volume and pulmonary function and the intersegmental plane sizes were analyzed according to the division method.

RESULTS

Intersegmental planes were divided by either electrocautery or with a stapler (EC/Mixed) in 21 patients and by stapler alone (ST) in 35 patients. There was no difference in the average size of the intersegmental planes between the two groups. The intersegmental plane size negatively correlated with R-seg in the ST group.

CONCLUSIONS

Using the stapler method, as the size of the intersegmental planes increased, the preserved remnant segmental volume decreased; however, relation between the plane size and preserved pulmonary function was unclear. These findings indicate that stapler use is acceptable even for large intersegmental planes.

Clinical, radiological and molecular features of Mycobacterium kansasii pulmonary disease

BACKGROUND

Studies concerning sociodemographic, clinical, and laboratory features of Mycobacterium kansasii pulmonary disease are few and based on small patient cohorts. The objective of the study was to evaluate characteristics of patients from whom M. kansasii respiratory isolates were recovered and to provide a detailed description of M. kansasii disease.

BASIC PROCEDURES

Retrospective review of electronic medical records of all patients for whom at least one positive M. kansasii culture was obtained at the Department of Internal Medicine, Pulmonology and Allergology of the Warsaw Medical University between the year 2000 and 2015. Patients were categorized as having mycobacterial disease or as isolation cases based on the American Thoracic Society and Infectious Diseases Society of America (ATS/IDSA) diagnostic criteria.

MAIN FINDINGS

The study comprised of 105 patients (63 females, 42 males, mean age 64.6 ± 17.8 years). Of these, 86 (81.9%) were diagnosed as having M. kansasii disease. The proportion of positive smear microscopy was significantly higher in patients with M. kansasii disease compared to M. kansasii isolation (P < 0.001). There were no statistically significant differences between M. kansasii disease and isolation cases in terms of clinical symptoms or comorbidities. Patients with M. kansasii disease presented most commonly (43/86, 50%) fibro-cavitary disease upon radiology. Lesion distribution usually showed bilateral upper lobe involvement. Among the 191 isolates genotyped, all were identified as M. kansasii type I.

PRINCIPAL CONCLUSIONS

The findings from this study support the relaxation of the diagnostic criteria for the definition of M. kansasii disease, set forth by ATS/IDSA. Molecular typing did not differentiate isolates from patients with true disease from those with isolation only; the role of bacterial virulence factors thus remains elusive.

Causative species of nontuberculous mycobacterial lung disease and comparative investigation on clinical features of Mycobacterium abscessus complex disease: A retrospective analysis for two major hospitals in a subtropical region of Japan

Nontuberculous mycobacteria (NTM) lung disease is increasing globally. Although the etiological epidemiology of NTM is different across regions, Mycobacterium avium complex (MAC) is the leading cause of NTM lung disease in most countries, including mainland Japan. Okinawa is located in the southernmost region of Japan and is the only prefecture categorized as a subtropical region in Japan, it is therefore likely the etiological epidemiology of NTM lung disease is different from mainland Japan. From 2009 to 2015, the medical records of patients, with respiratory specimens positive for NTMs, visiting or admitted to two Okinawan hospitals, were retrospectively analyzed. NTM lung disease cases were defined according to the American Thoracic Society criteria and patient epidemiology and clinical information were evaluated. Results indicate four hundred sixteen patients had bacterial cultures positive for NTM. The most common NTM was M. abscessus complex (MABC) (n = 127; 30.5%), followed by M. intracellulare (n = 85; 20.4%). NTM lung disease was diagnosed in 114 patients. Of these cases, MABC was most common (n = 41; 36.0%), followed by M. intracellulare (n = 31; 27.2%). Chronic obstructive pulmonary disease (COPD) and tracheostomy patients were more likely to develop MABC than MAC lung disease. Multivariate analysis showed a probable association between COPD and MABC lung disease. Chest computed tomography (CT) evaluation revealed bronchiectasis, nodules, and consolidation were less frequently observed in MABC patients compared with MAC patients. Our data suggests Okinawa may be one of the few places where MABC is the predominant pathogen causing NTM lung disease and our results add new insight to MABC lung disease, which is not yet well understood.

Body habitus in patients with and without bronchiectasis and non-tuberculous mycobacteria

Background

Female gender, tall stature, presence of bronchiectasis are associated with pulmonary nontuberculous mycobacterial (NTM) infections. The biologic relationship between the body habitus and NTM infection is not well defined and the body habitus profile of the patients with NTM and concurrent bronchiectasis is completely unknown.

Methods

We conducted a case control study at the Miami VA Healthcare System and the University of Illinois Medical Center on patients with pulmonary NTM infections between 2010 and 2015. We compared pulmonary NTM subjects with and without bronchiectasis. NTM infection was confirmed by using the American Thoracic Society/ Infectious Disease Society of America criteria. Standard radiological criteria were used to define bronchiectasis in chest CT-scan.

Results

Two hundred twenty subjects with pulmonary NTM were enrolled in the study. Sixty six subjects (30%) had bronchiectasis on CT scan of the chest. Subjects in the bronchiectasis group included more women (p = 0.002) and were significantly older (p = 0.005). Those patients who had bronchiectasis tended to have a significantly lower weight (less than 50kg) and height ≤155 cm (p <0.0001 and p = 0.018, respectively). Kaplan–Meier analysis confirmed that subjects who had bronchiectasis were shorter and weighed less, after adjusting for gender.

Conclusions

This study defines a new sub-phenotype of NTM subjects with bronchiectasis who tend to be short with lower body weight. Further studies are needed to better understand and define the body habitus profiles of this new sub-phenotype and their clinical implications.

Prosthetic Valve Infective Endocarditis With Mycobacterium Fortuitum: Antibiotics Alone Can Be Curative

Rapidly growing non-tuberculous mycobacteria (RGM) are a rare, often fatal cause of infective endocarditis. Although surgery has been the cornerstone of RGM endocarditis therapy, we present the first documented adult case of Mycobacterium fortuitum endocarditis cured with antibiotic therapy.

Comparison of chest CT findings in nontuberculous mycobacterial diseases vs. Mycobacterium tuberculosis lung disease in HIV-negative patients with cavities

Objectives

This article focuses on the differences between CT findings of HIV-negative patients who have cavities with nontuberculous mycobacteria (NTM) disease and those with Mycobacterium tuberculosis infections (TB).

Methods

We retrospectively reviewed 128 NTM disease patients (79 males and 49 females) with cavities in chest CT, matched for age and gender with 128 TB patients in the same period. Sputum cultures of all patients were positive for pathogens. Two independent chest radiologists evaluated the characteristics of the largest cavity and related factors.

Results

Interobserver agreement was excellent (κ value, 0.853–0.938). Cavity walls in NTM disease were significantly thinner (6.9±4 mm vs 10.9±6 mm, P<0.001) and more even (the ratio of thickness, 2.6±1 vs 3.7±2, P<0.001) than those in TB. The thickening of adjacent pleura next to the cavity was also significantly thicker in NTM than TB (P<0.001). However, in the multivariate analysis, thickening of adjacent pleura was the only significant factor among the representative cavity findings (Odds ratio [OR], 6.49; P<0.001). In addition, ill-defined tree-in-bud nodules (OR, 8.82; P<0.001), number of non-cavitary nodules (≥10mm) (OR, 0.72; P = 0.003), and bronchiectasis in the RUL (OR, 5.3; P = 0.002) were significantly associated ancillary findings with NTM disease in the multivariate analysis.

Conclusions

The major cavities in NTM disease generally have thinner and more even walls than those in TB. When cavities are associated with adjacent pleural thickening, ill-defined satellite tree-in-bud nodules, or fewer non-cavitary nodules ≥10 mm, these CT findings are highly suggestive of NTM disease rather than TB.

Factors which influence treatment initiation for pulmonary non-tuberculous mycobacterium infection in HIV negative patients; a multicentre observational study

BACKGROUND

Clinical, radiological and microbiological criteria inform diagnosis of pulmonary Non-Tuberculous Mycobacteria (NTM) disease and treatment decisions. This multicentre, review aims to characterise NTM disease meeting ATS/IDSA criteria and define factors associated with initiation of treatment.

METHODS

Sputum samples growing NTM from 5 London hospitals between 2010 and 2014 were identified. Data for HIV-negative individuals meeting ATS/IDSA guidelines for pulmonary NTM disease were extracted. Associations between clinical variables and treatment decision were investigated using Chi-squared, Fishers-exact or Mann Whitney tests. Factors associated with treatment in univariate analysis (p < 0.150) were included in a multivariate logistic regression model.

RESULTS

NTM were identified from 817 individuals' sputum samples. 108 met ATS/IDSA criteria. 42/108 (39%) were initiated on treatment. Median age was 68 (56-78) in the cohort. On multivariate analysis, factors significantly associated with treatment of pulmonary NTM infection were: Cavitation on HRCT (OR: 6.49; 95% CI: 2.36-17.81), presenting with night sweats (OR 4.18; 95% CI: 1.08-16.13), and presenting with weight loss (OR 3.02; 95% CI: 1.15-7.93). Of those treated, 18(43%) have completed treatment, 9(21%) remain on treatment, 10(24%) stopped due to side effects, 5(12%) died during treatment. Mortality was 31% (n = 13) in treated versus 21% (n = 14) in the non-treated cohort. Subgroup analysis of individual NTM species did not observe any differences in treatment initiation or outcomes between groups.

DISCUSSION

Decision to treat pulmonary NTM infection requires clinical judgement when interpreting clinical guidelines. Factors independently associated with decision to treat in this HIV-negative cohort include cavitation on HRCT and presenting with night sweats or weight loss.

[Pulmonary granulomatous diseases and pulmonary manifestations of systemic granulomatous disease : Including tuberculosis and nontuberculous mycobacteriosis]

CLINICAL/METHODICAL ISSUE

Granulomas as signs of specific inflammation of the lungs are found in various diseases with pulmonary manifestations and represent an important imaging finding.

STANDARD RADIOLOGICAL METHODS

The standard imaging modality for the work-up of granulomatous diseases of the lungs is most often thin-slice computed tomography (CT). There are a few instances, e. g. tuberculosis, sarcoidosis and silicosis, where a chest radiograph still plays an important role.

METHODICAL INNOVATIONS

Further radiological modalities are usually not needed in the routine work-up of granulomatous diseases of the chest. In special cases magnetic resonance imaging (MRI) and positron emission tomography (PET)-CT scans play an important role, e. g. detecting cardiac sarcoidosis by cardiac MRI or choline C‑11 PET-CT in diagnosing lung carcinoma in scar tissue after tuberculosis.

PERFORMANCE

The accuracy of thin-slice CT is very high for granulomatous diseases.

ACHIEVEMENTS

In cases of chronic disease and fibrotic interstitial lung disease it is important to perform thin-slice CT in order to diagnose a specific disease pattern. Thin-slice CT is also highly sensitive in detecting disease complications and comorbidities, such as malignancies. Given these indications thin-slice CT is generally accepted in the routine daily practice.

PRACTICAL RECOMMENDATIONS

A thin-slice CT and an interdisciplinary discussion are recommended in many cases with a suspected diagnosis of pulmonary granulomatous disease due to clinical or radiographic findings.

[SURGICAL TREATMENT FOR TWENTIES PATIENTS WITH PULMONARY NONTUBERCULOUS MYCOBACTERIOSIS RESISTING CHEMOTHERAPY]

SUBJECTS AND METHODS

We report five cases of surgical treatment for pulmonary nontuberculous mycobac- teriosis (NTM) resisting chemotherapy in twenties. Of the five, one was male and four were female. They had cavitary or nodular lesion in their lung. After chemotherapy, partial resection or lobectomy was performed.

RESULT

Though postoperative chemotherapy had contin- ued for only 6 months or 1 year, there was no relapse/recurrence at more than 86 months in average after surgery. Consideration. In younger patients, NTM lesions in the lung are sometimes more localized than senior patients, therefore they can be removed as a smaller portion by the operation, and we can sometimes keep more pulmonary function of the patient.

CONCLUSION

Surgical treatment for twenties patients with pulmonary nontuberculous mycobacteriosis resisting chemo- therapy should be carried out aggressively at an early stage to resect a smaller portion of the lung and also decrease relapse/ recurrence after surgery.

Rapid Diagnosis of Mycobacterium genavense Disseminated Infection by the Microseq 500: A Case Report in A Two Year Old HIV-Negative Child

This paper evaluates the capability of MicroSeq 500 instrument to improve the diagnosis of Mycobacterium genavense The strain was isolated from a two year old child admitted to our hospital for hepatosplenomegaly and massive abdominal lymphadenopathies. DNA was extracted from a lymph node and examined by amplifying 500 bp at the 5' end of 16S rRNA gene using MicroSeq 500 16S rDNA Bacterial Identification PCR kit. Sequencing reactions were performed with MicroSeq 500 16S rDNA Bacterial Identification Sequencing kit (Applied Biosystems, USA). Afterwards, sequences were analyzed by GenBank database and identified as Mycobacterium genavense, a slow-growing nontuberculous mycobacterium. The use of 16S rRNA gene sequencing for the identification of bacteria allows the recognition of new clinically relevant agents, eliminating the culture result waiting times.

[Pulmonary infections with non-tuberculous mycobacteria]

In recent decades, an increasing incidence of pulmonary infections with non-tuberculous mycobacteria has been reported, primarily affecting patients with structural lung diseases and/or immunosuppression. In Denmark, approximately 100 new cases of infection with non-tuberculous mycobacteria occur yearly, most commonly with Mycobac-terium avium complex. Diagnosis is based on clinical, radiological and microbiological criteria. Treatment is difficult, and outcomes are often poor. Antibiotic treatment should be performed by specialists with reference to international guidelines.

[MYCOBACTERIUM ABSCESSUS PULMONARY DISEASE: IMPORTANT PATHOGEN INVOLVED IN MICROBIAL SUBSTITUTION DURING THE TREATMENT OF NON-ABSCESSUS MYCOBACTERIAL DISEASE]

INTRODUCTION

Mycobacterium abscessus pulmonary disease is common in patients with bronchiectasis. However, the underlying disease that is more likely to be present in patients with M. abscessus pulmonary disease remains poorly understood.

METHOD

From 2001 through 2010, all patients, whose sputum or bronchoscopic lavage cultures yielded M. abscessus, were included in the study.

RESULTS

Among the 11 patients included (male/female: 4/7), 4 male patients had a history of smoking. All 11 patients presented with bronchiectasis on computed tomography before the detection of M. abscessus, and most patients demonstrated nodular bronchiectasis on chest computed tomography. Six patients (54.5%) developed M. abscessus pulmonary disease during treatment for non-abscessus non-tuberculous mycobacterial disease: M. avium complex pulmonary disease in 5 and M. kansasii infection in 1. Although laboratory examination yielded negative findings for non-abscessus mycobacterium when M. abscessus was detected, radiographic deterioration was observed in 4 of 6 patients. Five patients received drug therapy, 3 of whom were treated with multi-drug therapy including clarithromycin, ethambutol, and rifampicin, and the remaining 2 patients received low-dose macrolide therapy. However, M. abscessus was detected consistently in all patients, and deteriorated chest CT findings were observed in 4. Among the remaining 6 patients untreated with drugs, sputum cultures yielded. M. abscessus with radiographic deterioration in 4 patients.

CONCLUSION

Our results indicated that M. abscessus infection developed during the treatment for non-abscessus mycobacterial disease, which was mainly due to M. avium complex pulmonary disease in most patients. M. abscessus infection thus occurred via microbial substitution. This phenomenon should be considered an important issue during the treatment for non-abscessus mycobacterial disease, which requires long-term medication.

[Mycobacterium kansasii lung infection]

The incidence of non tuberculosis mycobacterial (NTM) pulmonary diseases is increasing. Patients with NTM disease usually suffer prolonged periods of clinical illness prior to diagnosis. An etiological treatment, initiated by a well informed clinician and based on presumptive evidence, can be successful in a significant proportion of cases.

Newly detected pulmonary nontuberculous mycobacterial infection and peripheral lung cancers in patients during follow-up of idiopathic interstitial pneumonia: comparison of CT findings

This article describes the difference between the computed tomography (CT) findings in patients with newly detected pulmonary nontuberculous mycobacterial infection (NTM-IIP) and Cancer-IIP. We retrospectively evaluated 35 NTM-IIP and 78 Cancer-IIP patients in reference to their null idiopathic interstitial pneumonia CT (n = 113), using >10 years of data. Two independent radiologists analyzed the CT characteristics and the axial location of the main opacity. The interobserver agreement was good (κ > 0.771). The NTM-IIP patients were older (P = 0.034). The median size of the main opacity in the NTM-IIP (27 mm; 11-73) was larger (19 mm; 5-60; P = 0.002). Consolidation (n = 30; 85.7%; odds ratio [OR], 45) and cavities (n = 14; 40%, OR, 25) were more common in NTM-IIP (all P < 0.001). The midst of the fibrotic cysts including honeycomb cysts (n = 16; 45.7%, OR, 4.95) was more common in NTM-IIP (P = 0.006). NTM-IIP appeared larger, with more frequent consolidation and cavities, and was more likely to have been located in the midst of the fibrotic cysts including honeycomb cysts at the CT, which showed that it was older than Cancer-IIP.

Risk factors for mortality in patients with pulmonary infections with non-tuberculous mycobacteria: a retrospective cohort study

BACKGROUND

Infections with non-tuberculous mycobacteria (NTM) represent an increasing problem. Their clinical relevance is still largely unknown as well as predictors for mortality in affected patients. The objective was to describe prevalence and clinical relevance of different NTM and to identify risk factors for mortality.

METHODS

Retrospective cohort study of 124 patients with NTM detection between January 2001 and December 2011. Clinical characteristics like symptoms and radiological appearance were assessed at presentation. The primary outcome was all cause mortality during the follow-up period. Univariate and multivariate survival analyses using Cox proportional hazard models were employed for statistical analysis.

RESULTS

Over the study period, the frequency of NTM isolation varied from 4 to 12 patients per year. Twenty-nine out of 124 patients (23%) had a clinically relevant infection, according to the criteria of the American Thoracic Society (ATS). Mycobacterium avium was isolated most frequently, but Mycobacterium kansasii, Mycobacterium malmoense and Mycobacterium xenopi had the highest clinical relevance. Symptoms were mostly diverse and non-specific. On radiology, cavities were observed more frequently than a nodular-bronchiectatic variant or consolidation. In 75% of all patients, follow up time was more than two years. Median survival was 6.5 years (95%CI = 2.7-10.3). Factors significantly influencing survival time were haemoptysis (HR = 0.2, 95%CI = 0.1-0.6) and a consolidation on imaging (HR = 5.1, 95%CI 1.4-18.2).

CONCLUSIONS

The presentation of an infection with NTM can be diverse and depends mainly on the causative NTM pathogen. The most important predictor for increased mortality is the radiological appearance of a consolidation.

A Case of Systemic Osteomyelitides Due toMycobacterium avium

A case of multiple osteomyelitides due to Mycobacterium avium (M. avium) infection with osteosclerotic bone lesions is reported. A 67-year-old male had been suffering from persistent fever and back pain since October 1999, and 20.0-2.5 mg prednisolone per day was prescribed for continuous inflammatory symptoms in January 2000. Six months later, computed tomography revealed osteosclerotic lesions in the left femur and thoracic vertebrae, but no skin lesion associated with mastocytosis or internal malignancy was identified. In September of 2002, a dome-shaped, soft subcutaneous tumor developed on the upper sternum. Histopathological findings revealed subcutaneous adipose tissue with several foci of tiny abscesses. Two weeks later, creamy pus was discharged through a draining sinus at the center of the wound. M. avium was demonstrated in the pus by Zeel-Nielsen staining and microplate hybridization.

Nontuberculous mycobacterial infection after therapy with temsirolimus for metastatic renal cell carcinoma

We describe the case of a patient with metastatic renal cell carcinoma (mRCC) who developed a nontuberculous mycobacteria (NTM)-related pulmonary nodule during therapy with the mammalian target of rapamycin (mTOR) inhibitor temsirolimus. After discontinuation of temsirolimus treatment, a small pulmonary nodule with increased glucose uptake was detected on a positron emission tomography (PET) scan. A lung resection carried out to confirm and treat the suspected solitary metastasis of RCC yielded the surprising finding of a caseating granuloma containing NTM. A single PET-positive nodule presents a significant differential diagnostic dilemma in the setting of mRCC treated with mTOR inhibitors. Although the treatment of mRCC with temsirolimus can lead to immunosuppression and opportunistic infections, there is no report to our knowledge on the occurrence of NTM infections in mRCC patients treated with mTOR inhibitors. These infections should be included in the differential diagnosis of lung nodules. Interestingly, there is strong preclinical evidence pointing to direct and indirect antimycobacterial activity of mTOR inhibitors. We therefore hypothesize that while the seeding of NTM can occur during temsirolimus therapy due to T-lymphocyte suppression, the infection may only become active after the discontinuation of mTOR inhibitor treatment.

[A comparison of chest radiographs between patients with pulmonary Mycobacterium kansasii infection and those with Mycobacterium tuberculosis infection in the initial stage of disease]

OBJECTIVES

To elucidate the differences in affected lung segments between patients with pulmonary M. kansasii infection and those with M. tuberculosis infection in the initial stage of disease, we examined chest radiography images and CT scans. The initial stage of disease was defined as the period when less than one-sixth of the total lung area was affected by the infection, as visualized on chest radiography and CT.

SUBJECTS AND METHODS

One hundred eighty-four patients were diagnosed with M.kansasii infection between 1996 and 2010 and 835 patients, with M.tuberculosis infection between 2008 and 2009 at our hospital. The diagnosis was made on the basis of the results of sputum culture and/or bronchial washing. After excluding the patients with underlying lung diseases such as chronic pulmonary emphysema, interstitial pneumonia, and old pulmonary tuberculosis as well as those in advanced stages, 24 patients with M. kansasii infection and 62 patients with M. tuberculosis infection were included in this study. The affected segments of the lungs and the rates of cavity development were determined by using CT scans.

RESULTS

In patients with M.kansasii, 17 had an infected right lung, while 7 had an infected left lung. Additionally, in patients with M.tuberculosis, 58 had an infected right lung, 3 had an infected left lung, and 1 had a bilateral infection. In patients infected with M. kansasii, the upper lobes were affected in 22 cases and the lower lobes in 3 cases. In patients infected with M. tuberculosis, the upper, middle, and lower lobes and the lingular segment were affected in 41, 8, 24, and 1 cases, respectively. Upper lobe lesions were seen more frequently in patients with M. kansasii infection than in those with M. tuberculosis infection (p < 0.05). Cavity formation was identified more frequently in patients infected with M. kansasii (91.7%) than in those infected with M. tuberculosis (32.3%) (p < 0.001). Cavitary lesions were more frequently localized to the apical, posterior, and apico-posterior regions (S1, S2 or S1 +2) of the upper lobes in patients infected with M. kansasii (86.4%) than in those infected with M. tuberculosis (35%) (p < 0.001). A solitary lesion without endobronchial spread, which is characterized by centrilobular micronodules and tree-in-bud appearance, was more frequently demonstrated in patients infected with M.ka nsasii (45.8%) than in those infected with M. tuberculosis (6.5%) (p < 0.001).

CONCLUSION

Our study revealed that the apical, posterior, and apico-posterior regions of the upper lobes are vulnerable to infection by not only M.tu berculosis, but also M.ka nsasii. It is likely that M.ka nsasii might gain access to these regions via the airways and that its weak virulence may lead to higher localization.

Multidrug resistant tuberculosis versus non-tuberculous mycobacterial infections: a CT-scan challenge

Introduction

Clinical, laboratory and imaging findings in patients with multidrug resistant-tuberculosis (MDR-TB) and non-tuberculosis mycobacterium (NTM) are similar, and the majority of these patients present with positive smear for Acid Fast Bacilli (ADB) and no response to first line anti-TB treatment, so sputum culture and PCR are necessary, especially in NTM.

Objective

In this study we evaluate more details of imaging findings to help earlier diagnosis of pathogens.

Materials and methods

66 patients with positive smear for AFB and no response to first line anti-TB drugs were divided into two groups by PCR and culture: MDR-TB (43 patients) and NTM (23 patients). Age, sex, history of anti-TB treatment, smoking and CT-scan findings (parenchymal, pleural and mediastinal variables) by details and lobar distribution were analyzed.

Results

Mean age of NTM patients was slightly higher (52 versus 45) and there is no significant difference in sex and smoking. In MDR-TB group, history of anti-TB treatment and evidence of chronic pulmonary disease such as calcified and fibrodestructed parenchyma, volume loss and pleural thickening were higher significantly. Cavities in MDR-TB were thick-wall in the background of consolidation, while NTM cavities were more thin-walled with adjacent satellite nodules in same segment or lobe. Prevalence of bronchiectasis was similar in both groups, while bronchiectasis in MDR-TB group was in fibrobronchiectatic background in upper lobes, and in NTM group the distribution was more uniform with slightly middle lobes predominance. Prevalence and distribution of nodular infiltrations were similar more in Tree in Buds and scattered pattern. Calcified or non-calcified lymph nodes and also pleural changes were more frequent in MDR-TB but prevalence of lymphadenopathy was mildly higher in NTM.

Conclusion

A check-list with multiple variables is helpful for differentiation between the two groups.

Radiological features and therapeutic responses of pulmonary nontuberculous mycobacterial disease in rheumatoid arthritis patients receiving biological agents: a retrospective multicenter study in Japan

Objective

This study was performed to evaluate the radiological features of and therapeutic responses to pulmonary disease caused by nontuberculous mycobacteria (NTM) in the setting of biological therapy for rheumatoid arthritis (RA).

Methods

We conducted a retrospective chart review of 13 patients from multiple centers who had developed pulmonary NTM disease during biological therapy for RA, including infliximab, etanercept, adalimumab, and tocilizumab.

Results

Most cases were asymptomatic or resulted in only common-cold-like symptoms. Abnormalities in computed tomography (CT) imaging were protean and frequently overlapped. The most predominant pattern was nodular/bronchiectatic disease (six cases), followed by alveolar infiltrate (three cases), cavitary disease (two cases), and pulmonary nodules (two cases). In most cases, pulmonary NTM disease had spread from a preexisting lesion; in particular, bronchial/bronchiolar abnormalities. In three cases, one or more nodular lesions with or without calcification were a focus of disease. Following the discontinuation of biological agents, most patients responded to anti-NTM therapy. Two patients showed no exacerbation in the absence of any anti-NTM therapy. In one patient, restarting tocilizumab therapy while continuing to receive adequate anti-NTM therapy produced a favorable outcome. In two other patients with a previous history of pulmonary NTM disease, introducing biological therapy led to recurrence, but anti-NTM therapy was effective in these patients.

Conclusion

CT abnormalities of pulmonary NTM disease in RA patients receiving biological therapy were variable, but were not unique to this clinical setting. NTM disease can spread from preexisting structural abnormalities, even if they are minute. Contrary to our expectations, the therapeutic outcomes of pulmonary NTM disease were favorable in these patients.

[Three cases of Mycobacterium kansasii pulmonary diseases in previously healthy young women]

Mycobacterium kansasii pulmonary diseases account for 20% of cases of non-tuberculous mycobacteria. Most patients are male. However, a recent study has found that radiological examinations in female patients often reveal nodular, bronchiectatic opacities. We describe 3 young women with cavitary opacities. Patient 1 was a 35-year-old woman in whom thin-walled cavitary opacities were detected in the upper lobe during a routine checkup. Sputum examination and fiberoptic bronchoscopy led to a diagnosis of M. kansasii pulmonary disease. Patient 2 was a 23-year-old woman who presented with hemoptysis. Thin-walled cavitary opacities were detected in the right upper lobe. Infection with M. kansasii was diagnosed after a sputum examination. Patient 3 was a 43-year-old woman in whom thin-walled cavitary opacities were detected in the left upper lobe during a routine checkup. Infection with M. kansasii was diagnosed after a fiberoptic bronchoscopic examination. Patient 1 was successfully treated with rifampicin, ethambutol, and levofloxacin, and patients 2 and 3 were successfully treated with isoniazid, rifampicin, and ethambutol. The possibility of M. kansasii pulmonary diseases should be considered in a previously healthy young woman with thin-walled cavitary opacities in the upper lobe.

Mycobacterium simiae infection in an immunocompetent patient, with DNA analyses verification

Mycobacterium simiae is a non-tuberculosis mycobacterium that does commonly cause clinical disease in immunocompromised patients with or without AIDS. We describe a case of M. simiae pulmonary infection in a patient without immunodeficiency syndrome, who had a history of Mycobacterium tuberculosis infections.

[Radiographic findings of pulmonary nontuberculous mycobacteriosis other than Mycobacterium avium complex]

Almost all nontuberculous mycobacteria (NTM) cause opportunistic infection. Therefore, the radiographic findings of NTM have a tendency of nonspecific patterns modifying the predisposing conditions or diseases and we could not extract species specific radiographic characterizations in that situations. In this review, the NTM cases without predisposing conditions or diseases are submitted essentially. Mycobacterium kansasii cases show more or less the same patterns with TB cases. Mycobacterium fortuitum case shows nonspecific consolidations. Mycobacterium xenopi case shows solitary cavity in the upper lobe area. Mycobacterium gordonae case shows the same cavitary pattern. Mycobacterium abscessus case shows widely scattered tree-in-bud appearance foci. Weak virulence NTM like as Mycobacterium xenopi or Mycobacterium gordonae may form solitary cavity without predisposing conditions. The pattern of bronchial wall thickening seems to be one of the specific findings with NTM pulmonary infection.

Lady Windermere syndrome: an inappropriate eponym for an increasingly important condition

Non-tuberculous mycobacterial infection (NMI) occurs in elderly women with no pre-existing lung disease, and this has been termed the Lady Windermere syndrome. NMIs are increasing in prevalence and an increasing number of pulmonary mycobacterial infections is due to non-tuberculous mycobacteria. The diagnosis is often difficult because the organism is not readily isolated or cultured, and the condition may not be considered by the radiologist. We report NMI in a 64-year-old woman, based on clinical and radiological findings. Although termed the Lady Windermere syndrome, the name does not correspond to the character in Oscar Wilde's play; hence the eponym is not widely used.

[A study on clinical features of Mycobacterium kansasii pulmonary disease in women]

OBJECTIVES

To clarify clinical features of M. kansasii pulmonary disease in women.

METHODS

We performed a retrospective analysis of M. kansasii pulmonary disease in women compairing with that in men. We focused on 8 female cases of M. kansasii pulmonary disease during the past 7 years from June 1998 to August 2005.

RESULTS

The cases of M. kansasii pulmonary disease in women have increased in the latter few years. The mean age of female cases was higher than that of male cases, 65.6 and 53.1 years old, respectively. The number of female cases with smoking history was lower than that of male cases, 37.5% and 90.0%, respectively. Two female cases had underlying pulmonary diseases, as compared with 10 male cases, 25.0% and 33.3%, respectively. The radiological findings in female cases included 2 cavitary opacities, 1 infiltrative opacity and 5 nodular, bronchiectatic opacities, as compared with 27 cavitary opacities, 1 infiltrative opacity, 1 solitary nodular opacity and 1 nodular, bronchiectatic opacity in male cases. MAC was also detected in 2 female cases, who presented with nodular, bronchiectatic opacities. On the other hand, there were 6 female cases, in which no other NTM was detected. 3 cases showed cavitary or infiltrative opacities, which improved with the following 3 tuberculous drugs INH, RFP, and EB (HRE), while others showed nodular, bronchiectatic opacities, in which 2 cases showed radiological exacerbations without any treatment and another one revealed an improvement with HRE.

CONCLUSIONS

M. kansasii pulmonary disease in women tends to be identified in elderly who smoke less and have no underlying pulmonary diseases, and most of radiological findings in female cases revealed nodular, bronchiectatic opacities. Summing up all these findings, clinical features of M. kansasii pulmonary disease in women was considered to resemble that of MAC infection, and it was speculated that the increase of M. kansasii pulmonary disease in women has some relationship with that of MAC infection in middle or lingular lobe. However, it was confirmed that some cases of M. kansasii pulmonary disease in women might primarily present with nodular, bronchiectatic lesions, regardless of MAC infection.

Differentiation of Mycobacterium kansasii infection from Mycobacterium tuberculosis infection: comparison of clinical features, radiological appearance, and outcome

This retrospective study sought to systematically identify clinical and radiological features differentiating Mycobacterium kansasii from Mycobacterium tuberculosis infection. The sample included matched patients with a culture-positive diagnosis of M. tuberculosis infection (n = 121) or M. kansasii infection (n = 62) derived from the databases of two tuberculosis centers. Data on patient background and clinical features were collected, and chest radiographs were analyzed. Sixty percent of the M. kansasii group were native Israelis compared to 15% of the M. tuberculosis group (p = 0.0001). M. tuberculosis infection was associated with a higher rate of human immunodeficiency virus (HIV) infection (p = 0.03) and M. kansasii infection with a higher rate of lung disease (p = 0.0001). M. tuberculosis infection was characterized by a higher likelihood of bilateral disease (p = 0.005), pleural effusions, and lymphadenopathy (p = 0.006 and p = 0.001, respectively). There were ten deaths, all in the M. tuberculosis group. On multivariate logistic regression, the presence of chronic obstructive pulmonary disease and associated lung disease were significant predictors of M. kansasii infection. The findings show that there are group differences between the clinical features of the two infections. In the setting of pulmonary mycobacterial infection, the presence of coinfection with HIV, bilateral disease, pleural effusion, and lymphadenopathy make M. kansasii infection very unlikely.

Pulmonary disease caused by Mycobacterium xenopi: the first case in Korea

Mycobacterium xenopi is a nontuberculous mycobacterium (NTM) that rarely causes pulmonary disease in Asia. Here we describe the first case of M. xenopi pulmonary disease in Korea. A 66-year-old man was admitted to our hospital with a 2-month history of productive cough and hemoptysis. His past medical history included pulmonary tuberculosis 44 years earlier, leading to a right upper lobectomy. Chest X-ray upon admission revealed cavitary consolidation involving the entire right lung. Numerous acid-fast bacilli were seen in his initial sputum, and M. xenopi was subsequently identified in more than five sputum cultures, using molecular methods. Despite treatment with clarithromycin, rifampicin, ethambutol, and streptomycin, the infiltrative shadow revealed on chest X-ray increased in size. The patient's condition worsened, and a right completion pneumonectomy was performed. The patient consequently died of respiratory failure on postoperative day 47, secondary to the development of a late bronchopleural fistula. This case serves as a reminder to clinicians that the incidence of NTM infection is increasing in Korea and that unusual NTM are capable of causing disease in non-immunocompromised patients.