Nontuberculous mycobacteria in diffuse panbronchiolitis

[Clinical analysis of 6 cases of diffuse panbronchiolitis in children]

OBJECTIVES

To analyze the clinical characteristics of diffuse panbronchiolitis (DPB) in children and to enhance the clinical diagnosis and treatment of this disease.

METHODS

A retrospective analysis was conducted on the clinical data of 6 children diagnosed with DPB who were hospitalized at The First Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2019.

RESULTS

Among the 6 patients, there were 2 males and 4 females; the age at diagnosis ranged from 7 to 12 years. All patients presented with cough, sputum production, and exertional dyspnea, and all had a history of sinusitis. Two cases showed positive serum cold agglutinin tests, and 5 cases exhibited pathological changes consistent with chronic bronchiolitis. High-resolution chest CT in all patients revealed centrilobular nodules diffusely distributed throughout both lungs with a tree-in-bud appearance. Five patients received low-dose azithromycin maintenance therapy, but 3 showed inadequate treatment response. After empirical anti-tuberculosis treatment, non-tuberculous Mycobacteria were found in the bronchoalveolar lavage fluid. Follow-up over 2 years showed 1 case cured, 3 cases significantly improved, and 2 cases partially improved.

CONCLUSIONS

The clinical presentation of DPB is non-specific and can easily lead to misdiagnosis. In cases where DPB is clinically diagnosed but does not show improvement with low-dose azithromycin treatment, special infections should be considered.

Pathophysiology of pulmonary nontuberculous mycobacterial (NTM) disease

In recent years, the incidence and prevalence of pulmonary nontuberculous mycobacterial (NTM) disease have increased worldwide. Although the reasons for this increase are unclear, dealing with this disease is essential. Pulmonary NTM disease is a chronic pulmonary infection caused by NTM bacteria, which are ubiquitous in various environments. In Japan, Mycobacterium avium-intracellulare complex (MAC) accounts for approximately 90% of the causative organisms of pulmonary NTM disease, which is also called pulmonary MAC disease or pulmonary MAI disease. It is important to elucidate the pathophysiology of this disease, which occurs frequently in postmenopausal women despite the absence of obvious immunodeficiency. The pathophysiology of this disease has not been fully elucidated; however, it can largely be divided into bacterial (environmental) and host-side problems. The host factors can be further divided into immune and airway problems. The authors suggest that the triangular relationship between bacteria, immunity, and the airway is important in the pathophysiology of this disease. The latest findings on the pathophysiology of pulmonary NTM disease are reviewed.

Comorbidities of nontuberculous mycobacteria infection in Korean adults: results from the National Health Insurance Service–National Sample Cohort (NHIS–NSC) database

Background

The global prevalence and incidence of nontuberculous mycobacteria (NTM) infection are increasing. However, the prevalence of NTM infection-associated comorbidities remains understudied. Thus, we investigated the comorbidities associated with NTM infection using the National Health Insurance Service-National Sample Cohort (NHIS–NSC) 2.0 database of the National Health Insurance Service (NHIS).

Methods

In this case–control study, patients with NTM infection and controls aged 20–89 years of age were matched 1:4 by sex, age, region, and income. A total of 26 comorbidities were selected based on previous reports and claims data analysis. The distribution of comorbidities was compared between patients with NTM infection and controls by sex and age using logistic regression analysis.

Results

In total, 893 patients (379 men and 514 women) with NTM infection (mean age, 56.1 years) and 3,572 controls (mean age, 55.6 years) were included. The odds ratio for prevalence of respiratory diseases, metabolic diseases, musculoskeletal disorders, gastrointestinal diseases, skin diseases, mental diseases, and neoplasms was significantly higher in patients with NTM infection than in the control group. Among comorbid diseases, the odds ratios (ORs) for the prevalence of the respiratory diseases such as bronchiectasis (OR [95% confidence interval (CI)]: 26.79 [19.69–36.45]) and interstitial pneumonitis (OR [95% CI]: 15.10 [7.15–31.89]) were the highest. No significant differences were observed in NTM infection-related comorbidities between men and women. In the younger age group (20–39 years old), the prevalence of respiratory and systemic diseases such as hypertension and diabetes was higher in the patient group than in the control group.

Conclusions

NTM infection is associated with several respiratory and systemic diseases that should be considered when providing medical care to patients with NTM infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02075-y.

Prognosis of nontuberculous mycobacterial pulmonary disease according to the method of microbiologic diagnosis

Microbiological criteria for nontuberculous mycobacterial pulmonary disease (NTM-PD) require cultures from two separate sputum or one non-sputum specimen. However, there is limited data on the progression of NTM-PD following non-sputum culture-based diagnosis. We compared the disease progression of NTM-PD diagnosed with non-sputum vs sputum cultures. We included 833 patients and divided them into sputum NTM isolation (n = 123), sputum NTM-PD (n = 558), and non-sputum NTM-PD groups (n = 152). Disease progression, defined as radiographic aggravation and therapy initiation, was compared between groups. The median observation time was 60.5 months (interquartile range, 31.4-96.0). The non-sputum NTM-PD group showed longer treatment-free survival (log-rank test; p = 0.009) and lower risk of treatment (adjusted hazard ratio [aHR] of sputum NTM-PD group, 1.36; 95% confidence interval (CI), 1.01-1.84) than the sputum NTM-PD group. The non-sputum NTM-PD group showed longer radiographic aggravation-free survival (Log-rank test; p = 0.015) and lower risk of radiographic aggravation (aHR of sputum NTM-PD group, 1.52; 95% CI, 1.06-2.19) than the sputum NTM-PD group. NTM-PD diagnosed using methods other than sputum culture showed a low risk of disease progression and progressed slower than NTM-PD diagnosed from a sputum culture. NTM-PD diagnosed using methods other than sputum culture may be a mild disease, not equivalent to NTM-PD diagnosed from sputum culture.

Isolation of Mycobacterium talmoniae from a patient with diffuse panbronchiolitis: a case report

BACKGROUND

Mycobacterium (M) talmoniae isolated from a patient with cystic fibrosis was first described in 2017, and cases of M. talmoniae remain exceedingly rare.

CASE PRESENTATION

A 51-year-old woman had respiratory symptoms for 10 years. Diffuse panbronchiolitis (DPB) was detected at the first visit at our hospital. A cavity lesion in the apex of the left lung was found, and sputum and bronchoalveolar lavage fluid were acid-fast bacillus (AFB) smear- and culture-positive besides Pseudomonas aeruginosa. M. talmoniae was finally identified, and the standard combination therapy for non-tuberculous mycobacteria (NTM) was administered for 2 y referring to the drug-susceptibility test. Thereafter, the AFB culture was negative, the wall thickness of the lung cavity was ameliorated, and oxygen saturation improved.

CONCLUSIONS

We encountered a rare case of M. talmoniae with DPB, for which standard combination therapy was effective. M. talmoniae may be considered a potential pathogen of lung disease, especially in patients with bronchiectatic lesions.

Comorbidities associated with nontuberculous mycobacterial disease in Japanese adults: a claims-data analysis

BACKGROUND

Nontuberculous mycobacterial (NTM) lung disease is one of a growing number of chronic health problems that is difficult to cure in aging societies. While it is important to be vigilant about associated comorbidities in order to provide better patient care, data on the prevalence of comorbidities stratified by country or region are scarce. We aimed to elucidate the comorbidities associated with NTM disease based on Japanese health insurance claims data.

METHODS

Cross-sectional analyses were performed using the claims data for 2014 provided by the Japan Medical Data Center Co., Ltd. Patients aged 20-75 years with ≥3 claims associated with NTM disease were identified and matched to 10 sex-and-age-matched controls that had never made a claim for NTM disease. Thirty-one comorbidities previously suspected to be associated with NTM disease were selected, and the prevalence of these comorbidities compared between cases and controls.

RESULT

Overall, 419 NTM patients (134 males and 285 females) and 4190 non-NTM controls were identified from the JMDC database. Aspergillosis, asthma, chronic heart failure, diffuse panbronchiolitis, gastroesophageal reflux, interstitial pneumonia, lung cancer, cancer other than breast, lung, ovary, or prostate cancer, and rheumatoid arthritis were associated with NTM disease in both males and females. Chronic obstructive pulmonary disease was associated with NTM in males while chronic kidney disease, osteoporosis, and Sjögren syndrome were associated with NTM in females.

CONCLUSION

NTM disease was associated with multiple comorbidities that should be considered when providing medical care to individuals with NTM disease.

The development of diffuse panbronchiolitis during the treatment with long-term, low-dose clarithromycin for chronic sinusitis

Diffuse panbronchiolitis (DPB) is a progressive inflammatory airway disease characterized by a chronic cough, copious sputum expectation, dyspnea, and chronic sinusitis. Owing to the long-term treatment of low-dose macrolides, the prognosis has been remarkably improved. However, in some cases, patients are refractory to macrolides, and the subsequent treatment strategies are controversial. We herein present a patient with the onset of DPB during treatment with long-term, low-dose clarithromycin (CAM) for chronic sinusitis who was successfully treated by switching to long-term treatment with normal-dose CAM. We should recognize that DPB may develop in patients with chronic sinusitis despite treatment with a long-term, low-dose macrolide. We also propose that increasing the dose of macrolide may be a useful strategy for treating refractory patients.

Diffuse bronchiectasis and airflow obstruction in granulomatosis with polyangiitis

Parenchymal lung nodes and diffuse intra-alveolar hemorrhage are the archetypal pulmonary manifestations of Granulomatosis with Polyangiitis (GPA). The occurrence of diffuse bronchiectasis and airflow obstruction during GPA is unusual. We report here 3 patients with GPA who developed diffuse bronchiectasis during follow-up. The airflow obstruction seemed then to evolve independently from the GPA itself and ultimately led to respiratory insufficiency. Bronchiectases promoted the occurrence of opportunistic infections, especially with atypical mycobacteria. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 81-84).

Characteristics of pulmonary Mycobacterium avium complex disease diagnosed later in follow-up after negative mycobacterial study including bronchoscopy

BACKGROUND

We occasionally experience cases suspected of pulmonary Mycobacterium avium complex (MAC) disease without positive bacterial cultures.

OBJECTIVE

To evaluate features of pulmonary MAC cases diagnosed later in the follow-up after negative intensive investigation.

METHODS

We defined and compared three groups; the first study negative (FSN) group, the first study positive (FSP) group, and MAC negative group. The FSN group consisted of patients negative for MAC isolation by bronchial washing performed between 2007 and 2011, but positive later. Patients with positive MAC cultures in the first study were incorporated into the FSP group. MAC negative group consisted of MAC suspects without MAC isolation in the follow-up.

RESULTS

Twenty-four patients were classified as FSN group, 61 as MAC negative group and 265 as FSP group. FSN group exhibited more solitary nodule pattern (n = 7 in FSN, n = 6 in FSP; p < 0.001) and less nodular/bronchiectatic (NB) diseases (n = 17 in FSN, n = 245 in FSP; p < 0.001). When limited to NB type, the FSP group had more cavitations (6% in FSN, 32% in FSP; p = 0.028). Patients with more than three lung lobes involved were more frequent in the FSN group compared with FSP group with negative sputum cultures (65% vs 34%; p = 0.014) and with MAC negative group (65% vs 28%; p = 0.009).

CONCLUSIONS

Patients diagnosed as pulmonary MAC disease in the follow-up duration tend to show solitary nodular pattern or NB pattern without cavitation. In FSN patients with NB pattern, more lung lobes were involved in the first study, suggesting subsequent MAC infection onto the underlying ectatic bronchi.