Non-tuberculous mycobacterial pulmonary infection presenting in a patient with unilateral pulmonary artery agenesis.

People who have structural or developmental lung disease are more likely to develop non-tuberculous mycobacterial infections. We present the case of a young man in his 30s who had unilateral pulmonary artery agenesis on the right side and presented with a 6-month history of productive cough and fever. His CT scan showed nodular and cavitating lesions on the right side, and sputum analysis confirmed infection with Mycobacterium chimaera He had to undergo modifications in his treatment, including a change from rifampicin to rifabutin due to drug interactions and his amikacin had to be stopped due to signs of vestibular toxicity. Using a multidisciplinary approach, we were able to formulate an appropriate drug regimen for him, and he is now under regular follow-up with infectious diseases and respiratory medicine.

Employing Multicolor Melting Curve Analysis to Rapidly Identify Non-Tuberculous Mycobacteria in Patients with Bronchiectasis: A Study from a Pulmonary Hospital in the Fuzhou District of China, 2018-2022.

Non-tuberculous mycobacteria (NTM) infection is common in bronchiectasis, with rising incidence globally. However, investigation into NTM in bronchiectasis patients in China remains relatively limited. This work aimed to identify and understand the features of NTM in bronchiectasis patient in Fuzhou district of China. The pulmonary samples were collected from 281 bronchiectasis patients with suspected NTM infection in Fuzhou, 2018-2022. MPB64 antigen detection was employed for the preliminary evaluation of NTM. Further NTM identification was realized using gene chip and gene sequencing. Among 281 patients, 172 (61.21%) patients were NTM-positive (58.72%) according to MPB64 antigen detection, with females (58.72%) outnumbering males (41.28%) and the highest prevalence in the age group of 46-65 years. In total, 47 NTM single infections and 3 mixed infections (1 Mycobacterium tuberculosis complex-M. intracellulare, 1 M. avium-M. intracellulare, and 1 M. abscessus-M. intracellulare) were identified through multicolor melting curve analysis (MMCA), which was compared with gene sequencing results. Both methods suggested Mycobacterium (M.) intracellulare, M. abscessus, and M. avium as the primary NTM species affecting bronchiectasis patients. M. intracellulare and M. abscessus were more frequent in females than males with the highest prevalence in the age group of 46-65 years according to MMCA. This research provides novel insights into the epidemiological and clinical features of NTM in bronchiectasis patients in Southeastern China. Significantly, M. intracellulare, M. abscessus, and M. avium were identified as the major NTM species, contributing to a better understanding and management of bronchiectasis accompanied by NTM infection.

[A case of silicosis complicated with non-tuberculous mycobacterium pulmonary disease].

Non-tuberculosis mycobacterium (NTM) refers to a general term for a large group of mycobacteria, excluding the mycobacterium tuberculosis and mycobacterium leprae, which is an opportunistic pathogen. NTM pulmonary disease and pulmonary tuberculosis have very similar clinical and imaging manifestations. Ordinary sputum tests can not distinguish between mycobacterium tuberculosis and NTM accurately, and it needs to be differentiated through detection methods such as mycobacterium culture medium, high-performance liquid chromatography, and molecular biology. During the diagnosis of occupational pneumoconiosis, a sandblasting and polishing worker's lung CT showed dynamic changes in infiltrating shadows and cavities in the right lung. A sputum drug sensitivity test showed NTM infection, but the patient refused treatment. After 20 months, the CT examination of the lung showed further enlargement of infiltrating shadows and cavities, and NTM bacterial identification showed intracellular mycobacterial infection. Amikacin, moxifloxacin, azithromycin, and ethambutol combined antibacterial treatment were given. Currently, the patient is still under treatment.

Disseminated Mycobacterium abscessus with endocarditis.

We present an uncommon case of endocarditis caused by Mycobacterium abscessus in an immunocompetent patient following a caesarean section. We discuss her turbulent admission course leading to her diagnosis following persistent M. abscessus bacteraemia, medical and surgical management, including a splenectomy and valve resection and repair, and subsequent prolonged course of combination antimicrobials for 24 months post valve surgery. The patient is alive 9 months after completing her treatment and 36 months after her valve surgery. We emphasise the importance of a multidisciplinary team approach in the management of such a complex case.

Clinical course of nontuberculous mycobacterial pulmonary disease in patients with rheumatoid arthritis.

OBJECTIVES: The impact of rheumatoid arthritis (RA) on nontuberculous mycobacterial pulmonary disease (NTM-PD) has not been well established. In this study, we investigated the clinical course of NTM-PD in patients with RA and the impact of RA on the prognosis of NTM-PD. METHODS: We analyzed patients who developed NTM-PD after being diagnosed with RA from January 2004 to August 2023 at a tertiary referral hospital in South Korea. The patient's baseline characteristics, clinical course, and prognosis were evaluated. An optimal matching analysis was performed to measure the impact of RA on the risk of mortality. RESULTS: During the study period, 18 patients with RA [median age, 68 years; interquartile range (IQR) 59-73; female, 88.9%] developed NTM-PD. The median interval between RA diagnosis and subsequent NTM-PD development was 14.8 years (IQR, 8.6-19.5). At a median of 30 months (IQR, 27-105) after NTM-PD diagnosis, 10 of 18 (55.6%) patients received anti-mycobacterial treatment for NTM-PD and 5 (50.0%) patients achieved microbiological cure. When matched to patients with NTM-PD but without RA, patients with both RA and NTM-PD had a higher risk of mortality (adjusted hazard ratio, 8.14; 95% confidence interval, 2.43-27.2). CONCLUSION: NTM-PD occurring after RA is associated with a higher risk of mortality than NTM-PD in the absence of RA.

Prevalence and Clinical Implications of Nontuberculous Mycobacteria Isolation and Infection among Patients with Bronchiectasis in the Jerusalem Area.

BACKGROUND: Bronchiectasis is an obstructive chronic lung disease characterized by structural changes in large and small airways, namely permanent widening of bronchial lumen resulting in chronic inflammation and infection. Nontuberculous mycobacteria (NTM) are environmental mycobacteria that may cause human infection or colonization with over 150 species identified to date. Bronchiectasis with NTM colonization or infection is often encountered but with varying prevalence and unknown clinical or prognostic significance. OBJECTIVES: To find the prevalence of NTM among patients with bronchiectasis in the Jerusalem district. To assess whether there were clinical differences between patients with bronchiectasis who were isolated with NTM and those without. METHODS: In this retrospective observational research study, we reviewed all computerized medical charts of patients over 18 years of age, who were diagnosed with bronchiectasis at Hadassah Medical Centers in Jerusalem between 2012 and 2017. We assessed the prevalence of NTM pulmonary disease. To compare patients with and without NTM, we reviewed and analyzed clinical, radiological, and microbiological data of all NTM patients and a group of controls in a 4:1 ratio. RESULTS: Prevalence of NTM among bronchiectasis patients was 5.1%, slightly lower than previously reported in Israel. We did not find clinically or radiological significant differences in patients with NTM disease compared to controls. This result included a similar number of exacerbations, hospitalization rates, number of lobes involved, and pulmonary function tests. CONCLUSIONS: Bronchiectasis patients with isolation of Pseudomonas aeruginosa experienced more exacerbations than patients with other isolates, consistent with previous studies.

Bilateral Nontuberculous Mycobacterial Otitis Media: A Case Report.

Established treatment strategies for nontuberculous mycobacterial (NTM) infections are currently lacking, and whether surgical treatment should be applied in combination with antibiotic therapy remains debatable. Here, we report a case of bilateral otitis media caused by Mycobacterium abscessusa, a highly antibiotic-resistant bacterium. Many reported cases of NTM otitis media are unilateral, in which hearing of the contralateral ear is preserved. In the present case, strategies to improve hearing outcomes were considered, as both ears were affected. A 27-year-old woman presented with bilateral otorrhea that had lasted for the past 9 months. Bacterial culture showed M. abscessus in both ears. Based on drug sensitivity tests, clarithromycin, amikacin, and imipenem were administered. Three days after treatment initiation, diseased tissues were removed from the right middle ear, which had impaired hearing. On day 38, otorrhea stopped in both ears, and the hearing improved. Computed tomography revealed air in both middle ears. No apparent recurrence was detected. Under the same antibiotic therapy, resolution of diseased tissues and improvement in hearing were similar between the ears with and without surgery, suggesting that surgery is not always necessary. This finding may be incorporated into the treatment guidelines for NTM infections in the future.

Rapid detection of clarithromycin resistance in clinical samples of nontuberculous mycobacteria by nucleotide MALDI-TOF MS.

The multidrug resistance of nontuberculous mycobacteria (NTM) poses a significant therapeutic challenge. Rapid and reliable drug susceptibility testing is urgently needed for evidence-based treatment decision, especially for macrolides. This study evaluated the utility of nucleotide matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (NMTMS) in detecting clarithromycin resistance. Sixty-four clinical isolates were identified to species by NMTMS, and mutations associated with clarithromycin resistance were detected. Twenty-three M. abscessus (MAB) isolates and 30 M. intracellulare isolates (including M. intracellulare alone and M. intracellulare in combination with other SGM species) were included for analysis. The predictive sensitivity of NMTMS in detecting clarithromycin resistance was 82.35% (95% CI, 56.57% to 96.20%), with an AUC of 0.89 (95% CI, 0.77 to 0.96) in all MAB and M. intracellulare (n = 53), and up to 93.33% (95% CI, 68.05% to 99.83%) in MAB alone (n = 23). The assay provides a rapid, high-throughput, and highly sensitive tool for detecting clarithromycin resistance in NTM, especially in MAB. Optimization of the panel is necessary to enhance diagnostic accuracy.

Evaluation of nucleotide MALDI-TOF-MS for the identification of Mycobacterium species.

Background: The accurate identification of the Mycobacterium tuberculosis complex (MTBC) and different nontuberculous mycobacteria (NTM) species is crucial for the timely diagnosis of NTM infections and for reducing poor prognoses. Nucleotide matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has been extensively used for microbial identification with high accuracy and throughput. However, its efficacy for Mycobacterium species identification has been less studied. The objective of this study was to evaluate the performance of nucleotide MALDI-TOF-MS for Mycobacterium species identification. Methods: A total of 933 clinical Mycobacterium isolates were preliminarily identified as NTM by the MPB64 test. These isolates were identified by nucleotide MALDI-TOF-MS and Sanger sequencing. The performance of nucleotide MALDI-TOF MS for identifying various Mycobacterium species was analyzed based on Sanger sequencing as the gold standard. Results: The total correct detection rate of all 933 clinical Mycobacterium isolates using nucleotide MALDI-TOF-MS was 91.64% (855/933), and mixed infections were detected in 18.65% (174/933) of the samples. The correct detection rates for Mycobacterium intracellulare, Mycobacterium abscessus, Mycobacterium kansasii, Mycobacterium avium, MTBC, Mycobacterium gordonae, and Mycobacterium massiliense were 99.32% (585/589), 100% (86/86), 98.46% (64/65), 94.59% (35/37), 100.00% (34/34), 95.65% (22/23), and 100% (19/19), respectively. For the identification of the MTBC, M. intracellulare, M. abscessus, M. kansasii, M. avium, M. gordonae, and M. massiliense, nucleotide MALDI-TOF-MS and Sanger sequencing results were in good agreement (k > 0.7). Conclusion: In conclusion, nucleotide MALDI-TOF-MS is a promising approach for identifying MTBC and the most common clinical NTM species.

Intestinal nontuberculous mycobacteria infection: A case report.

BACKGROUND: Intestinal nontuberculous mycobacteriosis due to nontuberculous mycobacteria infection has clinical manifestations similar to intestinal tuberculosis and inflammatory bowel disease, causing difficulties in clinical diagnosis. CASE PRESENTATION: A 42-year-old male patient was admitted to the Sino-Japanese Friendship Hospital of Jilin University in June 2021 for diarrhea and intermittent hematochezia since April 2021. He was diagnosed with inflammatory intestinal disease by colonoscopy and midtransverse colon biopsy. However, the symptoms did not relieve after 2 months of mesalazine treatment. In August 2021, the patient was admitted to the outpatient department for suspected "intestinal tuberculosis." A diagnosis of intestinal nontuberculous mycobacteriosis was confirmed based on pathology and nucleotide-based matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). After 2 weeks of antimycobacterial therapy, the patient's diarrhea was relieved, and hematochezia no longer appeared. In November 2021, recolonoscopy revealed scattered erosions and ulcers in ileocecal valve and ascending colon, while both nucleotide-based MALDI-TOF MS and next-generation sequencing could still detect Mycobacterium intracellulare. CONCLUSION: This study reported a patient with an intestinal nontuberculous mycobacteriosis diagnosed by colonoscopy biopsy and nucleotide-based MALDI-TOF MS, and symptoms were relieved after antimycobacterial treatment.

Non-tuberculous mycobacteria hybridisation profiles in the GenoType MTBDRplus assay: experience from a diagnostic routine of a high-throughput laboratory.

Introduction. Disease caused by non-tuberculous mycobacteria (NTM) is an emergent problem. Because NTM pulmonary disease and tuberculosis (TB) have similar clinical presentations, many cases of NTM may be misdiagnosed as TB before laboratory identification of the NTM species.Hypothesis/Gap Statement. Clinical laboratories should always perform differentiation between Mycobacterium tuberculosis complex (MTBC) and NTM to guide patients' correct treatment.Aim. To describe the characteristics and to identify mycobacterial isolates presumptively classified as MTBC by macroscopic characteristics in culture media that tested negative in GenoType MTBDRplus.Methodology. All cultures from February 2019 to December 2021 showing MTBC macroscopic characteristics were processed by GenoType MTBDRplus. MTBC-negative cultures underwent species identification by immunochromatography, line probe assays and PRA-hsp65. Patients' data were obtained from Brazilian surveillance systems.Results. Only 479 (3.1%) of 15 696 isolates presumptively identified as MTBC were not confirmed by GenoType MTBDRplus and were then subjected to identification. A total of 344 isolates were shown to be NTM, of which 309 (64.5%) and 35 (7.3%) were identified to the species and genus levels, respectively. Of the 204 NTM isolates with MTBC characteristics, the most frequent species were M. fortuitum (n=52, 25.5%), M. abscessus complex (MABC; n=27, 13.2%) and M. avium complex (MAC; n=26, 12.7%). Regarding the GenoType MTBDRplus results from NTM isolates, there were diverse hybridisation profiles with rpoB gene's different wild-type (WT) probes. Seventy-six (16.1%) of the 473 patients were classified as having NTM disease, the most frequent being MAC (n=15, 19.7%), MABC (n=13, 17.1%), M. kansasii (n=10, 13.2%) and M. fortuitum (n=6, 7.9%).Conclusion. Because the signs and symptoms of pulmonary TB are similar to those of pulmonary mycobacteriosis and treatment regimens for TB and NTM are different, identifying the disease-causing species is paramount to indicate the correct management. Thus, in the laboratory routine, when an isolate presumptively classified as MTBC is MTBC-negative, it is still essential to perform subsequent identification.

Nontuberculous Mycobacterial Infections in Pediatric Solid Organ Transplant and Hematopoietic Cell Transplant Recipients.

The diagnosis of nontuberculous mycobacterial infections is challenging in pediatric solid organ transplant and hematopoietic cell transplant recipients due to the absence of specific clinical manifestations, limitations of sampling, prolonged times for culture and identification, and difficulty discerning colonization from clinical disease. Treatment is dependent on the nontuberculous mycobacterial species, disease type, and pattern of drug resistance. Treatment of nontuberculous mycobacterial infections involves prolonged durations of therapy using multiple medications, which are limited by toxicities and drug-drug interactions.

Subcutaneous infection caused by Mycobacterium abscessus following botulinum toxin injections: A case report and literature review.

BACKGROUND: The rapid development of cosmetic injections has led to an increased incidence of nontuberculous mycobacterial (NTM) infection. PATIENTS AND METHODS: Here, we presented a case of cutaneous Mycobacterium abscessus infection subsequent to botulinum toxin injection for treating masseter hypertrophy, and reviewed the literature on skin and soft tissue infections caused by NTM after cosmetic injections. RESULTS AND CONCLUSIONS: The patient underwent surgical excision and regular antibiotic therapy and has had nearly 2 months of follow-up without any signs of infection. The diagnosis and treatment of NTM infection have always been challenging, and further research is needed to standardize and guide the treatment.

Extensive Bilateral Cervicofacial Lymphadenitis Caused by Atypical Mycobacterium.

Non-tuberculous mycobacterial (NTM) lymphadenitis typically presents as a unilateral, non-tender, slowly enlarging cervical, submandibular, or pre-auricular lymph node in children. Disseminated NTM infection is most often seen in immunocompromised children. Here, we present an unusual case of extensive bilateral cervical and retropharyngeal lymphadenitis caused by Mycobacterium Avium Complex (MAC) in an ostensibly immunocompetent pediatric patient.

Evaluation of mycobacteria infection prevalence and optimization of the identification process in North Sardinia, Italy.

IMPORTANCE: Mycobacterial infection is a major threat to public health worldwide. Accurate identification of infected species and drug resistance detection are critical factors in treatment. We focused on shortening the turn-around time of identifying mycobacteria species and antibiotic resistance tests.

Outcomes of Intermittent Multidrug IV Therapy for Refractory Mycobacterium abscessus Pulmonary Disease.

BACKGROUND: No studies have reported therapies for the treatment of patients with refractory Mycobacterium abscessus pulmonary disease (MAB-PD). We implemented intermittent multidrug IV therapy (IMIT) through repeated hospitalizations for patients with MAB-PD who were refractory to antibiotics for more than 12 months. RESEARCH QUESTION: What are the effects of IMIT on patients with refractory MAB-PD? STUDY DESIGN AND METHODS: The IV antibiotics administered for IMIT included amikacin, imipenem, and tigecycline, and the outcomes for 36 patients who underwent IMIT for refractory MAB-PD were evaluated. Patients were repeatedly hospitalized and administered IMIT on recurrent symptoms or radiographic evidence of deterioration, while maintaining oral/inhaled antibiotics. RESULTS: Of the 36 patients, 26 (72%) had M abscessus subspecies abscessus (herein, M abscessus)-PD, and 10 (28%) had M abscessus subspecies massiliense (herein, M massiliense)-PD. The median number of hospitalizations for IMIT was two (interquartile range, 1-3) for patients with M abscessus-PD and one (interquartile range, 1-2) for patients with M massiliense-PD. At least one negative culture result and culture conversion were observed in 62% and 12% of patients with M abscessus-PD, and in 80% and 60% of patients with M massiliense-PD, respectively. Symptomatic improvement was observed in all patients, and radiologic improvement, including cavity amelioration or no deterioration, was observed in 42% and 70% of patients with M abscessus-PD and with M massiliense-PD, respectively. No resistance to clarithromycin or amikacin was acquired. INTERPRETATION: IMIT with intermittent hospitalization can be a beneficial palliative treatment for patients with refractory MAB-PD. This therapy alleviated symptoms, slowed radiologic progression, and reduced the bacterial burden in some patients. However, radiologic and microbiological responses to IMIT were more apparent in M massiliense-PD than in M abscessus-PD.

The diagnosis of nontuberculous cervicofacial lymphadenitis: A systematic review.

BACKGROUND: Nontuberculous mycobacterial cervicofacial lymphadenitis (NTMCL) is an uncommon condition detected in young immunocompetent children who typically present with a nontender neck mass. Various tests have been proposed to assist in the work-up of suspected NTMCL, with varying diagnostic utility. This systematic review investigates the sensitivity of the various diagnostic methods used in the work-up of pediatric NTMCL. METHODS: A systematic review in accordance with PRISMA guidelines was performed using the Pubmed, EMBASE, and Web of Science databases. Searches were filtered for English language studies published prior to 05/10/22. Studies meeting criteria included studies featuring 15+ pediatric patients with confirmed or suspected NTMCL. Studies with any reported diagnostic methodology used in the workup of NTMCL were included. RESULTS: Of 836 abstracts/articles reviewed, 21 studies met inclusion criteria. Diagnostic methods included culture(n = 11 studies), PPD-Tb(Tuberculin)(n = 12), PPD-Scrofulaceum, -Avium, or -Kansasii(n = 6), staining techniques(n = 4), IGRA(n = 3), and ultrasound(n = 2). All studies had an overall low risk of bias. Among patients confirmed to have NTMCL based on PCR and/or culture, the most sensitive tests were PPD-A(0.94, 95 % CI 0.91 to 0.97; n = 210 patients) and PPD-S(0.75, 95 % CI 0.68 to 0.81; n = 171). Auramine and Ziehl-Neelsen staining techniques had moderately high sensitivity(0.85 and 0.60 respectively), though were limited by low patient numbers(n = 20). PPD-Tb(0.45, 95 % CI 0.39 to 0.50; n = 300) and IGRA(0.02; 95 % CI 0 to 0.06; n = 48) demonstrated poor sensitivity. Among patients suspected to have NTM lymphadenitis based on global assessment, the most sensitive tests included combined PPD-S + A + K(0.92, 95 % CI 0.86 to 0.98; n = 85), PCR(0.82, 95 % CI 0.75 to 0.88; n = 136), and PPD-A(0.72, 95 % CI 0.62 to 0.81; n = 84). Culture showed a sensitivity of 0.54(95 % CI 0.50 to 0.58; n = 494). PPD-K, PPD-S, IGRA, and staining techniques demonstrated lower sensitivity. CONCLUSIONS: This systematic review is the largest study investigating the sensitivity of the various diagnostic methods used in the work-up of pediatric NTMCL. Patients with clinical suspicion for NTMCL and a positive PPD-Tb should first have tuberculous lymphadenitis ruled out with IGRA. Patients with a positive PPD-Tb and negative IGRA and high clinical suspicion for NTMCL can undergo presumptive surgical intervention. Patients with a negative PPD-Tb can undergo NTM antigen skin testing if available, or if high clinical suspicion exists, surgical intervention to reduce tissue burden and elicit additional tissue data.