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Journal of Microbiological Methods Aug 2023There is an unmet need for tools that permit diagnosis of Tuberculosis (TB) that are affordable, low-tech, and can differentiate Mycobacterium tuberculosis (M.tb) from...
There is an unmet need for tools that permit diagnosis of Tuberculosis (TB) that are affordable, low-tech, and can differentiate Mycobacterium tuberculosis (M.tb) from non-tuberculous mycobacteria (NTM). In this study, we have developed a strip-based assay to detect the activity of a unique Carbapenem Resistance Factor A (CrfA) enzyme present only in M.tb. The strip comprises of PVDF (Polyvinylidene fluoride) membrane that has an immobilized anti-CrfA antibody to capture the CrfA enzyme from M.tb lysate. Lysate of mycobacteria is applied to the strip, washed, and incubated in the presence of chromogenic reporter dye which is a substrate for CrfA. A change in the color of the dye that is readily visible to the naked eye is the readout. We evaluated lysates from M.tb and various NTMs namely, M. abscessus, M. chelonae, M. avium, M. obuense, M. paraintracellulare, M. kansasi, including the patient-derived sputum samples. The strip assay selectively identified only those samples containing M.tb. Based on this evidence, this new assay enables the identification and differentiation of M.tb from NTMs in patient sputum samples. As this tool can be simple to use, therefore has the potential to serve the unmet need for diagnosis of TB and NTM infections in resource-limited settings.
Topics: Humans; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; Tuberculosis; Mycobacterium Infections, Nontuberculous; Sputum
PubMed: 37437716
DOI: 10.1016/j.mimet.2023.106781 -
Anais Brasileiros de Dermatologia 2023
PubMed: 37407333
DOI: 10.1016/j.abd.2022.12.005 -
Surgical Case Reports Jul 2023Mycobacterium chelonae, a nontuberculous mycobacterium, commonly causes skin, soft tissue, eye, pulmonary, catheter-related, and post-surgical infections in patients...
BACKGROUND
Mycobacterium chelonae, a nontuberculous mycobacterium, commonly causes skin, soft tissue, eye, pulmonary, catheter-related, and post-surgical infections in patients with immunosuppression or trauma. M. chelonae breast infections are rare, and most cases occur following cosmetic surgery. Here, we report the first case of spontaneous breast abscess due to M. chelonae.
CASE PRESENTATION
A 22-year-old Japanese woman presented at our hospital with swelling and pain in the right breast for the past 2 weeks without any fever. She had a 19-month-old child and stopped breastfeeding 1 month after giving birth. The patient had no history of trauma or breast surgeries, no family history of breast cancer, and was not immunocompromised. Breast ultrasonography revealed a heterogeneous hypoechoic lesion with multiple fluid-filled areas suspected to be abscesses. Dynamic contrast-enhanced magnetic resonance imaging revealed a 64 × 58 × 62 mm, ill-defined, high-signal-intensity lesion with multiple ring enhancements in the upper half of the right breast. The first diagnosis was inflammatory breast cancer or granulomatous mastitis with abscess. A core needle biopsy led to drainage of pus. Gram staining did not reveal any bacteria in the pus, but the colonies from the biopsy grew on blood and chocolate agar cultures. Mass spectrometry detected M. chelonae in these colonies. Histopathological findings revealed mastitis without malignancy. The patient's treatment regimen was oral clarithromycin (CAM) based on susceptibility. Three weeks later, although the pus had reduced, the induration in the breast did not resolve; therefore, multidrug antibiotic treatment was initiated. The patient received amikacin and imipenem infusion therapy for 2 weeks, followed by continuation of CAM. Three weeks later, tenderness in the right breast recurred with slight pus discharge. Hence, minocycline (MINO) was added to the treatment. The patient stopped CAM and MINO treatment 2 weeks later. There was no recurrence 2 years after treatment.
CONCLUSION
We report a case of M. chelonae breast infection and abscess formation in a 22-year-old Japanese woman without obvious risk factors. M. chelonae infection should be considered in cases of intractable breast abscess, even in patients without immunosuppression or trauma.
PubMed: 37405585
DOI: 10.1186/s40792-023-01706-8 -
Journal of Clinical Microbiology Jul 2023Macrolides are a mainstay of therapy for infections due to nontuberculous mycobacteria (NTM). Among rapidly growing mycobacteria (RGM), inducible macrolide resistance is...
Macrolides are a mainstay of therapy for infections due to nontuberculous mycobacteria (NTM). Among rapidly growing mycobacteria (RGM), inducible macrolide resistance is associated with four chromosomal 23S rRNA methylase () genes. Beginning in 2018, we detected high-level inducible clarithromycin resistance (MICs of ≥16μg/mL) in clinical isolates of Mycobacterium chelonae, an RGM species not previously known to contain genes. Using whole-genome sequencing, we identified a novel plasmid-mediated gene. This gene, designated (55), exhibits <65% amino acid identity to previously described RGM genes. Two additional chromosomal (55) alleles, with sequence identities of 81% to 86% to (55), were also identified and designated (55) and (55). The (55) is part of a transposon. The (55) allele variant is located on a putative 137-kb conjugative plasmid, pMchErm55. Evaluation of 133 consecutive isolates from 2020 to 2022 revealed 5 (3.8%) with (55). The e(55) gene was also identified in public data sets of two emerging pathogenic pigmented RGM species: Mycobacterium iranicum and Mycobacterium obuense, dating back to 2008. In both species, the gene appeared to be present on plasmids homologous to pMchErm55. Plasmid-mediated macrolide resistance, not described previously for any NTM species, appears to have spread to multiple RGM species. This has important implications for antimicrobial susceptibility guidelines and treatment of RGM infections. Further spread could present serious consequences for treatment of other macrolide-susceptible RGM. Additional studies are needed to determine the transmissibility of pMchErm55 and the distribution of (55) among other RGM species.
Topics: Humans; Anti-Bacterial Agents; Macrolides; Mycobacterium chelonae; Drug Resistance, Bacterial; Clarithromycin; Nontuberculous Mycobacteria; Mycobacterium; Plasmids; Microbial Sensitivity Tests; Mycobacterium Infections, Nontuberculous
PubMed: 37347171
DOI: 10.1128/jcm.00428-23 -
Dermatologie (Heidelberg, Germany) Sep 2023We report the case of a healthy young man who presented to our clinic with itchy skin lesions in the area of a tattoo on the back of the left hand. Bioptic and...
We report the case of a healthy young man who presented to our clinic with itchy skin lesions in the area of a tattoo on the back of the left hand. Bioptic and cultural confirmation of the pathogens led to the diagnosis of Mycobacterium chelonae infection. We initiated antibiotic therapy using azithromycin and linezolid with good response. Our case underlines that besides allergic skin reactions, infections as a complication after tattooing should also be included in the differential diagnosis.
Topics: Humans; Male; Adult; Mycobacterium Infections, Nontuberculous; Tattooing; Skin Diseases, Bacterial; Anti-Bacterial Agents; Mycobacterium chelonae; Azithromycin; Linezolid; Biopsy; Skin; Treatment Outcome
PubMed: 37341750
DOI: 10.1007/s00105-023-05173-y -
Infection Control and Hospital... Dec 2023A pseudo-outbreak of bronchoscopy-associated and was traced to contaminated ice machine water and ice. A nonsterile ice bath was used to cool uncapped, sterile, saline...
A pseudo-outbreak of bronchoscopy-associated and was traced to contaminated ice machine water and ice. A nonsterile ice bath was used to cool uncapped, sterile, saline syringes used to slow procedural bleeding. Joining the growing evidence of bronchoscopy pseudo-outbreaks, our investigation describes several lessons for future prevention.
Topics: Humans; Bronchoscopy; Disease Outbreaks; Ice; Mycobacterium chelonae; Mycobacterium Infections, Nontuberculous; Water Microbiology; Cross Infection
PubMed: 37272469
DOI: 10.1017/ice.2023.101 -
Journal of Infection and Chemotherapy :... Sep 2023The prevalence of nontuberculous mycobacteria (NTM) infections is increasing worldwide. Although NTM can affect extrapulmonary organs, studies on the clinical...
INTRODUCTION
The prevalence of nontuberculous mycobacteria (NTM) infections is increasing worldwide. Although NTM can affect extrapulmonary organs, studies on the clinical characteristics of extrapulmonary NTM are rare.
METHODS
We retrospectively analyzed patients who were newly diagnosed with NTM infections at Hiroshima University Hospital between 2001 and 2021 to investigate species distribution, infected sites, and risk factors of extrapulmonary NTM compared to pulmonary NTM.
RESULTS
Of the 261 NTM infections, 9.6% and 90.4% had extrapulmonary and pulmonary NTM, respectively. The mean ages of patients with extrapulmonary and pulmonary NTM were 53.4 and 69.3 years, 64.0% and 42.8% were male, 36.0% and 9.3% received corticosteroids, 20.0% and 0% had acquired immune deficiency syndrome (AIDS), and 56.0% and 16.1% had any immunosuppressive conditions, respectively. Younger age, corticosteroid use, and AIDS were associated with extrapulmonary NTM. In pulmonary NTM, Mycobacterium avium complex (MAC) accounted for 86.4% of NTM species, followed by M. abscessus complex (4.2%), whereas in extrapulmonary NTM, M. abscessus complex, MAC, M. chelonae, and M. fortuitum accounted for 36.0%, 28.0%, 12.0%, and 8.0%, respectively. Compared to pulmonary NTM, extrapulmonary NTM were significantly more likely to be rapid-growing mycobacteria (RGM) (56.0% vs. 5.5%). The most common sites of infection were the skin and soft tissues (44.0%), followed by the blood (20.0%), tenosynovium, and lymph nodes (12.0%).
CONCLUSION
Younger age and immunosuppressive conditions are associated with extrapulmonary NTM, with a higher prevalence of RGM in extrapulmonary NTM than in pulmonary NTM. These results provide a better understanding of extrapulmonary NTM.
Topics: Humans; Male; Middle Aged; Aged; Female; Retrospective Studies; Acquired Immunodeficiency Syndrome; Japan; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Mycobacterium avium Complex; Pneumonia
PubMed: 37209842
DOI: 10.1016/j.jiac.2023.05.013 -
Journal of Clinical Tuberculosis and... Aug 2023is a species of nontuberculous mycobacteria that typically causes localized cutaneous disease in immunocompetent hosts. There have been few reports of disseminated...
BACKGROUND
is a species of nontuberculous mycobacteria that typically causes localized cutaneous disease in immunocompetent hosts. There have been few reports of disseminated infections in immunocompetent individuals which have often been associated with invasive medical procedures.
CASE PRESENTATION
In this report, we describe a 43-year-old immunocompetent female with an implanted venous access device who presented with skin lesions increasing in size and frequency over the course of five months despite antimicrobial therapy. A diagnosis was not made until mycobacterial culture from a skin biopsy grew .
CONCLUSION
Disseminated cutaneous infection can be a rare complication of indwelling venous catheterization among immunocompetent patients.
PubMed: 37139480
DOI: 10.1016/j.jctube.2023.100373 -
Annals of the American Thoracic Society Aug 2023Population-based data on the epidemiology of nontuberculosis mycobacterial (NTM) infections are limited, particularly with respect to variation in NTM infection among...
Population-based data on the epidemiology of nontuberculosis mycobacterial (NTM) infections are limited, particularly with respect to variation in NTM infection among racial groups and socioeconomic strata. Wisconsin is one of a handful of states where mycobacterial disease is notifiable, allowing large, population-based analyses of the epidemiology of NTM infection in this state. To estimate the incidence of NTM infection in Wisconsin adults, describe the geographic distribution of NTM infection across the state, identify the frequency and type of infection caused by different NTM species, and investigate associations between NTM infection and demographics and socioeconomic status. We conducted a retrospective cohort study using laboratory reports of all NTM isolates from Wisconsin residents submitted to the Wisconsin Electronic Disease Surveillance System from 2011 to 2018. For the analyses of NTM frequency, multiple reports from the same individual were enumerated as separate isolates when nonidentical, collected from different sites or collected more than one year apart. A total of 8,135 NTM isolates from 6,811 adults were analyzed. complex accounted for 76.4% of respiratory isolates. The group was the most common species isolated from skin and soft tissue. The annual incidence of NTM infection was stable over the study period (from 22.1 per 100,000 to 22.4 per 100,000). The cumulative incidence of NTM infection among Black (224 per 100,000) and Asian (244 per 100,000) individuals was significantly higher compared with that among their White counterparts (97 per 100,000). Total NTM infections were significantly more frequent ( < 0.001) in individuals from disadvantaged neighborhoods, and racial disparities in the incidence of NTM infection generally remained consistent when stratified by measures of neighborhood disadvantage. More than 90% of NTM infections were from respiratory sites, with the vast majority caused by complex. Rapidly growing mycobacteria predominated as skin and soft tissue pathogens and were important minor respiratory pathogens. We found a stable annual incidence of NTM infection in Wisconsin between 2011 and 2018. NTM infection occurred more frequently in non-White racial groups and in individuals experiencing social disadvantage, suggesting that NTM disease may be more frequent in these groups as well.
Topics: Adult; Humans; Nontuberculous Mycobacteria; Wisconsin; Retrospective Studies; Mycobacterium Infections, Nontuberculous; Mycobacterium avium Complex
PubMed: 36812384
DOI: 10.1513/AnnalsATS.202205-425OC