Mycobacterium Immunogenum Research Articles

Dominant Circulating Cell-free Mycobacterial Proteins in In-use Machining Fluid and their Antigenicity Potential.

Occupational exposure to industrial Metalworking Fluid (MWF) colonized by Mycobacterium immunogenum (MI) has been associated with immune lung disease hypersensitivity pneumonitis (HP) in machinists. This warrants regular fluid monitoring for early detection of mycobacterial proteins, especially those with antigenic potential. To detect and identify dominant MI proteins and antigens directly from the field-drawn in-use MWF using an integrated immunoproteomic-immunoinformatic approach. An MI-positive MWF selected by DNA-based screening of several field-drawn MWF samples was cultured to isolate the colonizing strain and profiled for dominant circulating cell-free (ccf) MI proteins, including antigens using an integrated immunoproteomic (1D- and 2Dgel fractionation of seroreactive proteins combined with shotgun proteomic analysis using LC-MS/MS) and immunoinformatic strategy. A new MI strain (MJY-27) was identified. The gel fractionated MI protein bands (1Dgel) or spots (2D-gel) seroreactive with anti-MI sera probes (Rabbit and Patient sera) yielded 86 MI proteins, 29 of which showed peptide abundance. T-cell epitope analysis revealed high (90-100%) binding frequency for HLA-I & II alleles for 13 of the 29 proteins. Their antigenicity analysis revealed the presence of 6 to 37 antigenic determinants. Interestingly, one of the identified candidates corresponded to an experimentally validated strong B- and T-cell antigen (AgD) from our laboratory culture-based studies. This first report on dominant proteins, including putative antigens of M. immunogenum prevalent in field in-use MWF, is a significant step towards the overall goal of developing fluid monitoring for exposure and disease risk assessment for HP development in machining environments.

Mycobacterium immunogenum acquisition from hospital tap water: a genomic and epidemiologic analysis.

We identified 23 cases of Mycobacterium immunogenum respiratory acquisition linked to a colonized plumbing system at a new hospital addition. We conducted a genomic and epidemiologic investigation to assess for clonal acquisition of M. immunogenum from hospital water sources and improve understanding of genetic distances between M. immunogenum isolates. We performed whole-genome sequencing on 28 M. immunogenum isolates obtained from August 2013 to July 2021 from patients and water sources on four intensive care and intermediate units at an academic hospital. Study hospital isolates were recovered from 23 patients who experienced de novo respiratory isolation of M. immunogenum and from biofilms obtained from five tap water outlets. We also analyzed 10 M. immunogenum genomes from previously sequenced clinical (n = 7) and environmental (n = 3) external control isolates. The 38-isolate cohort clustered into three clades with pairwise single-nucleotide polymorphism (SNP) distances ranging from 0 to 106,697 SNPs. We identified two clusters of study hospital isolates in Clade 1 and one cluster in Clade 2 for which clinical and environmental isolates differed by fewer than 10 SNPs and had less than 0.5% accessory genome variation. A less restrictive combined threshold of 40 SNPs and 5% accessory genes reliably captured additional isolates that met clinical criteria for hospital acquisition, but 12 (4%) of 310 epidemiologically unrelated isolate pairs also met this threshold. Core and accessory genome analyses confirmed respiratory acquisition of multiple clones of M. immunogenum from hospital water sources to patients. When combined with epidemiologic investigation, genomic thresholds accurately distinguished hospital acquisition.

Significance of early diagnosis and surgical management in treating Mycobacterium immunogenum-related pyogenic extensor tenosynovitis: a case report

BackgroundNon-tuberculous mycobacteria (NTM) are environmental organisms that are increasingly contributing to human infections. Mycobacterium immunogenum, a variant of NTM discovered in 2001, is a rapidly growing mycobacterium that exhibits multidrug resistance. Reports of infections caused by this organism, particularly tenosynovitis in the musculoskeletal system, are limited.Case presentationA 71-year-old female with vesicular pemphigus, undergoing immunosuppressive therapy, presented with a progressively enlarging tumour on the dorsum of her right hand, along with erythematous papules that extended across her right forearm. The specimens of skin tissues and blood cultures revealed the presence of M. immunogenum. Magnetic resonance imaging evaluation led to the diagnosis of pyogenic extensor tenosynovitis. A multidrug regimen, comprising amikacin and clarithromycin, was initiated, followed by synovectomy. The patient underwent a course of 180 days of antimicrobial therapy and demonstrated no signs of disease recurrence one year after treatment completion.ConclusionEarly diagnosis and surgical intervention are crucial to prevent the adverse prognostic implications of pyogenic extensor tenosynovitis caused by M. immunogenum. Effective management requires precise microbial identification and susceptibility testing, necessitating collaborative engagement with microbiological laboratories.

Differential Immunogenicity and Lung Disease-Inducing Potential of Mycobacterium immunogenum Genotypes and Impact of Co-Exposure with Pseudomonas: Optimizing a Mouse Model of Chronic Hypersensitivity Pneumonitis.

Mycobacterium immunogenum (MI) colonizing metalworking fluids (MWFs) has been associated with chronic hypersensitivity pneumonitis (HP) in machinists. However, it is etiologically unclear why only certain mycobacteria-contaminated fluids induce this interstitial lung disease. We hypothesized that this may be due to differential immunogenicity and the HP-inducing potential of MI strains/genotypes as well as the confounding effect of co-inhaled endotoxin-producers. To test this hypothesis, we optimized a chronic HP mouse model in terms of MI antigen dose, timepoint of sacrifice, and form of antigen (cell lysates vs. live cells) and compared six different field-isolated MI strains. Overall, MJY10 was identified as the most immunogenic and MJY4 (or MJY13) as the least immunogenic genotype based on lung pathoimmunological changes as well as Th1 cellular response (IFN-γ release). Infection with MI live cells induced a more severe phenotype than MI cell lysate. Co-exposure with Pseudomonas fluorescens caused a greater degree of lung innate immune response and granuloma formation but a diminished adaptive (Th1) immune response (IFN-γ) in the lung and spleen. In summary, this study led to the first demonstration of differential immunogenicity and the disease-inducing potential of field strains of MI and an interfering effect of the co-contaminating Pseudomonas. The improved chronic MI-HP mouse model and the identified polar pair of MI strains will facilitate future diagnostic and therapeutic research on this poorly understood environmental lung disease.

Complete genome sequence of Mycobacterium immunogenum strain C14-1.MIM isolated from a hospitalized lung transplant recipient.

Mycobacterium immunogenum is a rapidly growing nontuberculous mycobacteria species that can cause healthcare-associated infections. We report the complete genome of C14-1.MIM, isolated via culture of a respiratory specimen obtained from a hospitalized lung transplant recipient. The circular chromosome contains 5,407,919 bp with a G + C content of 64.24% and 5,217 coding sequences.

Hypersensitivity pneumonitis due to metal working fluids: Detection of specific IgG antibodies to microbial antigens

Occupational exposure to microbially contaminated metal working fluids (MWF) can cause hypersensitivity pneumonitis (HP). An important step in the diagnosis of HP is to identify the triggering antigen by detection of corresponding specific IgG antibodies (sIgG). As commercial sIgG tests are currently not available, protein antigens were prepared from MWF-workplace samples and from MWF-typical bacterial isolates. In 57 % of suspected HP-cases (n = 30) elevated sIgG concentrations were measured to at least one MWF-relevant antigen, of which Mycobacterium immunogenum was most prominent (88 %), followed by Pseudomonas oleovorans and Pseudomonas spec (82 % each), MWF-antigen mix and Pseudomonas alcaliphila (65 % each). Elevated sIgG concentrations to other microorganisms were measured to Micropolyspora faeni (82 %) and Aureobasidium pullulans (77 %). Correlation of sIgG values of all tested microbial antigens showed a significant relationship of MWF-antigen mixture to Pseudomonas antigens, but a low correlation to moulds. These newly prepared MWF-antigens are useful tools for the diagnosis of patients with suspected MWF-HP and are available for further investigations.

In vitro susceptibility patterns for rapidly growing nontuberculous mycobacteria in the United States

Antimicrobial susceptibility testing for rapidly growing mycobacteria (RGM) is uncommon or only performed in large reference laboratories. Here we developed a cumulative antibiogram for 14 RGM using the largest sample size to date (N = 3860). All RGM showed 82% to 100% susceptibility to amikacin. Mycobacterium abscessus showed low percentages of susceptibility to most antimicrobials; of antimicrobials without interpretations, the minimum inhibitory concentration-90 for clofazimine was low (≤0.5mg/L). All three subspecies had ≤2.6% rrl resistance mutations, however intact erm(41) was detected in 70% to100% of M. abscessus abscessus and bolletii. Mycobacterium chelonae had a similar susceptibility pattern to M. abscessus subsp. massiliense and Mycobacterium immunogenum except that it was susceptible to tobramycin (87%). Mycobacterium fortuitum complex and similar organisms showed higher frequency of susceptibility to fluoroquinolones, beta-lactams, linezolid, and trimethoprim/sulfamethoxazole. Although relatively small published RGM antibiograms showed substantial variance, a comprehensive antibiogram can help influence treatment and monitoring patterns of resistance.

Is There an Acceptable Level of Nontuberculous Mycobacterium in a Heater-cooler Water Tank?

<h3>Background</h3> Heater-cooler units (HCUs) are frequently used in cardiac surgery and have been implicated in nontuberculous Mycobacterium (NTM) infections. A patient developed a NTM infection after undergoing cardiac surgery and the HCU was evaluated for an epidemiologic link. This study assesses challenges of interpreting significance of low numbers of colony forming units (CFU) of NTM in the water tank of a HCU. <h3>Methods</h3> The HCU was removed from service. A 220 milliliter (ml) water sample was collected from the tank drain of the HCU after disinfection and sent to an outside laboratory to evaluate for NTM. NTM was identified in the initial specimen. The HCU was re-disinfected and re-cultured. Repeat cultures grew the same NTM as the first sample. Disinfection practices were reviewed and all HCU disinfection aligned with manufacturer's instructions for use. With continued growth of NTM, the HCU was sent to the manufacturer and internal water paths were replaced. Upon return of the HCU to the hospital, it was disinfected and cultured. <h3>Results</h3> Initial water sample grew 14 CFU/ml of Mycobacterium immunogenum. This species did not match the patient's clinical isolate. Repeat culture after disinfection grew 36 CFU/ml of the same organism. Water cultures obtained after the manufacturer replaced the HCU's internal water paths grew 14 CFU/ml of the same NTM. After review of Centers for Disease Control and Prevention (CDC) guidance regarding acceptable levels of colony counts in dialysis and endoscopes, in addition to no epidemiological link of this NTM species to any patient infections, the HCU was returned to service. <h3>Conclusions</h3> Currently, there is no standardized threshold for NTM in HCUs or in municipal water supply. The use of filters may not eliminate all NTM in tap water. A standardized threshold needs to be set for allowable limits of recovered NTM in HCUs in order to return to service safely.

Infection with Mycobacterium immunogenum after an injection lipolysis procedure.

Infection with Mycobacterium immunogenum after an injection lipolysis procedure.

A genomic analysis of Mycobacterium immunogenum strain CD11_6 and its potential role in the activation of T cells against Mycobacterium tuberculosis

BackgroundMycobacterium tuberculosis (Mtb) is an etiological agent of tuberculosis (TB). Tuberculosis is a mounting problem worldwide. The only available vaccine BCG protects the childhood but not adulthood form of TB. Therefore, efforts are made continuously to improve the efficacy of BCG by supplementing it with other therapies. Consequently, we explored the possibility of employing Mycobacterium immunogenum (Mi) to improve BCG potential to protect against Mtb.ResultsWe report here the genome mining, comparative genomics, immunological and protection studies employing strain CD11_6 of Mi. Mycobacterium immunogenum was isolated from duodenal mucosa of a celiac disease patient. The strain was whole genome sequenced and annotated for identification of virulent genes and other traits that may make it suitable as a potential vaccine candidate. Virulence profile of Mi was mapped and compared with two other reference genomes i.e. virulent Mtb strain H37Rv and vaccine strain Mycobacterium bovis (Mb) AFF2122/97. This comparative analysis revealed that Mi is less virulent, as compared to Mb and Mtb, and contains comparable number of genes encoding for the antigenic proteins that predict it as a probable vaccine candidate. Interestingly, the animals vaccinated with Mi showed significant augmentation in the generation of memory T cells and reduction in the Mtb burden.ConclusionThe study signifies that Mi has a potential to protect against Mtb and therefore can be a future vaccine candidate against TB.

785. Treatment of Mycobacterium immunogenum Skin and Soft-Tissue Infections: A Case in a Peritoneal Dialysis Patient

Background Mycobacterium immunogenum is a somewhat recently identified species of rapidly growing nontuberculous mycobacteria, genetically related to M. abscessus and M. chelonae. Resistance patterns of rapidly growing nontuberculous mycobacterium species can make them difficult to treat. This is particularly true of M. immunogenum, in part due to the infrequency of reported cases of human infection and limited data to guide therapy.MethodsWe present here a case of M. immunogenum skin and soft-tissue infection at the site of insertion of a peritoneal dialysis catheter in a patient with end-stage renal disease. He initially presented with nodular subcutaneous lesions around his catheter site that progressed through oral antibiotics. This led to sampling which confirmed the diagnosis of M. immunogenum. We conducted a review of the literature to identify previously reported cases of M. immunogenum, including skin and soft-tissue infections, and used these data to guide management.ResultsWe reviewed 11 reports (cases and case series) of Mycobacterium immunogenum in the literature. Susceptibilities often take weeks to return, and so empiric therapy is based on case series, and then later adjusted based on susceptibilities. Patients received combined antimicrobial regimens with durations of 2 weeks to 12 months, with variable outcomes. Several required surgical debridement, as was the case with our patient. His PD catheter was removed and he was treated empirically with amikacin, azithromycin, and tigecycline intravenous induction. His ultimate long-term regimen was later switched to azithromycin, clofazimine, and tedizolid due to side effects and the eventually available susceptibility profile.ConclusionThe treatment of M. immunogenum remains a challenge due to the relative scarcity of data to guide treatment, and consequent lack of systemic approach to therapy. Most reported cases involve the use of a macrolide, often in combination with an aminoglycoside or a fluoroquinolone. Several started with intravenous induction, followed by transition to oral therapy on the order of weeks to months. Others also require surgical debridement. More data are required to develop a standardized approach to the treatment of M. immunogenum.Disclosures All authors: No reported disclosures.

A proteomics approach for the identification of species-specific immunogenic proteins in the Mycobacterium abscessus complex

The Mycobacterium abscessus complex can cause fatal pulmonary disease, especially in cystic fibrosis patients. Diagnosing M. abscessus complex pulmonary disease is challenging. Immunologic assays specific for M. abscessus are not available. In this study seven clinical M. abscessus complex strains and the M. abscessus reference strain ATCC19977 were used to find species-specific proteins for their use in immune assays. Six strains showed rough and smooth colony morphotypes simultaneously, two strains only showed rough mophotypes, resulting in 14 separate isolates. Clinical isolates were submitted to whole genome sequencing. Proteomic analysis was performed on bacterial lysates and culture supernatant of all 14 isolates. Species-specificity for M. abscessus complex was determined by a BLAST search for proteins present in all supernatants. Species-specific proteins underwent in silico B- and T-cell epitope prediction. All clinical strains were found to be M. abscessus ssp. abscessus. Mutations in MAB_4099c as a likely genetic basis of the rough morphotype were found in six out of seven clinical isolates. 79 proteins were present in every supernatant, of which 12 are exclusively encoded by all members of M. abscessus complex plus Mycobacterium immunogenum. In silico analyses predicted B- and T-cell epitopes in all of these 12 species-specific proteins.

Modeling and simulation of colonization of water-based metalworking fluid by Mycobacterium immunogenum

The water-borne human pathogen Mycobacterium immunogenum (MI) originating from industrial wastewater contaminated with metalworking fluid (MWF), may pose serious public health risks. This warrants a front-of-the-pipe approach so as to control its growth in these fluids; this requires an understanding of its initial colonization process in pristine MWF. In this direction, using a synthetic MWF formulation, quadratic modeling of colonization was performed using response surface methodology (RSM) to understand parameter effects and interactions followed by in-silico simulation of optimal and inhibitory growth conditions using Genetic Algorithm (GA), and experimental validation. The experimental parameters that supported optimal growth of MI in culture included an alkaline pH (9.4) coupled with ambient temperature (30 °C), starter nutrient (OADC 2.028% v/v) and tramp oil (0.4% v/v.) Though OADC seemed to play an important role, tramp oil was found to be crucial for the colonization process. However, combinations of higher pH and lower temperature (∼23 °C) and lower pH and high temperature (∼37 °C) completely arrested the growth even in the presence of OADC and tramp oil. Collectively, the results provide critical information needed for achieving simulated laboratory culture of this pathogen for further research; this may facilitate development of novel biocide-independent strategies to effectively control this pathogen and its disposal-related hazards in aqueous streams.

Effect of some plant growth-promoting rhizobacteria strains on root-knot nematode, Meloidogyne incognita, on tomatoes

Root-knot nematode, Meloidogyne incognita, is one of the main problems in vegetable-growing regions, decreasing yield quality and quantity worldwide. Root-knot nematode management tactics mostly involve chemical control which is a threat to the environment, consequences to human health. Biological control of nematodes is considered to be one of the best alternatives to the chemical control. In this study, the effect of some bacterial isolates against M. incognita was determined on tomato in the greenhouse. The trial was designed as a randomized complete block, consisting of 15 plant growth-promoting rhizobacteria (PGPR) strains and 2 control groups (−, +) with 10 replications, total of 170 pots. Two days after transplanting the bacteria-treated tomato (Solanum lycopersicum cv. 56-56 F1) seedlings in the sterile soil in pots, the plants were inoculated with 1000 eggs or J2s of M. incognita/pot. At the end of a 90-day plant-growing period, isolate ZHA90 of Bacillus pumilus decreased plant root galling which, in turn, increased plant height, shoot fresh and dry weight, and root fresh weight. Isolates ZHA296 and ZHA178 of Paenibacillus castaneae reduced the number of egg masses and root galling with no effects on plant growth compared to the control (+). While the isolate ZHA17 of Mycobacterium immunogenum increased plant height and shoot fresh weight, ZHA57 of the same bacterium enhanced significantly only plant height. Results indicated that among 15 bacterial strains studied, ZHA296 and ZHA178 of P. castaneae and ZHA17 and ZHA57 of M. immunogenum were identified as the promising biocontrol agents for the future nematode management tactics.

Persistent Cutaneous Infection Due to Mycobacterium Immunogenum, a Relatively Novel Species

Mycobacterium immunogenum is a species of nontuberculous mycobacteria (NTM) that has been recently identified as the cause of cutaneous infections.1-3 Historically, the majority of NTM infections were attributed to contamination of municipal water systems due to inadequate equipment sterilization. Many of these organisms have been found to grow in distilled water and display resistance to chlorine, formaldehyde, mercury, and standard disinfectants.4 In the environment, M. immunogenum has been isolated in swimming pools and adjacent showers.5 A limited number of cutaneous infections with Mycobacterium immunogenum have been reported, and an even smaller number of cases have been reported in immunocompetent individuals. We report a case of a persistent cutaneous infection with M. immunogenum in a previously healthy patient successfully treated with clarithromycin 250 mg twice daily for eight weeks. After treatment, the patient remained free of infection and only a minimal scar remained.

Comparative genomic analysis of Mycobacterium immunogenum strain CD11_6, a new potential vaccine strain against Mycobacterium tuberculosis

Comparative genomic analysis of Mycobacterium immunogenum strain CD11_6, a new potential vaccine strain against Mycobacterium tuberculosis

Early immunopathological events in acute model of mycobacterial hypersensitivity pneumonitis in mice

Prolonged exposure to antigens of non-tuberculous mycobacteria species colonizing industrial metalworking fluid (MWF), particularly Mycobacterium immunogenum (MI), has been implicated in chronic forms of hypersensitivity pneumonitis (HP) in machinists based on epidemiology studies and long-term exposure of mouse models. However, a role of short-term acute exposure to these antigens has not been described in the context of acute forms of HP. This study investigated short-term acute exposure of mice to MI cell lysate (or live cell suspension) via oropharyngeal aspiration. The results showed there was a dose- and time-dependent increase (peaking at 2 h post-instillation) in lung immunological responses in terms of the pro- (TNFα, IL-6, IL-1β) and anti-inflammatory (IL-10) cytokines. Bronchoalveolar lavage and histology showed neutrophils as the predominant infiltrating cell type, with lymphocytes <5% at all timepoints or concentrations. Granulomatous inflammation peaked between 8 and 24 h post-exposure, and resolved by 96 h. Live bacterial challenge, typically encountered in real-world exposures, showed no significant differences from bacterial lysate except for induction of appreciable levels of interferon (IFN)-γ, implying additional immunogenic potential. Collectively, the short-term mycobacterial challenge in mice led to a transient early immunopathologic response, with little adaptive immunity, which is consistent with events associated with human acute forms of HP. Screening of MWF-originated mycobacterial genotypes/variants (six of MI, four of M. chelonae, two of M. abscessus) showed both inter- and intra-species differences, with MI genotype MJY10 being the most immunogenic. In conclusion, this study characterized the first short-term mycobacterial exposure mouse model that mimics acute HP in machinists; this could serve as a potentially useful model for rapid screening of field MWF-associated mycobacteria for routine and timely occupational risk assessment and for investigating early biomarkers and mechanisms of this understudied immune lung disease.

Cutaneous infection due to Mycobacterium immunogenum: an European case report and review of the literature

(no more than 200 words): In the last few years, the incidence of cutaneous infections caused by nontuberculous mycobacteria is increasing. Since Mycobacterium immunogenum was first described in 2001, few case reports have been described, all of them in the American continent. We report a case with cutaneous infection caused by this newly discovered NTB in Europe.A 65-year-old woman presented with a 3-months history of pruritic lesions on abdomen. Examination revealed erythematous inflammatory papules, pustules, and crusts. Three weeks later, mycobacteria were cultured from the biopsy specimen. Mycobacterium immunogenum was identified based on susceptibility test results and polymerase chain reaction (PCR) restriction enzyme analysis. Treatment with clarithromycin was started. M. immunogenum is a nontuberculous mycobacterium that was first described by Wilson et al. in 2001 as a rapidly growing variety and new species in the Mycobacterium chelonae-Mycobacterium abscessus group. PCR-restriction analysis of a 439-bp segment of the hsp65 gene and/or sequencing the species-specific region of the 16S rDNA can confirm this new species. Since the description of M. immunogenum, 8 clinical case reports have been published, most involving cutaneous infections and all of them in the American continent. We present a case of cutaneous infection caused by M. immunogenum in a Spanish woman.

Fungal peptides from pneumonitis hypersensitivity etiologic agents are able to induce specific cellular immune response

PurposeHypersensitivity pneumonitis (HP) is an immunoallergic disease due to chronic exposure to high quantities of different microorganisms such as Mycobacterium immunogenum (Mi), a mycobacterium, and Lichtheimia corymbifera (Lc), a filamentous fungus. It has recently been demonstrated that the protein DLDH (dihydrolipoyl dehydrogenase), is common to these microorganisms. This study aimed to investigate the immune potential of overlapping peptide pools covering the MiDLDH and LcDLDH. Experimental designA selection of 34 peptides, from the MiDLDH and LcDLDH, able to interact with Major Histocompatibility Complex (MHC) 1 and MHC 2, was obtained using three different epitope prediction websites. By means of ELISPOT assays, we compared the frequency of Interferon gamma (IFNγ) secreting peripheral blood mononuclear cells (PBMC) after stimulation with overlapping peptide pools. Tests were performed using cells from 35 healthy blood donors. ResultsOne peptide pool containing five peptides from MiDLDH and able to interact with MHC 2 induced a marked IFNγ specific immune response (Pool F, p<0.001, Wilcoxon signed-rank test). ConclusionThis study demonstrated that peptides from microorganisms involved in HP were able to induce a high IFNγ specific immune response after stimulation of PBMCs from healthy blood donors which could be useful to develop an effective prevention strategy.

A rare case of non-tuberculous mastitis

A 15-year-old girl presented with left breast lump with purulent discharge. During the last three months she lost 4 kg weight. There was evening rise of temperature which was not associated with joint pains or chills. She had received three courses of antibiotics earlier in the other healthcare center, with no response. Ultrasound scan showed multiple cutaneous sinuses and FNA report findings were suggestive of chronic granulomatous mastitis. As the patient was not responding to multiple antibiotics courses, HRZE (Anti Tubercular Treatment, ATT) was started. But after three months of ATT she developed multiple sinus tracts filled with fluid and with superficial ulcerations, which was aspirated, sent for analysis and oral Moxifloxacin 400 mg was added. DNA based line probe assay detected Non Tuberculous mycobacterium (NTM) and was referred for NTM species identification. Molecular genetics assay identified Mycobacterium chelonae/ Mycobacterium immunogenum species and HRZE regimen was stopped. Patient was started on oral clarithromycin, linezolid according to sensitivity report. She responded well and repeat ultrasound scan showed significant resolution of the sinus and there was no discharge. NTM should be considered for breast infections that recur despite standard antibiotic therapy or ATT. Keywords: nontuberculous mastitis; anti tubercular therapy; antibiotics; young female