Phylogeographic Analysis of Mycobacterium kansasii Isolates from Patients with M. kansasii Lung Disease in Industrialized City, Taiwan.

Little is known about environmental transmission of Mycobacterium kansasii. We retrospectively investigated potential environmental acquisition, primarily water sources, of M. kansasii among 216 patients with pulmonary disease from an industrial city in Taiwan during 2015-2017. We analyzed sputum mycobacterial cultures using whole-genome sequencing and used hierarchical Bayesian spatial network methods to evaluate risk factors for genetic relatedness of M. kansasii strains. The mean age of participants was 67 years; 24.1% had previously had tuberculosis. We found that persons from districts served by 2 water purification plants were at higher risk of being infected with genetically related M. kansasii isolates. The adjusted odds ratios were 1.81 (1.25-2.60) for the Weng Park plant and 1.39 (1.12-1.71) for the Fongshan plant. Those findings unveiled the association between water purification plants and M. kansasii pulmonary disease, highlighting the need for further environmental investigations to evaluate the risk for M. kansasii transmission.

Efficacy and treatment outcome of infected patients with pulmonary Mycobacterium kansasii: A systematic review.

Background: Mycobacterium kansasii (M. kansasii) is a non-tuberculosis bacterium with a highly prevalent that is transferred by aerosols from water and soil resources to the respiratory system. M. kansasii is one of the main species responsible for NTM pulmonary disease. Methods: Web of Science, Scopus, and PubMed databases were systematically explored. Relevant articles from 1971 to November 2023 were reviewed. "The inclusion criteria" included patients with M. kansasii infection, treatment follow-up, and treatment outcomes. "The exclusion criteria" were clinical samples from animals, environmental samples, and other laboratory investigations. Results: 40 studies, including 1201 patients, were obtained through database search. Using the therapeutic regimens used in different studies, the therapy course for patients with M. kansasii infection ranged from 1 week to 118 months. In this study, the antibiotics prescribed in different treatment regimens for M. kansasii pulmonary infection were as follows: Rifampin, Ethambutol, Isoniazid, Clarithromycin, Streptomycin, and Pyrazinamide. Antibiotic combinations of three or four medicines, including rifampin, ethambutol, and isoniazid with or without streptomycin or pyrazinamide had the most therapeutic effect. Conclusion: The initial treatment involves rifampin, ethambutol, isoniazid, and pyridoxine, per the guidelines from the American Thoracic Society (ATS) and the Infectious Diseases Society of America (IDSA). Understanding the treatment plan and its outcomes is crucial for managing and determining the most effective therapy approach.

Phylogenomic and genomic analysis reveals unique and shared genetic signatures of Mycobacterium kansasii complex species.

Species belonging to the Mycobacterium kansasii complex (MKC) are frequently isolated from humans and the environment and can cause serious diseases. The most common MKC infections are caused by the species M. kansasii (sensu stricto), leading to tuberculosis-like disease. However, a broad spectrum of virulence, antimicrobial resistance and pathogenicity of these non-tuberculous mycobacteria (NTM) are observed across the MKC. Many genomic aspects of the MKC that relate to these broad phenotypes are not well elucidated. Here, we performed genomic analyses from a collection of 665 MKC strains, isolated from environmental, animal and human sources. We inferred the MKC pangenome, mobilome, resistome, virulome and defence systems and show that the MKC species harbours unique and shared genomic signatures. High frequency of presence of prophages and different types of defence systems were observed. We found that the M. kansasii species splits into four lineages, of which three are lowly represented and mainly in Brazil, while one lineage is dominant and globally spread. Moreover, we show that four sub-lineages of this most distributed M. kansasii lineage emerged during the twentieth century. Further analysis of the M. kansasii genomes revealed almost 300 regions of difference contributing to genomic diversity, as well as fixed mutations that may explain the M. kansasii's increased virulence and drug resistance.

Prevalence of Mycobacterium kansasii in clinical and environmental isolates, a systematic review and meta-analysis.

Background: Mycobacterium kansasii infection is one of the most common causes of non-tuberculosis mycobacterial (NTM) disease worldwide. However, accurate information on the global prevalence of this bacterium is lacking. Therefore, this study was conducted to investigate the prevalence of M. kansasii in clinical and environmental isolates. Methods: Databases, including PubMed, Scopus, and the Web of Science, were utilized to gather articles on the prevalence of M. kansasii in clinical and environmental isolates. The collected data were analyzed using Comprehensive Meta-Analysis software. Results: A total of 118 and 16 studies met the inclusion criteria and were used to analyze the prevalence of M. kansasii in clinical and environmental isolates, respectively. The prevalence of M. kansasii in NTM and environmental isolates were 9.4 and 5.8%, respectively. Subsequent analysis showed an increasing prevalence of M. kansasii over the years. Additionally, the results indicated a significant difference in the prevalence of this bacteria among different regions. Conclusion: The relatively high prevalence of M. kansasii among NTM isolates suggests the need for further implementation of infection control strategies. It is also important to establish appropriate diagnostic criteria and management guidelines for screening this microorganism in environmental samples in order to prevent its spread, given its high prevalence in environmental isolates.

Concomitantly Diagnosed Disseminated M kansasii Infection and Hairy Cell Leukemia With Review of Pathophysiology.

The association between Hairy Cell Leukemia (HCL) and non-tuberculous mycobacterial infections (NTMs) is well described, most notably Mycobacterium kansasii. The exact pathophysiology is not known. We report a case of a 31-year-old male with concomitantly diagnosed HCL and disseminated M kansasii infection who presented with rash, pancytopenia, and bulky axillary lymphadenopathy. The M kansasii was initially diagnosed through use of cell-free DNA detection and confirmed by bone marrow and lymph node cultures. Hairy Cell Leukemia was diagnosed with peripheral flow cytometry and confirmed via the same bone marrow sample. His HCL was put into remission with a single course of cladribine and rituximab chemotherapy; however, his M kansasii infection persisted for 6 months despite aggressive antimicrobial and surgical therapy. It was finally controlled using high-dose rifampin in combination with azithromycin and ethambutol. This case highlights the known link between HCL and M kansasii. Furthermore, it hints at potential causes beyond chemotherapy-induced immunocompromise. Notable possibilities include HCL cells acting as sanctuary sites for M kansasii to evade the immune system, and subclinical M kansasii infections causing NLRP3 inflammasome overactivation to trigger the oncogenic transformation to HCL. More research into the pathophysiologic link between HCL and M kansasii infections would allow for more effective prevention, diagnosis, and treatment of these severe atypical infections which are the major cause of morbidity in the cladribine era of HCL treatment.

Immunogenicity and vaccine potential of clinical isolate Mycobacterium kansasii strain against Mycobacterium tuberculosis infection.

Mycobacterium kansasii is a bacterium included in non-tuberculous mycobacteria (NTM) that can cause lung disease. It shares a significant number of antigens with Mycobacterium tuberculosis (Mtb), suggesting that it has the potential to be used as a tuberculosis (TB) vaccine. Therefore, we subcutaneously vaccinated mice with reference strain, M. kansasii-ATCC12478 [M. kansasii-American Type Culture Collection (ATCC)], and clinically isolated strain, M. kansasii-SM-1 to evaluate potential as a TB vaccine by comparing with bacille Calmette-Guerin (BCG) vaccine. Ten weeks after vaccination, we evaluated immunogenicity of M. kansasii-ATCC and M. kansasii-SM-1, and M. kansasii-SM-1 immunization induces potent Mtb antigen-specific IFN-γ-producing CD4+ T cells than M. kansasii-ATCC. Upon Mtb infection, M. kansasii-SM-1 provided better protection than M. kansasii-ATCC, which was comparable to the efficacy of BCG. These results showed that the clinical strain M. kansasii-SM-1, which exhibits an enhanced Mtb antigen-specific Th1 response, shows greater vaccine efficacy compared to M. kansasii-ATCC. In this study, we demonstrated that vaccine efficacy can vary depending on the strain of M. kansasii and that its efficacy can be comparable to BCG. This suggests that M. kansasii has the potential to be a live TB vaccine candidate.IMPORTANCEMycobacterium kansasii, a non-tuberculous mycobacteria (NTM) species causing lung disease, shares key antigens with Mycobacterium tuberculosis (Mtb), indicating its potential for TB vaccine development. Subcutaneous vaccination of mice with M. kansasii strains reference strain M. kansasii-ATCC12478 [(M. kansasii-American Type Culture Collection (ATCC)] and clinically isolated strain M. kansasii-SM-1 revealed differences in immunogenicity. M. kansasii-SM-1 induced a robust Mtb antigen-specific IFN-γ-producing CD4+ T cell response compared to M. kansasii-ATCC. Additionally, M. kansasii-SM-1 conferred better protection against Mtb infection than M. kansasii-ATCC, which is comparable to bacille Calmette-Guerin (BCG). These findings underscore the variable vaccine efficacy among M. kansasii strains, with M. kansasii-SM-1 exhibiting promising potential as a live TB vaccine candidate, suggesting its comparative effectiveness to BCG.

Disseminated Mycobacterium kansasii infection due to surgical site infection following allogeneic hematopoietic stem cell transplantation: A case report and literature review.

This report details a rare case of surgical site infection (SSI) caused by Mycobacterium kansasii following allogeneic hematopoietic stem cell transplantation (allo-HSCT) in a 53-year-old patient with IgA-κ type multiple myeloma. After undergoing multiple chemotherapy regimens and two stem cell transplants, the patient developed an SSI 31-month post-transplantation, manifesting as an intracranial abscess at the site of a previous craniotomy. M. kansasii was isolated from the drainage fluid, marking this instance as a unique case in the literature of nontuberculous mycobacteria (NTM) infection post-allo-HSCT with such a delayed onset. The patient's treatment included targeted antimicrobial therapy based on susceptibility testing, resulting in eventual resolution of the infection, although the patient later succumbed to multiple myeloma relapse. This case underscores the critical need to consider NTM infections in the differential diagnosis of persistent fevers and SSIs in immunocompromised patients, particularly those with chronic graft-versus-host disease. It highlights the importance of early diagnostic and therapeutic interventions to manage these infections effectively. This report contributes to the limited but growing body of literature on NTM infections post-allo-HSCT and emphasizes the need for vigilance in monitoring postoperative patients, especially those with prolonged immunosuppression.

Omadacycline drug susceptibility testing for non-tuberculous mycobacteria using oxyrase to overcome challenges with drug degradation.

BACKGROUND: Drug susceptibility testing (DST) protocol of omadacycline against non-tuberculous mycobacteria has not yet been established. We developed a method to accurately determine MIC omadacycline MIC against Mycobacterium abscessus (Mab), Mycobacterium avium-complex (MAC), and Mycobacterium kansasii (Mkn). METHODS: First, we identified the oxyrase concentration not affecting Mab, MAC, and Mkn growth followed by omadacycline MIC experiments with and without oxyrase using reference and clinical strains. RESULTS: Oxyrase 0.5 % (v/v) stabilized omadacycline in the culture medium. The median omadacycline MIC was 1 mg/L for Mab and 8 mg/L for Mkn. For MAC, the median omadacycline MIC was 2 mg/L for M. avium, 256 mg/L for M. intracellulare, and 4 mg/L for M. chimaera (p < 0.0001). Wilcoxon matched-pairs signed rank test revealed statistically lower MICs with oxyrase for all MAC subspecies (p < 0.0001), all Mab subspecies (p < 0.0001), and Mkn (p = 0.0002). The decrease in MICs with oxyrase was 17/18 of Mab, 14/19 of Mkn, 8/8 of M. avium, 4/5 M. chimera, but only 11/18 of M. intracellulare (p < 0.013). CONCLUSION: Use of 0.5 % oxyrase could be a potential solution to reliable and reproducible omadacycline MIC of Mab. However, oxyrase demonstrated a variable effect in reducing MICs against MAC and Mkn.

Differential radiological features of patients infected or colonised with slow-growing non-tuberculous mycobacteria.

Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is considered a growing health concern. The majority of NTM-PD cases in Europe are caused by slow-growing mycobacteria (SGM). However, distinct radiological features of different SGM remain largely uninvestigated. We applied a previously described radiological score to a patient cohort consisting of individuals with isolation of different SGM. Correlations between clinical data, species and computed tomography (CT) features were examined by logistic and linear regression analyses, as well as over the course of time. Overall, 135 pulmonary CT scans from 84 patients were included. The isolated NTM-species were mainly Mycobacterium avium complex (MAC, n = 49), as well as 35 patients with non-MAC-species. Patients with isolation of M. intracellulare had more extensive CT findings compared to all other SGM species (coefficient 3.53, 95% Cl - 0.37 to 7.52, p = 0.075) while patients meeting the ATS criteria and not undergoing therapy exhibited an increase in CT scores over time. This study provides insights into differential radiological features of slow-growing NTM. While M. intracellulare exhibited a tendency towards higher overall CT scores, the radiological features were similar across different SGM. The applied CT score might be a useful instrument for monitoring patients and could help to guide antimycobacterial therapy.

A Novel Inhibitor against the Biofilms of Non-Tuberculous Mycobacteria.

Non-tuberculous Mycobacteria (NTM), previously classified as environmental microbes, have emerged as opportunistic pathogens causing pulmonary infections in immunocompromised hosts. The formation of the biofilm empowers NTM pathogens to escape from the immune response and antibiotic action, leading to treatment failures. NF1001 is a novel thiopeptide antibiotic first-in-class compound with potent activity against planktonic/replicating and biofilm forms of various NTM species. It is potent against both drug-sensitive and -resistant NTM. It has demonstrated a concentration-dependent killing of replicating and intracellularly growing NTM, and has inhibited and reduced the viability of NTM in biofilms. Combination studies using standard-of-care (SoC) drugs for NTM exhibited synergetic/additive effects, but no antagonism against both planktonic and biofilm populations of Mycobacterium abscessus and Mycobacterium avium. In summary, the activity of NF1001 alone or in combination with SoC drugs projects NF1001 as a promising candidate for the treatment of difficult-to-treat NTM pulmonary diseases (NTM-PD) and cystic fibrosis (CF) in patients.

Identificación de la formación de cordones de Mycobacterium kansassi e implicancia en la microbiología clínica

Objetivos : Determinar si la formación de cordones ocurre en la microcolonias de M. kansasii. Material y métodos : Se sembraron en medio solido 7H11, cuatro especies de micobacterias patógenas de alta prevalencia Mycobacterium kansasii, Mycobacterium abscessus, Mycobacterium tuberculosis y Mycobacterium neonarum y se evaluaron hasta por 21 días, realizando complementariamente las coloraciones Ziehl-Neelsen para cada una de ellas. Para observar la presencia de la formación de cordones en las microcolonias, se utilizó microscopia de fase invertida. Resultados : En todas las especies se observó a nivel de las microcolonias la formación de cordones, además se identificó la formación de cordones en etapa temprana por la coloración Zhiel-Nelsen en Mycobacterium kansasii, Mycobacterium abscessus, y Mycobacterium tuberculosis. Conclusiones : Mycobacterium kansasii es capaz de desarrollar cordones a nivel microscópico, por lo que la premisa basada en la formación de cordones por M. tuberculosis como un patrón diferencial de las demás micobacterias deben ser tomadas con cautela.

SUMMARY Objectives : Determine if cord formation occurs in microcolonies of M. kansasii. Methods : 4 highly prevalent pathogenic mycobacterial species Mycobacterium kansasii, Mycobacterium abscessus, Mycobacterium tuberculosis and Mycobacterium neonarum were sown in 7H11 solid medium and observed for up to 21 days, additionally Ziehl-Neelsen staining was performed for each of them. Additionally, Ziehl-Neelsen staining was performed for each of them, observing the presence of cord formation in the microcolonies and determining their relationship with virulence and specific species Results : In all the species cultivated in solid medium 7H11, the formation of cords was observed at the level of the microcolones, in addition, the formation of cords in an early stage was identified by the Zhiel-Nelsen staining in Mycobacterium kansasii, Mycobacterium abscessus, and Mycobacterium tuberculosis. Conclusions : Mycobacterium kansasii is capable of developing beads at the microscopic level as was observed in microcoloneas, so the premise based on beads by microscopy specific for the M. tuberculosis species as a differential pattern from the other mycobacteria by forming beads in cultures must be taken with caution so as not to generate a misdiagnosis since there are other species that are capable of forming a similar pattern as has been observed in Mycobacterium kansasii.

Clinical and epidemiological characteristics of M. kansasii pulmonary infections from Rio de Janeiro, Brazil, between 2006 and 2016 / Características clínicas e epidemiológicas de casos de infecção pulmonar por Mycobacterium kansasii no Rio de Janeiro, no período de 2006 a 2016

Objetivo: Avaliar características clínicas, tomográficas e microbiológicas dos pacientes com doença pulmonar causada pela M. kansasii (DPMK) atendidos em unidade ambulatorial no período 2006-2016. Métodos: Estudo descritivo, em que foram analisados 38 pacientes. Foram analisadas as características demográficas, clínico-radiológicas, laboratoriais e terapêuticas. Resultados: A média de idade foi 64 anos (DP=10,6; IIQ=57-72; mediana=65,0) e 22 (57,9%) eram pacientes do sexo masculino. Comorbidade pulmonar estava presente em 89,5%. A comorbidade mais frequente foi a bronquiectasia (78,9%). Tratamento anterior para tuberculose pulmonar (TBP) foi relatado em 65,9%. O esquema terapêutico mais utilizado foi rifampicina, isoniazida e etambutol (44,7%). A tomografia de tórax (TCT) mostrou bronquiectasia (94,1%), distorção arquitetural (76,5%), espessamento de septo (67,6%) e cavidades (64,7%). A doença foi bilateral em 85,2%. Houve 10,7% de resistência à rifampicina, 67,9% resistentes ao etambutol e sensibilidade à claritromicina. Conclusão: Em pacientes com doença pulmonar estrutural, é importante a busca de DPMNT, principal diagnóstico diferencial com TBP. TC de tórax demonstra diferentes padrões que se sobrepõem ao de doença estrutural causada por TBP ou outras enfermidades pulmonares. Destaca-se a resistência ao etambutol, fármaco componente do esquema preconizado.

Características clínicas e epidemiológicas de casos de infecção pulmonar por Mycobacterium kansasii no Rio de Janeiro, no período de 2006 a 2016 / Clinical and epidemiological characteristics of M. kansasii pulmonary infections from Rio de Janeiro, Brazil, between 2006 and 2016

RESUMO Objetivo Avaliar características clínicas, tomográficas e microbiológicas dos pacientes com doença pulmonar causada pela M. kansasii (DPMK) atendidos em unidade ambulatorial no período 2006-2016. Métodos Estudo descritivo, em que foram analisados 38 pacientes. Foram analisadas as características demográficas, clínico-radiológicas, laboratoriais e terapêuticas. Resultados A média de idade foi 64 anos (DP=10,6; IIQ=57-72; mediana=65,0) e 22 (57,9%) eram pacientes do sexo masculino. Comorbidade pulmonar estava presente em 89,5%. A comorbidade mais frequente foi a bronquiectasia (78,9%). Tratamento anterior para tuberculose pulmonar (TBP) foi relatado em 65,9%. O esquema terapêutico mais utilizado foi rifampicina, isoniazida e etambutol (44,7%). A tomografia de tórax (TCT) mostrou bronquiectasia (94,1%), distorção arquitetural (76,5%), espessamento de septo (67,6%) e cavidades (64,7%). A doença foi bilateral em 85,2%. Houve 10,7% de resistência à rifampicina, 67,9% resistentes ao etambutol e sensibilidade à claritromicina. Conclusão Em pacientes com doença pulmonar estrutural, é importante a busca de DPMNT, principal diagnóstico diferencial com TBP. TC de tórax demonstra diferentes padrões que se sobrepõem ao de doença estrutural causada por TBP ou outras enfermidades pulmonares. Destaca-se a resistência ao etambutol, fármaco componente do esquema preconizado.

ABSTRACT Objective To evaluate clinical, tomographic, and microbiological characteristics of pulmonary disease caused by M. kansasii (MKPD) in patients treated at an outpatient unit from 2006-2016. Methods We studied thirty eight patients, and analyzed socio-demographic, clinical-radiological, laboratory, and therapeutic characteristics. Results The mean age was 64 years (SD = 10.6; IIQ = 57-72; median = 65.0), and 22 (57.9%) male patients. Pulmonary comorbidity was present in 89.5% of the patients. The most frequent comorbidity was bronchiectasis (78.9%). Previous treatment for pulmonary tuberculosis (PTB) was found in 65.9%. The most used therapeutic regimen was rifampicin, isoniazid and ethambutol (44.7%). Chest tomography (CT) showed bronchiectasis (94.1%), architectural distortion (76.5%), septum thickening (67.6%), and cavities (64.7%). Disease was bilateral in 85.2%. We observed 10.7% resistance to rifampicin, 67.9% resistance to ethambutol, and sensitivity to clarithromycin. Conclusion In patients with structural lung disease, it is important to search for NTM, the main differential diagnosis with PTB. Chest CT showed different patterns that overlapped with structural disease caused by PTB or other lung diseases. We observed resistance to ethambutol, a drug component of the recommended regimen.

Chemical composition and in vitro antibacterial activity of essential oils from Murraya paniculata (L. ) Jack (Rutaceae) ripe and unripe fruits against bacterial genera Mycobacterium and Streptococcus

This study aims to investigate chemical composition of essential oils from Murraya paniculata (L.) Jack (Rutaceae) ripe and unripe fruits and determine their in vitro antibacterial activity. Essential oils were extracted by hydrodistillation from Murraya paniculata (L.) Jack ripe and unripe fruits collected in the Cerrado, in Rio Verde, southwestern Goiás, Brazil. They were analyzed by gas chromatography with flame ionization detector (GC-FID) and by gas chromatography-mass spectrometry (GC-MS). Sesquiterpenes, which represent the most abundant class of compounds in oils, predominated in both ripe and unripe fruits. Major constituents of essential oils extracted from ripe fruits (RF-EO) were (-caryophyllene (21.3%), (-ylangene (13.3%), germacrene-D (10.9%) and (-zingiberene (9.7%) whereas the ones of unripe fruits (UF-EO) were sesquithujene (25.0%), (-zingiberene (18.2%), germacrene-D (13.1%) and (-copaene (12.7%). In vitro antibacterial activity of essential oils was evaluated in terms of its minimum inhibitory concentration (MIC) values by the broth microdilution method in 96-well microplates. Both essential oils under investigation showed moderate anti-streptococcal activity against the following bacteria: Streptococcus mutans, S. mitis, S. sanguinis, S. sobrinus and S. salivarius. MIC values ranged between 100 and 400 µg/mL. Regarding the antimycobacterial activity, essential oils from M. paniculata (L.) Jack unripe and ripe fruits were active against Mycobacterium kansasii (MIC = 250 µg/mL), moderately active against M. tuberculosis (MIC = 500 µg/mL) and inactive against M. avium (MIC = 2000 µg/mL). This study was pioneer in revealing similar chemical profiles of both essential oils extracted from Murraya paniculata (L.) Jack unripe and ripe fruits, besides describing their in vitro anti-streptococcal and antimycobacterial activities.

Whole genome sequence of Mycobacterium kansasii isolates of the genotype 1 from Brazilian patients with pulmonary disease demonstrates considerable heterogeneity

Mycobacterium kansasii is an opportunistic pathogen and one of the most commonly encountered species in individuals with lung disease. We here report the complete genome sequence of 12 clinical isolates of M. kansasii from patients with pulmonary disease in Brazil.

Micobacteriosis pulmonar por Mycobacterium kansasii / Micobacteriosis pulmonar por Mycobacterium kansasii

Micobacterias no tuberculosas (MNT) es una designación utilizada para referirse a un gran número de especies de micobacterias ambientales potencialmente patógenas y no patógenas, distintas de la Mycobacterium tuberculosis y Mycobacterium leprae. Mycobacterium kansasii (M. Kansasii) es una MNT oportunista causante de infecciones pulmonares, cutáneas, entre otras, cuya tasa de incidencia ha ido incrementando en los últimos años a nivel mundial. A través de presentar el siguiente caso se pretende aportar al conocimiento con respecto al abordaje de pacientes con infección por MNT a nivel pulmonar, dirigido a médicos que trabajan en atención primaria de salud (APS). Se trata del caso de una paciente de 46 años de edad que acude al Hospital Provincial General Docente de Riobamba (HPGDR) con infección por MNT a nivel pulmonar. En el examen microscópico se detectaron Bacilos­Ácido­Alcohol­Resistentes (BAAR) mientras en el cultivo de esputo más antibiograma se aisló M. kansasii resistente a los antibióticos utilizados para la terapia convencional de tuberculosis. Se trata de un caso raro en la práctica clínica. Es crucial saber cómo manejar una infección con M. kansasii debido a su implicación para la salud del paciente y el sistema de salud nacional. El médico de APS debe reconocer su papel fundamental y la importancia que tiene un diagnóstico oportuno y tratamiento adecuado.

Non­tuberculous mycobacteria (NTM) is a designation for a large number of mycobacterial species potentially pathogenous and non­pathogenous, different than Mycobacterium tuberculosis and Mycobacterium leprae. Mycobacterium kansasii (M. kansasii) is an opportunistic NTM that causes among other things, pulmonary and cutaneous infections, whose incidence is increasing worldwide. Trough the following case report we seek to provide a guide to physicians working on primary health care (PHC) on the management of patients with pulmonary infection caused by NTM. We report the case of a 46­year­old female patient who came to the Hospital Provincial General Docente de Riobamba (HPGDR) with a pulmonary infection caused by NTM. In the microscopic examination it was identified Acid­Fast Bacilli (AFB), meanwhile the microbiological culture and antibiogram it was isolated M. kansasii resistant to common antibiotics used for conventional tuberculosis therapy. It is a rare case in the clinical practice. It is crucial to know how to manage an infection with M. Kansasii due to its implication on the health of affected subjects and the national health system. A physician working on PHC has to know his/her fundamental role and the importance of an early diagnosis and adequate treatment.

Micobacterias atípicas en cinco pacientes adultos sin evidencias de inmunosupresión: Construyendo una experiencia / Atypical mycobacterial infections in five adult patients without evidence of immunosuppression: Making an experience

We aim to communicate the experience gathered during the management of infections by atypical mycobacteria in immunocompetent patients in a general practice. Between 2008 and 2013, 5 patients with non-tuberculous mycobacterial infections were identified: 2 with cutaneous involvement and 3 with lung infection. None of them had evidence of immunosuppression. A patient with elbow bursitis by M. chelonae presented with a high mononuclear count in fluid analysis with mycobacterial growth at the fifth day of culture. He evolved satisfactorily with clarithromycin. A case with M. fortuitum skin infection had a delayed initial diagnosis with progression to local draining lymph nodes; the culture when requested was positive after 13 days of incubation. Patients with pulmonary infection presented with prolonged cough and sputum and had in common to be postmenopausal women displaying small nodules and bronchiectases at lung images, a classical pattern. Time elapsed between respiratory sampling and a definitive inform ranged from 40 to 89 days. Non-tuberculous mycobacterial infections in non-immunosuppresed patients can generate diagnostic and therapeutic challenges. Delay in identification contributes to this problem.

El objetivo de este trabajo es reportar la experiencia acumulada sobre infecciones por micobacterias atípicas en pacientes sin inmunosupresión. Entre el año 2008 y 2013 se observaron cinco pacientes con infección por micobacterias atípicas: dos con infección cutánea y tres con infección pulmonar. Ninguno de estos pacientes tenía evidencias de inmunosupresión. Un paciente con bursitis de codo por M. chelonae tuvo un estudio citoquímico con aumento de celularidad de predominio mononuclear y desarrollo de bacterias al quinto día; respondió favorablemente a claritromicina. Un caso con infección cutánea por M. fortuitum evolucionó en forma prolongada con supuración ganglionar antes del diagnóstico y el cultivo solicitado a los 13 días fue positivo. Los tres pacientes con aislados pulmonares presentaron tos y expectoración y tenían en común ser mujeres en edad post-menopáusica y presentar pequeños infiltrados nodulares asociados a bronquiectasias en el estudio de imágenes pulmonares, un patrón descrito en la literatura científica. En estos tres casos, la latencia entre la toma de muestra y el informe definitivo tuvo un rango de 40 a 89 días. El aislamiento de micobacterias atípicas en muestras de expectoración en pacientes sin inmunosupresión se da en un contexto típico pero plantea dificultades diagnósticas y terapéuticas. El lento crecimiento de estos microorganismos en el laboratorio contribuye a este problema.

Abscess resulting from Mycobacterium kansasii in the left thigh of AIDS patient

A case of abscess resulting from Mycobacterium kansasii, in the left thigh of a 53-year-old woman infected with the Human Immunodeficiency virus, is reported. Curiously, there was no pulmonary or systemic involvement as is usual with these Mycobacterium infections. The patient had CD4 T lymphocyte count of 257 cells/µL and a viral load of 60,154 copies. Despite presenting a relatively preserved immunity, the patient also presented Criptococcic meningoencephalitis and Esophageal candidiasis. The patient responded satisfactorily to treatment for infections and after 51 days was discharged.