In this study we describe the first isolation of Mycobacterium triplex in Latin America. This species causes infections in humans, with very few reports from around the world. We isolated two sputum specimens of a patient with a 6-year history of human immunodeficiency and tuberculosis treatment failure. All tests used confirmed M. triplex and the patient responded well to drug therapy for 18 months.

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Background: Antituberculosis drugs cause hepatotoxicity in some individuals leading to acute liver failure, which results in death. Such phenomena limit the clinical use of drugs, contributing to treatment failure that possibly causes drug resistance. Furthermore, associated risk factors for the development of antituberculosis-drug-induced hepatotoxicity (anti-TB-DIH) are found to be controversial among different study findings. Methods: A prospective cohort study was conducted from May 2014 to October 2014 in Dawro Zone, Tercha District Hospital Laboratory, South Ethiopia. One hundred and twenty-four new tuberculosis-positive individuals available from Tercha Hospital and five health centers during data collection were consecutively included. The sociodemographic data and anthropometric measurement were obtained. Then, 5 mL of venous blood was drawn from each individual, and the alanine transaminase, aspartate transaminase, and total bilirubin were measured photometrically at baseline, and then continuously monitored by measuring these liver enzymes every 2 weeks for 2 months. Data were analyzed with SPSS version 20 for Windows (SPSS Inc., Chicago, IL, USA). Results: The incidence of anti-TB-DIH was found to be 8% (10 patients out of 124). Raised serum transaminase and bilirubin level, as well as signs and symptoms of hepatotoxicity (nausea, anorexia, vomiting, malaise, and jaundice), were observed in the cases. The onset of hepatotoxicity ranged from 13 days to 58 days (median, 26 days) after treatment was initiated. Of the various risk factors analyzed, only high alcohol intake was associated with the incidence of anti-TB-DIH (odds ratio=9.3, 95% confidence interval 1.8–47, p <.007). Age, gender, extent of tuberculosis disease, and malnutrition were not significantly associated with anti-TB-DIH. Conclusion: The incidence of anti-TB-DIH in Dawro Zone was high. The drug responsible for the hepatotoxicity was not known. However, chronic high alcohol intake was associated with the development of anti-TB-DIH.

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Objective/background: The in vitro drug-susceptibility testing of Mycobacterium tuberculosis reports isolates as resistant or susceptible on the basis of single critical concentrations. It is evident that drug resistance in M. tuberculosis is quite heterogeneous, and involves low level, moderate level, and high level of drug-resistant phenotypes. Thus, the aim of our study was to correlate rrs (X52917) and eis (AF144099) promoter mutations, found in M. tuberculosis isolates, with corresponding minimum inhibitory concentrations of amikacin, kanamycin, and capreomycin. Methods: Ninety M. tuberculosis clinical isolates were analyzed in this study. The minimum inhibitory concentrations were determined by MGIT 960 for 59 isolates with resistance-associated mutations in the rrs and eis promoter gene regions, and 31 isolates with wild-type sequences, as determined by the GenoType MTBDRsl (version 1) assay. Results: The rrs A1401G mutation was identified in 48 isolates resistant to the second-line injectables. The eis promoter mutations C-14T (n=3), G-10C (n=3), G-10A (n=3), and C-12T (n=2) were found within 11 isolates with various resistance profiles to the second-line injectables. Thirty-one isolates had wild-type sequences for the rrs and eis promoter gene regions of interest, one of which was amikacin, kanamycin, and capreomycin resistant. The isolates with the rrs A1401G mutation had amikacin, kanamycin, and capreomycin minimum inhibitory concentrations of >40 mg/L, >20 mg/L, and 5–15 mg/L, respectively. The isolates with eis promoter mutations had amikacin, kanamycin, and capreomycin minimum inhibitory concentrations of 0.25–1.0 mg/L, 0.625–10 mg/L, and 0.625–2.5 mg/L, respectively. Conclusion: This study provides a preliminary basis for the prediction of phenotypic-resistance levels to the second-line injectables based upon the presence of genetic mutations associated with amikacin, kanamycin, and capreomycin resistance. The results suggest that isolates with eis promoter mutations have consistently lower resistance levels to amikacin, kanamycin, and capreomycin than isolates with the rrs A1401G mutation.

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Objective/background: There is an urgent need for a more effective vaccine against Mycobacterium tuberculosis (Mtb). Although CD4+ T cells play a central role in host immunity to Mtb, recent evidence suggests a critical role of CD8+ T cells in combating Mtb. In the present study, we have predicted HLA antigen class I binding peptides of DosR operon using an in-silico approach. This method is useful as an initial computational filtration of probable epitopes based on their binding ability and antigenicity. Methods: CD8+ epitopes were predicted by software NetMHC 3.4 and BIMAS. Self-peptides were found and excluded by indigenously developed Perl script. Antigenicity of promiscuous peptides was predicted using a VaxiJen server. The top VaxiJen scoring antigenic peptides were docked to globally relevant HLA allele using CABS dock and Hex program. Results: A total of 1436 overlapping nonamer peptides were generated which gave 46 promiscuous epitopes, 25 were predicted to be antigenic. Rv2627 epitope “SAFRPPLV” which gave the highest Vaxijen score of 1.9157 and showed binding to all the three HLA loci. The top VaxiJen scoring antigenic peptides were docked and had significant interactions with residues of the HLA class I molecule indicating them to be good cytotoxic T lymphocyte epitopes. Conclusion: Our study has generated several promiscuous antigenic peptides capable of binding to major histocompatibility complex class I with high affinity. These epitopes can become part of a postexposure multivalent subunit vaccine upon experimental validation.

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Background: Tuberculosis (TB) could be fatal if left untreated, however, adverse effects of anti-TB medications (anti-TBs) themselves may limit treatment. We determined the incidence and clinical characteristics of hepatotoxicity in hospitalized patients receiving first-line anti-TB treatment. Methods: A retrospective cohort study of patients aged ≥18 years seen at the medical wards of the Jos University Teaching Hospital from January 2013 to June 2013 was carried out. Data were retrieved for 110 patients who were prescribed anti-TBs. Their demographic and clinical characteristics were described, and the incidence of symptomatic hepatotoxicity determined. The incidence of hepatotoxicity by strict American Thoracic Society criteria (symptomatic hepatotoxicity plus alanine transaminase in IU/L levels >3×upper limit of normal) was also determined. Results: Twenty patients developed symptomatic hepatotoxicity, giving an incidence of 18.2%. Furthermore, 18 (16.4%) patients had hepatotoxicity according to the American Thoracic Society criteria. Those with symptomatic hepatotoxicity unexpectedly had lower baseline alanine transaminase interquartile range (IQR) (35 [16–63] vs. 67 [4–226]; p =.04) and bilirubin (μmol/L): total IQR (15.3 [10.2–74.8] vs. 20.4 [20.4–20.4]; p =.01) and conjugated IQR (7.6 [5.1–34.8] vs. 10.2 [10.2–10.2]; p =.004). However, there were no significant differences in age, sex, body mass index, and duration of anti-TB treatment, human immunodeficiency virus infection status, antiretroviral therapy status, alcohol consumption, and the presence of hepatitis B surface antigen or hepatitis C virus antibody. Conclusion: Hepatotoxicity due to first-line anti-TBs, whether based on clinical features alone or backed by liver chemistry, is common among hospitalized patients in our environment. Studies to determine the predictors of hepatotoxicity to guide clinical interventions aimed at the prevention or timely identification of cases are needed.

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The number of multidrug-resistant tuberculosis patients is increasing each year in many countries all around the globe. Malaysia has no exception in facing this burdensome health problem. We aimed to investigate the factors that contribute to the occurrence of multidrug-resistant tuberculosis among Malaysian tuberculosis patients. An unmatched case-control study was conducted among tuberculosis patients who received antituberculosis treatments from April 2013 until April 2014. Cases are those diagnosed as pulmonary tuberculosis patients clinically, radiologically, and/or bacteriologically, and who were confirmed to be resistant to both isoniazid and rifampicin through drug-sensitivity testing. On the other hand, pulmonary tuberculosis patients who were sensitive to all first-line antituberculosis drugs and were treated during the same time period served as controls. A total of 150 tuberculosis patients were studied, of which the susceptible cases were 120. Factors found to be significantly associated with the occurrence of multidrug-resistant tuberculosis are being Indian or Chinese (odds ratio 3.17, 95% confidence interval 1.04–9.68; and odds ratio 6.23, 95% confidence interval 2.24–17.35, respectively), unmarried (odds ratio 2.58, 95% confidence interval 1.09–6.09), living in suburban areas (odds ratio 2.58, 95% confidence interval 1.08–6.19), are noncompliant (odds ratio 4.50, 95% confidence interval 1.71–11.82), were treated previously (odds ratio 8.91, 95% confidence interval 3.66–21.67), and showed positive sputum smears at the 2nd (odds ratio 7.00, 95% confidence interval 2.46–19.89) and 6th months of treatment (odds ratio 17.96, 95% confidence interval 3.51–91.99). Living in suburban areas, positive sputum smears in the 2nd month of treatment, and was treated previously are factors that independently contribute to the occurrence of multidrug-resistant tuberculosis. Those with positive smears in the second month of treatment, have a history of previous treatment, and live in suburban areas are found to have a higher probability of becoming multidrug resistant. The results presented here may facilitate improvements in the screening and detection process of drug-resistant patients in Malaysia in the future.

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Objective/background: The search for new vaccines more efficacious than bacille Calmette–Guérin for tuberculosis prevention is of paramount importance for the control of the disease. The expression of Mycobacterium tuberculosis antigens in Mycobacterium smegmatis is one of the current strategies for the development of new-generation vaccines against tuberculosis. The objective of this study was to evaluate the immunogenicity in mice of M. smegmatis expressing epitopes from Ag85B antigen. Methods: M. smegmatis expressing three T cell epitopes from M. tuberculosis Ag85B (P21, P26, and P53) was constructed (rMs064). rMs064 was used to immunize BALB/C mice for immunogenicity evaluation. The present study investigates the capacity of rMs064 to induce specific cellular and humoral immune responses against the expressed epitopes. Cytokine production upon stimulation with Ag85B peptides and specific total immunoglobulin G and immunoglobulin G subclasses were determined. Results: The results showed a significant production of interleukin-12 and interleukin-23 when splenocytes were stimulated with P21, P26, and P53 peptides, and interferon-γ after stimulation with P21 in animals immunized with rMs064 compared with controls. The total immunoglobulin G and its subclasses showed significant increases against the Ag85B epitopes in the sera of rMs064-immunized mice compared with the control groups. Conclusion: The results of this study support the future evaluation of rMs064 as a vaccine candidate against tuberculosis in challenge experiments.

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Objective/Background: Tuberculosis (TB) is a major cause of morbidity and mortality in developing countries. Passive case detection in national TB programmes is associated with low case notification, especially in children. This study was undertaken to improve detection of childhood TB in resource-poor settings through intensified case-finding strategies. Methods: A community-based intervention was carried out in six states in Nigeria. The creation of TB awareness was undertaken, and work aids, guidelines, and diagnostic charts were produced, distributed, and used. Various cadres of health workers and ad hoc project staff were trained. Child contacts with TB patients were screened in their homes, and children presenting at various hospital units were screened for TB. Baseline and intervention data were collected for evaluation populations and control populations. Results: Detection of childhood TB increased in the evaluation population during the intervention, with a mean quarterly increase of 4.0% [new smear positive (NSP), although the increasing trend was not statistically significant (χ²=1.8; p <.179)]. Additionally, there was a mean quarterly increase of 3% for all forms of TB, although the trend was not statistically significant (χ²=1.48; p <.224). Conversely, there was a decrease in case notification in the control population, with a mean decline of 3% (all forms). Compared to the baseline, there was an increase of 31% (all forms) and 22% (NSP) in the evaluation population. Conclusion: Intensified case finding combined with capacity building, provision of work aids/guidelines, and TB health education can improve childhood-TB notification.

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In this study, we analyzed Mycobacterium tuberculosis complex (MTC) genetic diversity in Anambra State, Nigeria based on spoligotyping followed by 5-loci exact tandem repeats (ETRs). Spoligotyping of 180 MTC strains isolated in 2009–2011 from pulmonary tuberculosis (TB) patients led to a total of 31 distinct patterns. A comparison with the SITVIT2 international database showed that all the 31 patterns could be classified as Shared-types (SITs) in this database; briefly, 26/31 SITs (n =174 isolates) matched a preexisting shared-type in the database, whereas 5/31 SITs (n =6 isolates) were newly created due to 2 or more strains belonging to an identical new pattern within this study (SIT3396) or after a match with an orphan in the database (SIT3397, SIT3398, SIT3399 and SIT3400). A total of 18/31 SITs containing 167 or 92.8% isolates were clustered within this study (2–89 isolates per cluster) while 13/31 SITs contained unique strains. Using VNTR typing, a total of 36 distinct patterns were identified; 27 patterns (n =157 isolates) matched a pattern already reported in the SITVIT2 database. Combination of both the methods generated 47 combined patterns for the 180 strains: 17 belonged to clustered isolates (n =127 isolates or 70.5%) while 30 corresponded to as many unique strains (note 23 strains could not be typed using 5-loci ETRs). No correlation was found between the spoligotyping pattern and the HIV status of the patient or drug sensitivity of the strain. This study showed that the LAM10-CAM prototype SIT61 accounted for highest number of isolates (n =89) in Anambra State, showing its relative contribution to the TB burden in the study.

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It is estimated that about 40% of the Indian population are infected with tuberculosis (TB) and that ~3,000,000 people die as a result of TB annually. TB is caused by Mycobacterium tuberculosis. In 2011, the World Health Organization declared India as having the highest TB burden worldwide. An important criteria for pathogenicity is the presence of mycolic acid linked to the protective outer membrane of bacteria. Mycolyl transferase catalyzes the transfer of mycolic acid and promotes cell wall synthesis. This is also considered as a novel target for drug-mediated intervention strategies. Here, we have attempted to understand the interaction between the antimicrobial peptide (AMP), dermcidin, and mycolyl transferase in M. tuberculosis using a computational approach. The present study was undertaken in order to elucidate the capability of AMPs to treat this bacteria, which is less sensitive to available antibiotics, and to design a novel method for new therapies.

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Pulmonary tuberculosis (TB) is the most common form of TB. Primary infection can also affect the pharynx, cervical lymph node, intestine, or oral mucosa. Historically, the observed incidence of concomitant infection with leprosy and TB is high. However, reports of concomitant infection in modern literature remain scarce. Most cases reported in the literature had borderline/lepromatous leprosy and pulmonary tuberculosis. Extrapulmonary tuberculosis is reported in only 3.2% of leprosy cases. To the best of our knowledge, this is the first case report of primary oral tuberculosis of the tongue in a patient with lepromatous leprosy with Type 2 lepra reaction. The patient was referred to Directly Observed Treatment, Short-Course clinic and started on Category I treatment. She received oral prednisolone for lepra reaction, which was subsequently tapered and stopped, however, she continued to receive other antileprotic drugs (thalidomide and clofazimine). The patient's general condition improved and she is on regular follow up.

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Tuberculosis and lung cancer rarely coincide together but have been proven to have a definitive link. In this case we describe tuberculosis and adenocarcinoma diagnosed together in the same lobe of the lung. The patient was found to have an epidermal growth factor receptor exon 19 deletion, which has been shown to have an association with tuberculosis.

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During its persistence in the infected host, Mycobacterium tuberculosis (Mtb) accumulates host-derived fatty acids in intracytoplasmic lipid inclusions as triacylglycerols which serve primarily as carbon and energy reserves. The Mtb genome codes for more than 15 triacylglycerol synthases, 24 lipase/esterases, and seven cutinase-like proteins. Hence, we looked at the expression of the corresponding genes in intracellular bacilli persisting amidst the host triacylglycerols. We used the Mtb infected murine adipocyte model to ensure persistence and transcripts were quantified using real-time reverse transcriptase polymerase chain reaction. Dormancy and glyoxylate metabolism was confirmed by the upregulated expression of dosR and icl, respectively, by intra-adipocyte bacilli compared with in vitro growing bacilli. The study revealed that tgs1, tgs2, Rv3371, and mycolyltransferase Ag85A are the predominant triacylglycerol synthases, while lipF, lipH, lipJ, lipK, lipN, lipV, lipX, lipY, culp5, culp7, and culp6 are the predominant lipases/esterases used by Mtb for the storage and degradation of host-derived fat. Moreover, it was observed that many of these enzymes are used by Mtb during active replication rather than during nonreplicating persistence, indicating their probable function in cell wall synthesis.

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Objective/Background: The diagnostics of latent tuberculosis infection in Poland using the tuberculin skin test is challenging due to the obligatory Bacillus Calmette–Guérin vaccinations. Interferon-gamma release assays are still very rarely used for diagnostics. We compared the tuberculin skin test and the QuantiFERON-TB Gold In-Tube test to evaluate the degree of latent tuberculosis infection in at-risk groups for tuberculosis (homeless, close contacts, periodic contacts, nursing-home attendees) and in healthy individuals. Methods: QuantiFERON-TB Gold In-Tube tests were carried out on 785 individuals from the homeless (n=150), close contacts (n=171), periodic contacts (n=163), nursing-home attendees (n=152), and healthy individuals (n=149). The tuberculin skin test was performed on 129, 156, 147, 148, and 121 participants, respectively. We evaluated the (a) correlation between serum concentrations of interferon gamma and the tuberculin-skin-test induration diameter; (b) between the number of QuantiFERON-TB Gold In-Tube-positive results and the tuberculin-skin-test diameter in the studied groups; and (c) agreement between both tests and the kappa coefficient using the tuberculin-skin-test diameters of 5, 10, and 15 mm. Results: Larger tuberculin-skin-test induration diameters were associated with elevated serum concentrations of interferon gamma. We found a positive correlation between the number of positive QuantiFERON-TB Gold In-Tube screening results and the tuberculin-skin-test induration diameter. The agreement between QuantiFERON-TB Gold In-Tube and tuberculin-skin-test screening results improved with increasing tuberculin-skin-test induration diameter. Conclusion: Based on measures of tuberculin-skin-test induration diameter alone, it is difficult to diagnose latent tuberculosis infection with certainty. The agreement of the QuantiFERON-TB Gold In-Tube test increases with the tuberculin-skin-test diameter. Tuberculin-skin-test diameters larger than 15 mm are more likely to be associated with active infection.

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Selective immunoglobulin M (SIgM) deficiency is a rare form of dysgammaglobulinemia. Here we are reporting a 31 year old man with multiple cervical and testicular abscesses who was investigated and found to have miliary tuberculosis (MTB) with primary SIgM deficiency (Serum IgM: 17.4 mg/dL) and was treated aggressively with anti-tuberculous treatment.

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Objective/Background: Mycobacterium tuberculosis (MTB) causes active tuberculosis (TB) in only a small percentage of infected people. In most cases, the infection is clinically latent, where bacilli can persist in human hosts for years without causing disease. Surprisingly, the biology of such persister cells is largely unknown. This study describes the isolation, identification, and whole-genome sequencing (WGS) of latent TB bacilli after 782 days (26 months) of latency (the ability of MTB bacilli to lie persistent). Methods: The in vitro double-stress model of latency (oxygen and nutrition) was designed for MTB culture. After 26 months of latency, MTB cells that persisted were isolated and investigated under light and atomic force microscopy. Spoligotyping and WGS were performed to verify the identity of the strain. Results: We established a culture medium in which MTB bacilli arrest their growth, reduce their size (0.3–0.1 μm), lose their acid fastness (85–90%) and change their shape. Spoligopatterns of latent cells were identical to original H₃₇R_v, with differences observed at spacers two and 14. WGS revealed only a few genetic changes relative to the already published H₃₇R_v reference genome. Among these was a large 2064-bp insertion (RvD6), which was originally detected in both H₃₇R_a and CDC1551, but not H₃₇R_v. Conclusion: Here, we show cell-wall free cells of MTB bacilli in their latent state, and the biological adaptation of these cells was more phenotypic in nature than genomic. These cell-wall free cells represent a good model for understanding the nature of TB latency.

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Objective/Background: Paratuberculosis is an economically important, chronic, and incurable disease in ruminants, caused by Mycobacterium avium subspecies paratuberculosis (MAP). Understanding the genetic variability of MAP strains is important in diagnosis, epidemiological investigation, and the formation of strategies for prevention and control of the disease. Methods: In the present study, a total of 61 MAP isolates obtained from different parts and species of India were typed using IS1311 polymerase chain reaction-restriction endonuclease analysis (PCR-REA) to analyze the genetic difference(s), if any, between them and the host adaptation. Results: Based on PCR-REA results, bison B type was detected in 54 (87%) MAP isolates obtained from cattle, sheep, and goats. Of these, 19 were from sheep of the Rajasthan (n = 17) and Bareilly (n = 2), North India regions, 28 were from cattle of Chennai, South India (n = 3), Bareilly, North India (n = 3), and Nagpur, West India (n = 22), and seven goat isolates from Bareilly, North India region. The ‘C' type strain was detected in only seven cattle isolates obtained from the Bareilly region. Conclusion: The study revealed that in India, bison B-type MAP strains were prevalent in most of the ruminant species. These results have important epidemiological implications with regard to control and prevention of paratuberculosis in India.

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Tuberculosis is a major public health problem in developing countries. Hand and wrist is a rare localization for extra-pulmonary tuberculosis, a pseudotumoral form of soft tissue tuberculosis of the wrist is exceptional. We report the case of a 45-year-old male presenting with a painful swelling of the dorsal aspect of the right wrist evolving for six months. Clinical study was evoking a ganglion cyst of the wrist. Intraoperatively a pseudotumoral mass with rice bodies was found, suggesting tuberculous tenosynovitis. The histopathological study revealed caseating giant cell granulomas with epithelioid cells. Cultures on Löwenstein–Jensen medium detected Mycobacterium tuberculosis. Synovectomy with removal of all the rice bodies followed by anti-tuberculous chemotherapy provided uneventful recovery.

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