Objective/Background: Extrapulmonary tuberculosis (EPTB), which accounts for 10%–40% of the global burden of TB, with the highest incidence in Sub-Saharan Africa, is strongly associated with human immunodeficiency virus infection. Diagnosing EPTB is challenging, and recently, there has been a concerted effort to evaluate the latest molecular diagnostics for diagnosing TB in a range of specimen types. The Xpert MTB/RIF assay (Cepheid, Sunnyvale, CA, USA) is one such technology, which simultaneously detects Mycobacterium tuberculosis and rifampicin resistance. Our objective was to evaluate the accuracy of the Xpert MTB/RIF assay for the diagnosis of EPTB and detection of rifampicin resistance in routinely processed formalin-fixed, paraffin-embedded (FFPE) tissues, compared with histological detection of TB as the gold standard. Methods: A convenience set of 100 biobanked FFPE tissues, including lymph nodes (n = 64), male genital tract tissue (n = 10), abdominal tissue (n = 8), female genital tissue (n = 5), breast tissue (n = 5), synovial tissue (n = 4), skin (n = 2), tongue tissue (n = 1), and thyroid (n = 1), from routine cases of clinically suspected EPTB admitted to the University Teaching Hospital, Lusaka, Zambia, were analyzed using the Xpert MTB/RIF assay and in-house polymerase chain reaction (PCR) assay targeting IS6110, in parallel with Ziehl–Neelsen (ZN) staining, against histology as the gold standard. Results: Some 66% of specimens had histological evidence of TB infection. ZN staining was positive for TB in 8% of cases, and Xpert MTB/RIF was positive for TB in 25% of cases. Taking histology as the gold standard, the sensitivity and specificity were as follows: In lymph tissue the accuracy of the Xpert MTB/RIF assay was 41% (95%CI 27-57), not significantly better than ZN or the in-house PCR assay. In non-lymph tissue the sensitivity of the in-house PCR assay was 82% (95%CI: 56%-95%), significantly higher than the Xpert MTB/RIF assay (P = 0.004). The Xpert MTB/RIF assay indicated rifampicin resistance in just three cases. Conclusion: The Xpert MTB/RIF assay is potentially a useful tool for the diagnosis of TB in routine FFPE tissues.

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Objective/Background: Nontuberculous mycobacterial (NTM) species are assuming public health importance in pulmonary diseases; they are increasingly being isolated, and importantly, most NTMs do not respond to routine tuberculosis (TB) drugs. This study aimed to identify NTMs isolated from pulmonary TB cases and also determine their susceptibility to streptomycin (STR), isoniazid (INH), and rifampicin (RIF). Methods: A total of 1755 mycobacterial isolates, obtained between August 2012 and July 2014, from 2036 smear-positive pulmonary cases were identified using polymerase chain reaction amplification of IS6110, and hsp65 gene sequencing analysis. Drug susceptibility testing (DST) was then performed for the identified NTMs against STR, INH, and RIF using microplate Alamar blue assay. The results were analyzed against patients' biodata for statistical associations. Results: Of the 1755 analyzed isolates, we identified 43 (2.5%) NTMs, which included 18 (41.9%) Mycobacterium intracellulare, 13 (30.2%) Mycobacterium avium subs. paratuberculosis, 5 (11.3%) Mycobacterium abscessus, 3 (7.0%) each of Mycobacterium mucogenicum and Mycobacterium colombiense, and 1 (2.3%) Mycobacterium simiae. Patients infected with NTMs (52.0%) were more likely to be human immunodeficiency virus-positive (P = 0.001, odds ratio = 6.6, 95% confidence interval = 2.7–16.2) than those infected with M. tuberculosis complex (5.8%). All the 43 (100%) NTMs were resistant to INH, whereas 32 (74%) and 19 (44%) were resistant to RIF and STR, respectively. Furthermore, 16 (37.2%) NTMs were resistant to all three drugs, 20 were resistant to INH and RIF, and 3 were resistant to STR and INH. All the M. abscessus isolates were resistant to all the three drugs, whereas all the M. avium isolates were resistant to INH and RIF, but only three were resistant to STR. Among the M. intracellulare isolates, 8, 18, and 15 isolates were resistant to STR, INH, and RIF, respectively. Conclusion: The observed high-resistance level to INH and RIF supports the need for rapid species identification and DST of nonresponding TB cases before retreatment.

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Objective/Background: The aim of this study was to analyze the detection of nontuberculous mycobacterial (NTM) species derived from sputum specimens of pulmonary tuberculosis (TB) suspects. Increasing prevalence and incidence of pulmonary infection by NTM species have widely been reported in several countries with geographical variation. Materials and Methods: Between January 2014 and September 2015, sputum specimens from chronic pulmonary TB suspect patients were analyzed. Laboratory examination of mycobacteria was conducted in the TB laboratory, Department of Clinical Microbiology, Dr. Soetomo Hospital, Surabaya. Detection and identification of mycobacteria were performed by the standard culture method using the BACTEC MGIT 960 system (BD) and Lowenstein–Jensen medium. Identification of positive Mycobacterium tuberculosis complex (MTBC) was based on positive acid-fast bacilli microscopic smear, positive niacin accumulation, and positive TB Ag MPT 64 test results (SD Bioline). If the growth of positive cultures and acid-fast bacilli microscopic smear was positive, but niacin accumulation and TB Ag MPT 64 (SD Bioline) results were negative, then the isolates were categorized as NTM species. MTBC isolates were also tested for their sensitivity toward first-line anti-TB drugs, using isoniazid, rifampin, ethambutol, and streptomycin. Results: From 2440 sputum specimens of pulmonary TB suspect patients, 459 isolates (18.81%) were detected as MTBC and 141 (5.78%) as NTM species. Conclusion: From the analyzed sputum specimens, 18.81% were detected as MTBC and 5.78% as NTM species. Each pulmonary TB suspect patient needed clinical settings to suspect causative agents of MTBC and/or NTM species; clinicians have to understand the local epidemiological data for the evaluation of causes of lung infection to determine appropriate therapy.

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Objective/Background: Clinical diagnosis of indeterminate and tuberculoid leprosy is often difficult due to limited and confounding signs and symptoms. In the current study, we evaluated the utility of new multiplex polymerase chain reaction (PCR) using Mycobacterium leprae-specific DNA sequences in the pseudogene regions of ML1545, ML2180, and ML2179 for PCR-based diagnosis of indeterminate leprosy (IND) and leprosy cases across the immunological spectrum. The sensitivity was compared with that of RLEP PCR. Methods: DNA was extracted from paraffin-embedded skin biopsy specimens of 220 leprosy cases, which were divided into IND (41), tuberculoid form (3), borderline tuberculoid (42), midborderline (3), borderline lepromatous (n=59), and lepromatous leprosy (72) cases. PCR positivity of both multiplex and RLEP PCR were compared in all the samples. A decision tree was constructed using the classification and regression trees algorithm to predict the probability of PCR positivity with the new multiplex PCR scheme in various clinical groups of leprosy. Sensitivity of each pseudogene target was determined using real-time PCR assays, and specificity was confirmed by PCR amplification of DNA extracted from three other mycobacterial species and skin biopsies of 44 non-leprosy cases. Results: A multiplex PCR positivity of 75.61% was noted in IND cases when compared to that of 58.54% using RLEP PCR (P < 0.05). Enhanced multiplex PCR positivity was noted across various clinical groups in comparison to RLEP PCR. The decision tree classifier has predicted statistically significant probability for multiplex PCR positivity among RLEP-PCR negative group and clinical groups with a low bacillary load. Conclusion: This new multiplex PCR scheme can support the diagnosis of indeterminate and tuberculoid forms of leprosy with limited clinical manifestations and can be implemented in basic clinical/diagnostic setting that possess conventional PCR facilities.

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Background: Port-site infection (PSI) is a prevailing, chronic, nagging, treatment refractory complication of laparoscopic surgery (LS). It neutralizes the advantages of minimally invasive surgery and increases morbidity, treatment cost of patient, leading to loss of confidence on operating surgeon. PSIs are preventable with appropriate preoperative, intraoperative, and postoperative measures. Atypical mycobacterium is most commonly associated with nonhealing postlaparoscopic wound infections, causing outbreaks or sporadic cases worldwide. Purpose: We retrospectively studied the occurrence of nontuberculous mycobacterium (NTM) from PSIs following LS that did not respond to antibiotics used for pyogenic infections and having sterile routine aerobic cultures and their antimicrobial susceptibility pattern to guide proper management. Methods: The study was done in a tertiary care hospital of Eastern India over a 1-year period which included PSI cases with delayed onset not responding to antibiotics, following different types of LS. Pus/discharge from 32 patients was collected and examined for isolation and identification of the causative agents. Gram stain and Ziehl–Neelsen staining methods were used for direct examination. Culture media included blood agar, Robertson's cooked meat broth, MacConkey agar, and Lowenstein–Jensen medium. Isolates from the cases were identified using biochemical tests or molecular methods and studied the antimicrobial susceptibility pattern by the standard microbiologic procedures. Results: Mycobacterium abscessus (13) and Mycobacterium fortuitum (2) were isolated from 15 serosanguinous drainage obtained from 32 cases by routine microbiological techniques. All isolates analyzed for antimicrobial susceptibility pattern were highly sensitive to clarithromycin (93.3%), amikacin (93.3%), and imipenem (80%) but were variable to ciprofloxacin, ofloxacin, and linezolid. Conclusions: Our present study shows frequent association of NTM with laparoscopic port-site nonhealing chronic infection or wound dehiscence. Although direct microscopy can give us a clue to diagnosis, culture isolation is required for speciation and antimicrobial susceptibility testing, which helps formulate therapeutic regimen.

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Objective/Background: Tuberculosis (TB) remains one of the most important infectious diseases. Although Mexico is one of the Latin American countries with the largest contribution to these statistics, there are few reports that describe the genotypic characteristics of TB. The aim of this study was to use the MIRU-VNTR-24 loci to analyze the genetic diversity of M. tuberculosis circulating in the state of Veracruz, Mexico. Methods: Here, we analyze by MIRU-VNTR-24 loci 80 clinical isolates from individuals with confirmed TB from Veracruz México, also clinical and epidemiological variables were recovered and analyzed. Results: Of the individuals included in the analyses 65% were from men with an average age of 42 (± 17) years, 17% and 6% were drug and multi-drug resistant. 88% of the isolates were included in 20 clusters, of which 52% were classified into twelve orphan clusters and the remaining 37% were distributed among eight lineages: LAM (10%), EAI (9%), Haarlem (8%), H37Rv (4%), S (4%) and TUR (2%). Conclusion: An important diversity of lineages and unknown genotypes was identified; however, more studies are necessary in order to understand the characteristics of the genotypes displayed in the region. There is no doubt regarding the need for a molecular epidemiological surveillance system that can help to evaluate the dynamics of genotypes circulating in the country and support strategies for the prevention and management of populations affected by TB.

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Objective/Background: Introduction of the interferon gamma (IFN-γ) release assays with their higher sensitivity and specificity over the traditional tuberculin skin test has improved testing for latent tuberculosis infection (LTBI). None of the IFN-γ release assays has ever been used to screen for LTBI in Ghana. This study set out to determine the utility of the QuantiFERON TB Gold-in-Tube (QFT-GIT) test for the diagnosis of LTBI among close household contacts of newly diagnosed sputum smear-positive tuberculosis (TB) patents in Accra, Ghana, and the associated risk factors for a positive QFT-GIT test. Materials and Methods: Close household contacts of newly diagnosed sputum smear-positive patients receiving anti-TB therapy from three hospitals in Accra were recruited, after providing written informed consent, between April 2012 and December 2014. In addition to demographic details, 2 mL of blood was collected from all participants for the QFT-GIT test for LTBI diagnosis. Results: Out of 112 eligible consenting participants, the QFT-GIT test was performed for 100 participants. The prevalence of LTBI (QFT-GIT positive) was 65%, with 32% being QFT-GIT negative and 3% indeterminate results. Contacts aged >15 years were more likely to be QFT-GIT positive than those aged >15 years, regardless of their Bacillus Calmette–Guerin status. There was significantly higher QFT-GIT test positivity in adult contacts who were parents, siblings, or spouses to index cases than in child contacts (P = 0.0016, P = 0.04, and P = 0.0003, respectively). Conclusion: The QFT-GIT test will be a useful tool for screening of TB contacts for LTBI in Ghana.

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Objective/Background: To determine the prevalence of undiagnosed active pulmonary tuberculosis (PTB) cases and sensitivity, specificity, and positive and negative predictive values of symptom combinations for undiagnosed TB infection in human immunodeficiency virus (HIV)-positive and HIV-negative pregnant mothers attending antenatal care (ANC) clinics. Mycobacterium TB and HIV are the leading causes of death among women of reproductive age worldwide. Symptom screening is the first step in the World Health Organization (WHO)-recommended TB intensified case finding algorithm for people living with HIV. However, the symptom-based PTB screening method for pregnant mothers is suboptimal and needs further optimization as some of the symptoms are obscured by the physiological changes during pregnancy. Materials and Methods: This was a cross-sectional study, which was conducted from June 2014 to May 2015 at 16 public health institutions in Mekelle and its surrounding areas. All pregnant mothers who visited the maternity clinics for routine ANC follow-up examinations were screened for PTB symptoms. Those who had at least 2 weeks of cough, in addition to other symptoms, were enrolled in the study. Sociodemographic and clinical data and sputum samples were collected by midwives and nurses. The sputum samples were shipped to the Tigray Regional Laboratory and stored at −80°C until TB culture was performed. Results: Between June 2014 and May 2015, 9600 pregnant mothers were screened for PTB symptoms. We collected 174 sputum samples from pregnant mothers who had ≥2 weeks of productive cough. The participant's median age was 27.5 years (interquartile range, 24–31 years). During enrollment, 604 (6.28%) participants were HIV seropositive. Among the HIV-positive mothers, 17 (38.1%) were informed about their HIV status when they visited the health institutions for ANC follow-up, whereas the remaining 27 (61.9%) were already on antiretroviral therapy. All sputum samples (n = 174) were cultured using Löwenstein–Jensen medium at the Tigray Regional Laboratory. One of the 174 sputum samples was positive (+1) in Ziehl–Neelsen staining technique, and none of them was TB culture positive. During the study, at all study sites, no pregnant mother was even presumptively diagnosed and treated for TB during the routine ANC services. Conclusion: Although the survey did not find any active PTB case among pregnant mothers, we identified 174 PTB-susceptive cases during the routine ANC services. Therefore, it was concluded that the integration of the WHO-recommended four-part symptom-based intensified case finding as one of the core components of ANC services can enhance the early detection of PTB, especially in high TB-burden countries.

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Hemophagocytic syndrome is a life-threatening disease characterized by the uncontrolled activation of macrophages, resulting in hemophagocytosis of blood cells in the bone marrow. A 20-year-old gravida at 23-week and 5-day gestation was admitted to hospital to evaluate fever up to 104°F of unknown origin, moderate cytopenia, and elevated levels of liver enzymes. Bone marrow biopsy confirmed hemophagocytic syndrome, and polymerase chain reaction came back positive for Mycobacterium tuberculosis. Supportive care and tuberculosis treatment resulted in clinical improvement. At 27 weeks and 5 days, premature rupture of the membranes occurred, and because of the high probability of reactivating the hemophagocytic syndrome, a cesarean section was performed at 29-week and 2-day gestation. Hemophagocytic syndrome is an uncommon disease which rarely appears during pregnancy. Early diagnosis and treatment can save both maternal and fetal lives.

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Tuberculosis (TB) is a leading cause of death worldwide. It can affect any organ. However, cardiac involvement is extremely rare. Anti-TB therapy has been proved to be effective and curative in majority of TB cases except TB myocarditis, where it is found to be fatal. We describe three cases with confirmed TB with impaired left ventricular systolic function and low ejection fraction. All three cases improved clinically and left ventricular function returned to normal within a few weeks after the commencement of TB therapy.

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Introduction: Information on the long-term treatment outcome following nontuberculous mycobacterial (NTM) lymphadenitis is very limited. We performed a study to (a) compare cure rates following different initial treatment courses, (b) describe subsequent treatment courses and their outcomes, and (c) determine the occurrence of late sequelae in immunocompetent children with NTM lymphadenitis. Materials and Methods: In 2011, we conducted a retrospective follow-up study in 71 parents whose children had been hospitalized with NTM disease 2002–2005. A telephone survey was performed using a standardized questionnaire to collect information on the therapeutic management and treatment outcome. Results: Of 61 children with NTM lymphadenitis, 33 (54%) children were cured after the initial treatment. We found no significant difference in cure rates following surgical intervention only (45%, 13/29 children) and a combination of surgical intervention and chemotherapy (61%, 19/31 children). In 7 out of 11 children, the cure rate following complete lymph node excision was 64%. Subsequent courses of treatment including repeated surgical intervention, combination therapy, chemotherapy only, and wait-and-see strategy in children where initial therapy failed resulted in the cure of all 61 children. In four children (7%), recurrences were observed up to 5 years later. Conclusions: Our study showed that recurrent NTM lymphadenitis might be observed several years after initial resolution of disease. The cure rate following complete lymph node excision was lower than reported in other studies. Subsequent treatment courses were necessary in half of the children. Physicians and parents need to be aware that NTM lymphadenitis in children requires careful choice of intervention and active follow-up.

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Objective/Background: There are several methods used to screen for latent tuberculosis (TB) infection (LTBI) including the QuantiFERON-TB Gold-in-Tube (QFT-GIT) and T-SPOT-TB (T-SPOT) tests. Many studies have reported the equivalence of these two methods, but it is unclear which of them is more cost effective. We investigated the age and cost issues of these tests in screening for LTBI among health-care workers. Materials and Methods: One hundred and forty new employees during 2008–2011 in our hospital were screened using the QFT-GIT test, and 140 new employees during 2011–2014 were screened with the T-SPOT test for LTBI. The results of both tests were classified as positive, undetermined (retesting required), or negative. Results: There were six positive results (4.29%), eight undetermined results (5.71%), and 126 negative results (90.0%) with the QFT-GIT test. As for the T-SPOT test, there were eight positive results (5.71%), three undetermined results (2.14%), and 129 negative results (92.1%). Fourteen LTBI employees (6 in QFT-GIT and 8 in T-SPOT) were detected statistically equally using the two methods (P = 0.79). The total costs, including those incurred for retesting, were $7,711.86 (US dollar) and $6,525.42 for the QFT-GIT and T-SPOT tests (cost of one test is $55.08 for QFT-GIT and $46.61 for T-SPOT), respectively. Conclusion: T-SPOT is one of the options for screening for LTBI partly owing to the viewpoint of cost-effectiveness. Further prospective studies need to be considered for a definitive conclusion.

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Introduction: Tuberculosis (TB) and diabetes mellitus (DM) are both important health issues, and the association between DM and TB may be the next challenge for global TB control worldwide, type 2 DM (T2DM) responsible for 90% of DM cases. Persons with diabetes have a significantly increased risk of active TB, which is two to three times higher than in persons without diabetes. The aim of this study was to determine the association between pulmonary tuberculosis (PTB) and T2DM among Sudanese patients and also to determine the association between hemoglobin A1c (HbA1c) percentage in diabetic patients and development of PTB and effect of duration of T2DM in developing PTB. Materials and Methods: A total of 120 sputum samples were collected from patients during 6 months in Ribat University Hospital, Khartoum, Sudan. Sixty of them were known type 2 diabetic patients categorized as study group and sixty were nondiabetic patients categorized as control group. Ziehl–Neelsen smear preparation and DNA were extracted from sputum for detection of Mycobacterium tuberculosis by polymerase chain reaction (PCR). Results: Among the 120 sputum specimens, 72 (60%) were males and 48 (40%) were females. Fourteen (19.4%) males and 6 (12.5%) females had PTB, the difference was not statistically significant according to gender P = 0.229. According to treatment modalities, diabetic patients were treated with injectable insulin (36.7%), PCR positive was 4(33.3%) P value (0.853), oral hypoglycemic drugs (51.7%) PCR positive 7 (58.3%) P value (0.849) and dietary control (11.7%) PCR positive (1 (8.3%) P value (1.000) Were insignificant differences. The frequency of HbA1c of 58 patients with diabetes was 24 (41.4%) who had controlled DM (HbA1c level ≤ 6.5%) and 34 (58.6%) had uncontrolled DM. Of the 60 patients with diabetes, 12 had PTB with uncontrolled DM, with significant difference (P=0.000). The mean duration of diabetes mellitus was (6.92 years ± Std 6.801) and the frequency of diabetes mellitus in first 10 years was 47 (78.3%), in (11-20) years was 10 (16.7%) and in (21-30) years was 3 (5%), the PCR positive PTB showed 10(21.3%) for the first 10 years, (11-20) years was 2 (20%) and zero (0.0%) for (21-30) years, P-value (0.480) insignificant different. Conclusions: In summary, we found consistent evidence for an increased risk of TB among patients with uncontrolled DM (high-level HbA1c).

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Objective/Background: Mycobacterium cosmeticum, first described in 2004, was recovered from a patient undergoing a cosmetic procedure. Subsequently, this species was associated with an outbreak in a nail salon. In all cases, the isolates were susceptible to all antibiotics tested. Recently, however, we recovered a strain of M. cosmeticum from the Chesapeake Bay, resistant to 11 of 14 antimicrobials. The objective of this work was to present our findings on the resistance and susceptibility of this isolate to various antibiotics. Materials and Methods: Surface water samples were collected from 10 sites in the Chesapeake Bay and upper tributaries to assess microbial diversity and antibiotic resistance. Site selection was based on proximity to agricultural runoff, industrial contaminants, and sewage effluents. Samples were processed and recovered organisms were identified and subjected to antimicrobial-susceptibility testing. Results: One nontuberculous species, identified as M. cosmeticum, was recovered from Sandy Point State Park. Resistance was detected to several antibiotics: doxycycline (16 μg/mL), tigecycline (≥4 μg/mL), clarithromycin (8 μg/mL), trimethoprim/sulfamethoxazole (≥8/152 μg/mL), imipenem (32 μg/mL), cefoxitin (32 μg/mL), ethionamide (≥20 μg/mL), and streptomycin (16 μg/mL). Of the 14 antibiotics tested, only the fluoroquinolones, linezolid, and amikacin demonstrated potent activity with susceptible minimum inhibitory concentrations. Conclusion: The antimicrobial resistance identified in this M. cosmeticum isolates from the Chesapeake Bay raises some important concerns: (a) why is the susceptibility pattern in this isolate so different from the previously published reports, (b) how did resistance emerge in this isolate, (c) is there a source of environmental exposure to antibiotics, (d) is it a human isolate transferred to the watershed, or (e) is it the result of lateral gene transfer with other resistant organisms in the Bay?

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Introduction: The nucleic acid amplification tests (NAATs): Line probe assay and GeneXpert (Xpert) have evolved as the primary tool for identification of rifampicin (RIF)-resistant (RR) tuberculosis (TB) worldwide, primarily because of the ease and speed. We rechecked RR isolates identified by NAATs from presumptive RR TB cases belonging to South India by the Revised National TB Control Program, India using multiple RIF concentrations on Bactec MGIT system and compared the mutation patterns with the resistance levels. Methodology: Standard protocol for Bactec MGIT system as given by the manufacturer modified for the multiple RIF concentrations was used. All the retests were done in a certified BSL3 laboratory. Results: We found that there is a mismatch of up to 20% (RIF breakpoint 0.5 mg/L); the NAATs probably overidentifying RR TB. Half of the cases with mismatch showed a sub-breakpoint rise in resistance level (0.125 mg/L to 0.5 mg/L RIF). Discussion and Conclusion: The probable reasons for the mismatch are “sub-breakpoint low-level resistance mutants,” hetero-resistant bacterial populations, and other inherent test limitations along with the low RR TB prevalence in South India (<5%) among “presumptive multidrug-resistants.” This could be due to the incomplete selection pressure by an inadequate RIF exposure caused by various factors including a low-RIF dosage being used widely and poor Directly observed treatment. To prevent the false diagnosis of RR TB in a massive scale when using NAATs, we may need to enforce a carefully targeted testing approach and a phenotypic susceptibility testing with multiple RIF concentrations for confirmatory purposes.

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Tuberculosis (TB) is still endemic in many developing countries. Involvement of wrist joint is very rare, and the diagnosis is often missed. We present a case of isolated TB of the wrist, which was confirmed with intraosseous tissue histopathological examination in a 10-year-old boy. Antibacterial chemotherapy during 12 months promoted healing and good outcome.

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Background: Tuberculosis (TB) ranks as the second leading cause of deaths due to infectious diseases. Although global efforts have been made to control TB, still, this is a serious threat as Mycobacterium tuberculosis (MTB) produced resistance against both the first- and second-line drugs. The increasing incidence of multidrug-resistant, extremely drug resistant, and totally drug-resistant TB worldwide requires extra efforts to search for new anti-TB drugs. Materials and Methods: The present study evaluated the antimycobacterial activities of Citrullus colocynthis, Calotropis procera, Ricinus communis, Capparis decidua, and Fagonia cretica plants' extracts against rifampicin-sensitive (H37Rv) and rifampicin-resistant (TMC331) strains of MTB. Results: Out of 44 extracts, 19 extracts were found active against H37Rv sensitive strain. Highest activities were observed in chloroform extract of C. colocynthis (leaves) and n-hexane extract of R. communis (seeds) with minimum inhibitory concentration values of 2.5 mg/ml each. Conclusions: Results show antimycobacterial potential in some of the fractions of studied plants that may be utilized further for isolation of active compounds and as a possible cure against TB.

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Background: Drug-resistant tuberculosis (DR-TB) continues to be a challenge in developing countries with poor resources. Despite the high prevalence of primary DR-TB, its routine screening prior to the treatment is not performed in public hospitals in Nigeria. Data regarding drug resistance and its genetic determinant among follow-up patients with TB are lacking in Nigeria. Hence, the aim of this study was to determine the prevalence and genetic determinant of drug resistance among the follow-up patients with TB in a tertiary hospital in Nigeria. Materials and Methods: This was a cross-sectional, laboratory-based study conducted on 384 sputum samples collected from consented follow-up patients with TB. Standard microbiology methods (Ziehl–Neelsen staining and microscopy) and polymerase chain reaction (PCR; line probe assay [LIPA]) were used to analyze the collected samples. Pearson's Chi-square test was used to analyze the generated data. Results: Out of 384 sputum samples analyzed for Mycobacterium tuberculosis and DR-TB, 25 (6.5%) tested positive for acid-fast bacilli. These samples were subjected to PCR (LIPA), of which 18 (72%) tested positive for DR-TB. Of these 18 samples, mutations conferring resistance to rifampicin (rpoB) and isoniazid (katG and/or inhA) were detected in 12 (66.7%) and 6 (33.3%) samples, respectively. Transmission dynamics of DR-TB was not significantly (P > 0.05) dependent on demographic characteristics. Conclusion: There is a need to strengthen the laboratory capacity for the diagnosis of TB and drug resistance testing and make these services available, affordable, and accessible to the patients who need them.

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Objective/Background: Mycobacterium lepraemurium (MLM), the etiologic agent of murine leprosy, is an intracellular parasite of macrophages; the mechanism used by this bacterium to enter macrophages is not known. The fate of the MLM phagosome inside macrophages is also unknown. This study was conducted to investigate how MLM enters macrophages and to define the maturation process of MLM phagosome inside macrophages. Materials and Methods: Peritoneal macrophages were incubated in the presence of mannan–bovine serum albumin (BSA), and antibodies to known macrophage receptors, including, anti-FcγRIII/RII (anti-CD16/32), anti-CD35 (anti-CR1), anti-TLR2, anti-TLR4, anti-TLR6, anti-CD14, and anti-dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN). Then, macrophages were challenged with Iris Fuchsia-stained MLM, at a multiplicity of infection of 50:1. The blocking effect of the antibodies (and mannan–BSA) used was analyzed using direct microscopy and flow cytometry. The maturation process of MLM phagosomes was visualized by their interaction with antibodies to Rab5, Rab7, proton ATPase, and cathepsin D, by confocal microscopy. Results: Only mannan–BSA and anti-TLR6 antibody significantly blocked the entry of MLM into macrophages. None of the other antibodies, including that for DC-SIGN, meaningfully inhibited the endocytic process. We also found that MLM is a fusiogenic mycobacterium. This was deduced from the orderly association of MLM phagosomes with Rab5, Rab7, Proton ATPase, and lysosomes (cathepsin D). Conclusion: Fusion of MLM phagosomes with lysosomes seems to be a necessary event for the intracellular multiplication of MLM; similar to Mycobacterium leprae, this microorganism hardly grows on artificial, synthetic, bacteriologic media.

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Objective/Background: Mycobacterium tuberculosis thymidine monophosphate kinase (mtTMPK) is a potential enzymatic target for the treatment of tuberculosis (TB). Materials and Methods: In this study, we performed pharmacophore-based in silico screening, targeting mtTMPK with a compound library of 461,383 chemicals. We evaluated the candidate compounds for inhibitory effects on the growth of the model mycobacteria, Mycobacterium smegmatis. Results: The compound KTP3 completely inhibited the growth of M. smegmatis at 100 μM. A similarity search and rescreening with the structure of compound KTP3 using a web-based database identified two similar compounds (KTPS1 and KTPS2) with improved potency. The KTP3 analogs, KTPS1 and KTPS2, exhibited strong growth inhibitory effects with half-maximal inhibitory concentration values of 8.04 μM and 17.1 μM, respectively, against M. smegmatis. Moreover, the most potent chemical compound, KTPS1, did not exhibit toxic effects on the model enterobacteria and several mammalian cells. Two active chemicals, KTPS1 and KTPS2, inhibited mtTMPK activity by 18% and 36%, respectively, suggesting that these compounds have off-target activities against Mycobacterium. Conclusion: Structural and biological information on these chemicals is likely to be useful for the development of novel antibiotics for the treatment of TB.

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Objective/Background: Global indices show that Nigeria has the highest tuberculosis (TB)-related mortality rate. Overdependence on Ziehl–Neelsen (ZN) smear microscopy for diagnosis and human immunodeficiency virus (HIV)/AIDS has limited control efforts. The new polymerase chain reaction-based XpertMTB/Rif (Cepheid Inc., CA, USA), which detects Mycobacterium tuberculosis and rifampicin resistance, was introduced in Cross River State in 2014. We evaluated the increment in pulmonary TB case detection following introduction of XpertMTB/Rif into the Cross River State TB control program. Materials and Methods: Data from three XpertMTB/Rif centers in Cross River were prospectively collected from June 2014 to December 2015. One spot specimen and one early morning sputum specimen were collected from each patient and tested using microscopy while one specimen was used for XpertMTB/Rif. Results: A total of 2326 patients comprising 47.4.0% (1103) males and 52.6% (1223) females were evaluated. Their mean age was 38.8 years (range 4–89 years); 42.6% (991) were HIV positive and 50.9% (1183) HIV negative, and for 6.5% (158) HIV status was unknown. XpertMTB/Rif detected M. tuberculosis in 22.9% (534) of patients, while 16.8% (391) were ZN smear positive. Smear microscopy missed 24.5% (131/534) of cases (P < 0.0001). When patients where categorized according to HIV status, XpertMTB/Rif detected 23.7% (280/1183) and ZN smear microscopy detected 18.5% (219/1183) of HIV-negative patients. XpertMTB/Rif detected 21.5% (213/991) and ZN smear 14.1% (140/991) of HIV-positive patients. TB case detection was significantly higher in HIV-negative patients than in HIV-positive patients when either XpertMTB/Rif and/or ZN was used (P = 0.018 and 0.012, respectively). Conclusion: The use of XpertMTB/Rif has significantly increased TB case detection and data in Cross River State. Scale-up of additional strategies such as culture is still required to improve TB detection in HIV patients.

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