Tuberculosis Complex Infection Research Articles

Ruptured aortic aneurysm due to Mycobacterium bovis BCG with a delayed bacteriological diagnosis due to false negative result of the MPB 64 immunochromatographic assay

BackgroundAdjuvant therapy with bacillus Calmette–Guerin (BCG), a live attenuated strain of Mycobacterium bovis, has become the treatment of choice for low-risk superficial bladder carcinoma following transurethral resection of the bladder. Complications following vesical BCG instillations are uncommon but, in some cases, severe side-effects can occur such as sepsis or mycotic aneurysm. Besides usual laboratory techniques used for the diagnosis of Mycobacterium tuberculosis complex (MTBC) infections (smear microscopy and cultures), commercial immunochromatographic assays detecting MBP64, a 24 kDa M. tuberculosis complex-specific secretory protein, can rapidly distinguish MTBC and non-tuberculosis mycobacteria (NTM). MPB64 is found in M. tuberculosis, M. bovis and some but not all substrains of M.bovis BCG. Therefore, these immunochromatographic tests can lead to false negative results and delayed bacteriological diagnosis depending on the presence or absence of MPB64 protein in BCG substrains used for intravesical therapy.Case presentationWe report the case of a 78-year-old male patient who was admitted to the hospital because of a 1-month history of unexplained fever, thrill, weight-loss and general malaise. His past medical history was marked by a non-muscle-invasive bladder carcinoma treated by transurethral resection followed by BCG instillations (Oncotice, Merck, USA). The patient was initially treated for a urinary tract infection but as fever persists after 72 h of antibiotherapy, urinary tract ultrasound was performed and revealed a large abdominal aortic aneurysm confirmed by computed tomography. Surgery was performed after multidisciplinary discussion. Direct smear of perioperative samples revealed acid-fast bacilli and both solid and liquid cultures were massively positive. Rapid identification of the positive mycobacterial culture was performed using an immunochromatographic assay based on the detection of the Mycobacterium tuberculosis MPB 64 antigen. The result was negative for Mycobacterium tuberculosis complex. After review of the medical record, a polymerase chain reaction (PCR) was performed and gave a positive result for M. tuberculosis complex. Anti-tuberculosis therapy was started immediately and the patient evolved favorably.ConclusionsThrough this case, we showed how the utilisation of MPB64 immunochromatographic assays can provide misleading information due to the variable presence of this protein among the different BCG strains. This case further illustrates the utility of rapid TB complex-specific PCR assays which provide a more reliable identification of all MTBC species.

The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection.

The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC.

Infecção pelo complexo Mycobacterium tuberculosis em carneiro da Barbária (Ammotragus lervia) no Zoológico de Curitiba, sul do Brasil: relato de caso

A tuberculose é uma das doenças mundiais de notificação obrigatória mais importantes causada pelo complexo Mycobacterium tuberculosis que pode infectar pessoas e animais. A morte repentina de um carneiro da Barbária no Zoológico de Curitiba, que apresentou nódulos multifocais no pulmão à necropsia, levantou a suspeita de tuberculose. Foi realizada a Reação em Cadeia da Polimerase Quantitativa (qPCR) de fragmentos de órgãos e fluido. A qPCR detectou a presença do complexo M. tuberculosis nas amostras de pulmão. Este estudo relata a infecção pelo complexo M. tuberculosis no carneiro da Barbária, uma zoonose de grande relevância para a saúde pública, ressaltando-se a necessidade da implementação de medidas de prevenção. Além disso, pode prover um melhor entendimento sobre conservação de espécies, ocorrência e transmissão de doenças em cativeiro, potencial reservatório e impacto na saúde pública para visitantes e funcionários dos zoológicos.

The Incidence of Tuberculosis Transmission among Family Members and outside Households

The risk of Mycobacterium tuberculosis complex (MTBC) infection is correlated with the concentration of infectious particles and exposure time. In closed populations, healthy people staying in very frequent, close and prolonged contact with a smear-positive person, become infected and represent another link in the chain of transmission of the disease. Therefore, in the fight against tuberculosis, an important element is quick identification of the patient and potentially infected people from his environment. In epidemiological investigation of tuberculosis (TB), family members are brought under special control as they are particularly exposed to transmission of infectious diseases. The study included 150 patients with bacteriologically confirmed tuberculosis who were members of 59 families. In the years 2003-2013 this population represented all TB cases detected in Poland in a family environment.Three PCR-based genotyping methods: spoligotyping, IS6110-Mtb1-Mtb2 PCR and MIRU-VNTR typing were used. Of 150 patients, 138 could be assigned to intra-household transmission on the basis of identical DNA fingerprints upon a combined typing approach. For 12 patients in 6 households, the M. tuberculosis isolates were clearly distinct in individual analysis - IS6110-Mtb1-Mtb2 PCR, spoligotyping or MIRU-VNTR typing or in three genotyping methods, suggesting that these patients were infected by the sources in the community. The analysis confirmed the transmission of tuberculosis among members of 53 families. In the remaining 6 families the source of infection were people outside the households. In all families with young children, strains isolated from them have identical DNA patterns as strains obtained from their adult caregivers. To confirm the transmission of TB in the study population of patients, epidemiological analysis required the addition of a genotyping methods characterised by high discriminatory power.

Animal tuberculosis due to Mycobacterium bovis in Eurasian wild boar from Morocco

Eurasian wild boar (Sus scrofa) is widespread in the northern third of Morocco, Northern Africa. We aimed to investigate the presence of Mycobacterium bovis infection in wild boar and to generate information on the possible host status in this region. M. bovis was isolated in six of 43 wild boars. Culture-positive samples yielded spoligotype number SB1627. Sixty percent of lung tissue specimens or tracheobronchial lymph node samples yielded positive culture. Two thirds (64 %) of the wild boar submitted for histopathology revealed tuberculosis-compatible lesions. These lesions were particularly frequent in lymph nodes (63 %) and in lung tissue samples (43 %). Ziehl-Neelsen staining did not identify acid-fast bacilli, indicating paucibacillary infections. Our results confirm the presence of Mycobacterium tuberculosis complex (MTC) infection in Moroccan wild boar. Regarding the host status of wild boar in this region, the often generalized lesion pattern suggests a possible role of wild boar as a component of the MTC maintenance host community. However, our information was limited to 43 wild boars from one specific region. Thus, further research is needed to assess the host status of wild boar in Morocco.

Mycobacterium tuberculosis Complex and HIV Co-Infection among Extrapulmonary Tuberculosis Suspected Cases at the University of Gondar Hospital, Northwestern Ethiopia.

BackgroundExtrapulmonary Tuberculosis (EPTB) and Human Immunodeficiency Virus (HIV) infection are interrelated as a result of immune depression. The aim of this study was to determine the prevalence of Mycobacterium tuberculosis complex isolates and the burden of HIV co-infection among EPTB suspected patients.MethodAn institution based cross-sectional study was conducted among EPTB suspected patients at the University of Gondar Hospital. Socio-demographic characteristics and other clinical data were collected using a pretested questionnaire. GeneXpert MTB/RIF assay was performed to diagnosis Mycobacterium tuberculosis complex and Rifampicin resistance. All samples were also investigated by cytology and culture. The HIV statuses of all patients were screened initially by KHB, and all positive cases were further re-tested by STAT-pack. Data was analyzed using SPSS version 20 computer software and a P-value of < 0.05 was taken as statistically significant.ResultsA total of 141 extrapulmonary suspected patients were enrolled in this study. The overall prevalence of culture confirmed extrapulmonary tuberculosis infection was 29.8%, but the GeneXpert result showed a 26.2% prevalence of Mycobacterium tuberculosis complex infection. The 78.4% prevalence of extrapulmonary tuberculosis infection was found to be higher among the adult population. The prevalence of HIV infection among EPTB suspected patients was 14.1%, while it was 32.4% among GeneXpert-confirmed extrapulmonary TB cases (12/37). Tuberculosis lymphadenitis was the predominant (78.4%) type of EPTB infection followed by tuberculosis cold abscess (10.7%). Adult hood, previous history of contact with known pulmonary tuberculosis patients, and HIV co-infection showed a statistically significant association with extrapulmonary tuberculosis infection (P<0.013).ConclusionThe prevalence of culture confirmed-EPTB infection was high, and a higher EPTB-HIV co-infection was also observed.

Mycobacterial Prevalence and Antibiotic Resistance Frequency Trends in Taiwan of Mycobacterial Clinical Isolates From 2002 to 2014.

Tuberculosis, caused by Mycobacterium tuberculosis complex (MTBC) infections, is one of the most widespread infectious diseases worldwide. Nontuberculous mycobacteria (NTM) also cause chronic pulmonary infections, however, NTM infection is generally overlooked.This study analyzed the frequencies of MTBC and NTM clinical isolates from 181,132 specimens obtained from patients in Taiwan suspected of having a pulmonary mycobacterial infection from 2002 to 2014. The resistant rates to 4 first-line antibiotics (isoniazid, ethambutol, rifampicin, and streptomycin) of 9079 clinical MTBC isolates were also examined by the modified agar proportion method.Overall, the mycobacterial isolation rate was 8.65%, and this consisted of MTBC isolation rate of 5.01% and NTM isolation rate of 3.63%. The prevalence of MTBC isolates among the identified mycobacterial strains could be seen to decrease significantly from 82.5% in 2002 to 41.18% in 2014. Notably, the corresponding NTM prevalence increased 3.36 fold from 17.54% in 2002 to 58.82% in 2014. The frequencies of MTBC and NTM isolates showed a reciprocal trend with the crossing over occurring in the years 2010 and 2011. Although the resistance rates of the MTBC isolates to isoniazid and streptomycin were relatively stable over the study period, resistance rates of the MTBC isolates against rifampicin and ethambutol fluctuated across the study period. Overall, the incidence of multidrug resistance was relatively consistent at about 1.74%.The diagnosis, identification, and susceptibility tests for NTM should be standardized and integrated into appropriate clinical settings to cope with the increase in NTM infections. In addition, the documentation of the antibiotic resistance rates of MTBC clinical isolates to the antibiotic treatments most often clinically prescribed over a decade provides valuable clues and reference points for effective mycobacterial control.

Evidence of co-infection with Mycobacterium bovis and tick-borne pathogens in a naturally infected sheep flock

Ticks are responsible for the transmission of pathogens of veterinary importance, including those affecting sheep. The current study was designed to investigate co-infections with tick-borne and other pathogens in a naturally infected sheep flock with poor health condition using serology and PCR. Infection with Anaplasma ovis was detected by serology and PCR in 56% of the animals. The presence of Rickettsia spp. of the Spotted Fever Group (SFG) was detected by PCR and sequence analysis in 31% of the animals. All the animals were negative for Anaplasma phagocytophilum either by serology or PCR. Twelve sheep were randomly selected for anatomopathological studies. Five of these animals presented lesions consistent with Mycobacterium tuberculosis complex (MTBC) infection and spoligotyping confirmed infection with Mycobacterium bovis spoligotype SB0339. Co-infection with tick-borne pathogens and MTBC could contribute to the poor health condition observed in these animals but other uncontrolled factors may also be responsible. The differential expression of immune response genes supported previous findings in ruminants and suggested that infection with tick-borne pathogens and M. bovis may results in unique gene expression patterns in sheep. The results underline the need for further research into the possible role of sheep in the epidemiology of animal tuberculosis.

Prevalence and risk factors of mixed Mycobacterium tuberculosis complex infections in China

Mixed infections have been considered as a potential obstacle for tuberculosis treatment and control. To date, few studies have been done to determine the rate of mixed infections of Mycobacterium tuberculosis in China. In this study, we used the standard 24-loci MIRU-VNTR method to genotype the representative M. tuberculosis isolates from the national drug-resistant survey conducted in China. A total of 3248 M. tuberculosis complex (MTBC) strains had complete 24-loci MIRU-VNTR results and available for the analyses. Overall, MIRU-VNTR typing identified 115 (3.5%) isolates as being mixed MTBC infections in China. Statistical analysis revealed that mixed infections were significantly more likely to occur in men than women. Compared with the percentage of mixed infection from patients aged 45-56 years, the percentages of mixed infections were higher among patients aged 25-44 years [OR (95% CI): 1.844(1.129-3.014)] and old patients [older than 65 years OR (95% CI): 1.908(1.097-3.319)]. In addition, significantly higher frequencies of hemoptysis (P=0.022) and chest pain (P=0.012) were observed among mixed infections, using patients infected with a single strain as a reference. In conclusion, this study has provided the first comprehensive understanding of mixed MTBC infections in China, which will be essential to generate the effective TB control strategies.

Prevalence and risk factors of Mycobacterium tuberculosis complex infection in slaughtered cattle at Jos South Abattoir, Plateau State, Nigeria.

IntroductionBovine tuberculosis (BTB) is widespread yet poorly controlled in Nigeria hence posing a public health threat. This study determined the prevalence of Mycobacterium tuberculosis complex (MTC) and factors associated with MTC among slaughtered cattle at Jos South Abattoir in Plateau State, Nigeria.MethodsWe conducted a cross sectional study in which we collected 168 lung samples systematically from 485 slaughtered cattle from May-June, 2012, and tested for acid fact bacilli (AFB) using Ziehl-Neelsen test and a duplex polymerase chain reaction technique (PCR) for MTC detection. Data on cattle socio-demographic characteristics and risk factors for zoonotic BTB infection was obtained and analyzed using Epi info version 3.5.3 to determine frequency, proportions, and prevalence odds ratios. Multiple logistic regression was done at 95% Confidence Interval (CI).ResultsThe mean age of the cattle was 5.6 ± 1.3 years and (108) 64.3% were females. Majority were indigenous White Fulani breed of cattle (58.5%) and about half (54.8%) were slightly emaciated. Prevalence of MTB complex was 21.4% by AFB test and 16.7% by duplex PCR. Of 33 (19.6%) lungs with lesions, 27 (81.8%) were positive for AFB; while of 135 (80.4%) lungs without lesions, 9 (6.7%) were positive for AFB. Lungs with lesions were 52 times more likely to test positive to AFB test compared to tissues without lesions (AOR=52.3; 95% CI: 16.4-191.8)ConclusionThe presence of MTC in cattle signifies its potential risk to public health. Presence of lesions on lungs is a reliable indicator of MTC infection that meat inspectors should look out for.

Mixed Mycobacterium tuberculosis complex infections and false-negative results for rifampin resistance by GeneXpert MTB/RIF are associated with poor clinical outcomes.

The Xpert MTB/RIF (Xpert) assay is becoming a principal screening tool for diagnosing rifampin-resistant Mycobacterium tuberculosis complex (MTBC) infection. However, little is known about the performance of the Xpert assay in infections with both drug-sensitive and drug-resistant strains (mixed MTBC infections). We assessed the performance of the Xpert assay for detecting rifampin resistance using phenotypic drug sensitivity testing (DST) as the reference standard in 370 patients with microbiologically proven pulmonary tuberculosis. Mixed MTBC infections were identified genetically through 24-locus mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) analysis. Logistic regression was used to identify the factors associated with poor (defined as treatment failure, default, and death from any cause) or good (defined as cure or successful treatment completion) clinical outcomes. The analytic sensitivity of the Xpert assay for detecting rifampin resistance was assessed in vitro by testing cultures containing different ratios of drug-sensitive and drug-resistant organisms. Rifampin resistance was detected by the Xpert assay in 52 (14.1%) and by phenotypic DST in 55 (14.9%) patients. Mixed MTBC infections were identified in 37 (10.0%) patients. The Xpert assay was 92.7% (95% confidence interval [CI], 82.4% to 97.9%) sensitive for detecting rifampin resistance and 99.7% (95% CI, 98.3% to 99.9%) specific. When restricted to patients with mixed MTBC infections, Xpert sensitivity was 80.0% (95% CI, 56.3 to 94.3%). False-negative Xpert results (adjusted odds ratio [aOR], 6.6; 95% CI,1.2 to 48.2) and mixed MTBC infections (aOR, 6.5; 95% CI, 2.1 to 20.5) were strongly associated with poor clinical outcome. The Xpert assay failed to detect rifampin resistance in vitro when <90% of the organisms in the sample were rifampin resistant. Our study indicates that the Xpert assay has an increased false-negative rate for detecting rifampin resistance with mixed MTBC infections. In hyperendemic settings where mixed infections are common, the Xpert results might need further confirmation.

Congenital IL-12R1B receptor deficiency and thrombophilia in a girl homozygous for anIL12RB1mutation and compound heterozygous forMTFHRmutations: A case report and literature review

Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12Rβ1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She presented with disseminated Mycobacterium tuberculosis complex infection, retroperitoneal fungal abscess and also thrombosis in the superior mesenteric-portal vein junction. This is the first case report of a primary immunodeficiency associated with a genetically determined venous thrombosis.

Prevalence and risk factors of Mycobacterium tuberculosis complex infection in slaughtered cattle at Jos South Abattoir, Plateau State, Nigeria

Introduction: Bovine tuberculosis (BTB) is widespread yet poorly controlled in Nigeria hence posing a public health threat.This study determined the prevalence of Mycobacterium tuberculosis complex (MTC) and factors associated with MTC among slaughtered cattle at Jos South Abattoir in Plateau State, Nigeria.

Prevalence and risk factors of Mycobacterium tuberculosis complex infection in slaughtered cattle at Jos South Abattoir, Plateau State, Nigeria

Prevalence and risk factors of Mycobacterium tuberculosis complex infection in slaughtered cattle at Jos South Abattoir, Plateau State, Nigeria

Mycobacterium aviumSubsp.aviumInfection in Four Veal Calves: Differentiation from Intestinal Tuberculosis

Mycobacterium avium subsp. avium (Maa) is an intracellular pathogen belonging to the Mycobacterium avium-intracellulare complex (MAC). Reservoirs of MAC are the natural environment, wildlife and domestic animals. In adult bovine, MAC infections are typically caused by Mycobacterium avium subsp. paratuberculosis (Map). Maa infections in bovine are rarely reported but may cause clinical disease and pathological lesions similar to those observed in paratuberculosis or those induced by members of the Mycobacterium tuberculosis complex (MTBC). Therefore, differentiation of MAC from MTBC infection should be attempted, especially if unusual mycobacterial lesions are encountered. Four veal calves from a fattening farm dying with clinical signs of otitis media, fever, and weight loss were submitted for necropsy. Samples from affected organs were taken for histologic investigation, bacteriologic culture, and bacterial specification using PCR. Macroscopic thickening of the intestinal mucosa was induced by granulomatous enteritis and colitis. Intracytoplasmic acid-fast bacteria were detected by Ziehl-Neelsen stains and PCR revealed positive results for Mycobacterium avium subsp. avium. Clinical and pathological changes of Maa infection in veal calves had features of Mycobacterium avium subsp. paratuberculosis and the MTBC. Therefore, Mycobacterium tuberculosis complex infection should be considered in cases of granulomatous enteritis in calves.

A Multi-Antigenic Adenoviral-Vectored Vaccine Improves BCG-Induced Protection of Goats against Pulmonary Tuberculosis Infection and Prevents Disease Progression

The “One world, one health” initiative emphasizes the need for new strategies to control human and animal tuberculosis (TB) based on their shared interface. A good example would be the development of novel universal vaccines against Mycobacterium tuberculosis complex (MTBC) infection. This study uses the goat model, a natural TB host, to assess the protective effectiveness of a new vaccine candidate in combination with Bacillus Calmette-Guerin (BCG) vaccine.Thirty-three goat kids were divided in three groups: Group 1) vaccinated with BCG (week 0), Group 2) vaccinated with BCG and boosted 8 weeks later with a recombinant adenovirus expressing the MTBC antigens Ag85A, TB10.4, TB9.8 and Acr2 (AdTBF), and Group 3) unvaccinated controls. Later on, an endobronchial challenge with a low dose of M. caprae was performed (week 15). After necropsy (week 28), the pulmonary gross pathology was quantified using high resolution Computed Tomography. Small granulomatous pulmonary lesions (< 0.5 cm diameter) were also evaluated through a comprehensive qualitative histopathological analysis. M. caprae CFU were counted from pulmonary lymph nodes.The AdTBF improved the effects of BCG reducing gross lesion volume and bacterial load, as well as increasing weight gain. The number of Ag85A-specific gamma interferon-producing memory T-cells was identified as a predictor of vaccine efficacy. Specific cellular and humoral responses were measured throughout the 13-week post-challenge period, and correlated with the severity of lesions.Unvaccinated goats exhibited the typical pathological features of active TB in humans and domestic ruminants, while vaccinated goats showed only very small lesions. The data presented in this study indicate that multi-antigenic adenoviral vectored vaccines boosts protection conferred by vaccination with BCG.

Pustular Skin Lesions in a Patient With Advanced HIV Infection and Pneumonia

Diagnosis: Tuberculosis cutis miliaris acuta generalisata in the context of advanced human immunodeficiency virus (HIV) infection. Histopathological findings on the skin biopsy (Figure 1) revealed superficial dermal granulomatous inflammation (Figure 2) and acid-fast bacilli (Figure 3). Empirical treatment for tuberculosis and Mycobacterium avium complex (MAC) infection was commenced with rifampicin, isoniazid, pyrazinamide, ethambutol, and clarithromycin. Mycobacterium tuberculosis complex (MTB) polymerase chain reaction (PCR) performed on the skin biopsy specimen was positive and clarithromycin was discontinued. The fever defervesced within 48 hours. Over the subsequent weeks, fully sensitive MTB was cultured from blood cultures, sputum, bronchoalveolar lavage fluid, and urine from the acute admission. Cutaneous tuberculosis has long been recognized as a clinical syndrome having been first described by Laennec in 1826. It continues to be an important but rare clinical manifestation of tuberculosis in a resource-rich setting [1] with highly variable skin findings. Direct inoculation from an exogenous source, Figure 1. Multiple pustular skin lesions on upper limb (arrows). Figure 2. Hematoxylin-eosin stain of skin biopsy (×100 magnification) showing superficial dermal granulomatous inflammation (arrow).

Specific and Rapid Detection ofMycobacterium tuberculosisComplex in Clinical Samples by Polymerase Chain Reaction

Background. Tuberculosis, a global health problem and highly prevalent in India, has always been a serious problem with respect to definitive diagnosis. Polymerase chain reaction (PCR) techniques are now widely used for early detection and species differentiation of mycobacteria, but mostly with their own limitations. We aim to detect and differentiate Mycobacterium tuberculosis (Mtb) infections by choosing appropriate target sequences, ideally present in all mycobacterial species (MTB complex) and absent in others. Methods. Amplification of three target sequences from unrelated genes, namely, hsp 65 (165 bp), dnaJ (365 bp), and insertion element IS 6110 (541 bp) by PCR was carried out in clinical samples from suspected cases of tuberculosis/ mycobacterioses and healthy controls. Results. The sensitivity of this method ranged from 73.33% to 84.61%, and the specificity was 80%. The PCR method was significantly better (P = 0.03 and P = 0.009) than both smear and culture methods. Conclusion. Our trimarker-based PCR method could specifically detect M. tuberculosis and MTB complex infection from that of major pathogenic NTM and nonpathogenic mycobacteria. This method, by well distinguishing between MTB complex and NTM, presented a fast and accurate method to detect and diagnose mycobacterial infections more efficiently and could thereby help in better patient management particularly considering the increase in mycobacterial infections due to emergence of NTM over the past decades.

Characteristics of suppressor macrophages induced by mycobacterial and protozoal infections in relation to alternatively activated M2 macrophages.

In the advanced stages of mycobacterial infections, host immune systems tend to change from a Th1-type to Th2-type immune response, resulting in the abrogation of Th1 cell- and macrophage-mediated antimicrobial host protective immunity. Notably, this type of immune conversion is occasionally associated with the generation of certain types of suppressor macrophage populations. During the course of Mycobacterium tuberculosis (MTB) and Mycobacterium avium-intracellulare complex (MAC) infections, the generation of macrophages which possess strong suppressor activity against host T- and B-cell functions is frequently encountered. This paper describes the immunological properties of M1- and M2-type macrophages generated in tumor-bearing animals and those generated in hosts with certain microbial infections. In addition, this paper highlights the immunological and molecular biological characteristics of suppressor macrophages generated in hosts with mycobacterial infections, especially MAC infection.

Clinical immunology Disseminated Mycobacterium tuberculosis complex infection in a girl with partial dominant IFN-γ receptor 1 deficiency

Clinical immunology Disseminated Mycobacterium tuberculosis complex infection in a girl with partial dominant IFN-γ receptor 1 deficiency