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Tuberculosis in Birds: Insights into the Mycobacterium avium Infections  [PDF]
Kuldeep Dhama,Mahesh Mahendran,Ruchi Tiwari,Shambhu Dayal Singh,Deepak Kumar,Shoorvir Singh,Pradeep Mahadev Sawant
Veterinary Medicine International , 2011, DOI: 10.4061/2011/712369
Abstract: Tuberculosis, a List B disease of World Organization for Animal Health, caused by M. avium or M. genavense predominantly affects poultry and pet or captive birds. Clinical manifestations in birds include emaciation, depression and diarrhea along with marked atrophy of breast muscle. Unlike tuberculosis in animals and man, lesions in lungs are rare. Tubercular nodules can be seen in liver, spleen, intestine and bone marrow. Granulomatous lesion without calcification is a prominent feature. The disease is a rarity in organized poultry sector due to improved farm practices, but occurs in zoo aviaries. Molecular techniques like polymerase chain reaction combined with restriction fragment length polymorphism and gene probes aid in rapid identification and characterization of mycobacteria subspecies, and overcome disadvantages of conventional methods which are slow, labour intensive and may at times fail to produce precise results. M. avium subsp. avium with genotype IS901+ and IS1245+ causes infections in animals and human beings too. The bacterium causes sensitivity in cattle to the tuberculin test. The paper discusses in brief the M. avium infection in birds, its importance in a zoonotic perspective, and outlines conventional and novel strategies for its diagnosis, prevention and eradication in domestic/pet birds and humans alike. 1. Introduction Avian tuberculosis is one of the most important diseases that affect domestic and pet birds. Several mycobacterial species can be involved in the aetiology of avian tuberculosis. The disease is most often caused by Mycobacterium avium belonging to serotypes 1, 2, 3, and 6 (genotype IS901+ and IS1245+) and M. genavense [1–3]. Other species, such as M. intracellulare, M. scrofulaceum, M. fortuitum, M. tuberculosis, and M. bovis can also cause avian tuberculosis, but the incidences are rare [2, 4–6]. M. avium causes avian tuberculosis in probably all avian species, especially in waterfowl, galliformes, columbiformes, passerines, psittacines, raptors, and ratites [1, 7–10]. The disease has a worldwide distribution but is seen most frequently in the North Temperate Zone [11–14]. Susceptibility to disease varies from species to species. Hejlicek and Treml [15] broadly classified bird species into four groups according to their susceptibility to avian tuberculosis as highly susceptible: domestic fowl, sparrows, pheasants, and partridges; less susceptible: guinea fowl and domestic turkeys; moderately resistant: domestic goose and duck, highly resistant: the domestic pigeon. In any avian species, stress factors appear to
Biofilm formation by Mycobacterium avium isolates originating from humans, swine and birds
Tone Johansen, Angelika Agdestein, Ingrid Olsen, Sigrun Nilsen, Gudmund Holstad, Berit Dj?nne
BMC Microbiology , 2009, DOI: 10.1186/1471-2180-9-159
Abstract: Nine isolates from swine produced biofilm. There was a significant higher frequency of porcine isolates forming biofilm compared to human isolates. All isolates were previously characterised by IS1311- and IS1245-RFLP typing. The ability to form biofilm did not correlate with the RFLP-type, hsp65 sequevar, colony morphology or the presence of gene sequences related to GPL synthesis.The observed differences in biofilm forming abilities between porcine and human isolates raises questions regarding the importance of biofilm formation for infectious potential. The optimised method worked well for screening of multiple isolates.Mycobacterium avium includes the subspecies avium, silvaticum, paratuberculosis and hominissuis [1-3]. The former, M. avium subsp. avium causes tuberculosis in captive and free living birds [4], while M. avium subsp. hominissuis is an opportunistic environmental pathogen for humans and swine, and occasionally also for other mammals [1]. The most common forms of disease in humans are pulmonary disease, lymphadenitis and disseminated infection [5-7], while swine usually develop localised lymph node lesions [8]. Various molecular tools have been used to characterise isolates of M. avium, including restriction fragment length polymorphism (RFLP) [9], sequencing of the hsp65 gene [10] and multilocus sequence analysis (MLSA) [11]. In a previous study, we characterised M. avium isolates from birds, swine and humans in Norway by IS1311- and IS1245-RFLP typing. Our study demonstrated that transmission between animals and/or humans of identical isolates of M. avium is uncommon in Norway, and that transmission of M. avium from the environment to humans and animals is more likely [12]. The results are in accordance with other studies [13-15].M. avium has been found in soils and waters worldwide [5], and isolates with identical RFLP-profiles have been found in peat and human patients and in peat and swine, respectively [16,17]. Drinking water has also been sho
Detection of Mycobacterium avium subsp. paratuberculosis by a Direct In Situ PCR Method  [PDF]
Fernando Delgado,Diana Aguilar,Sergio Garbaccio,Gladys Francinelli,R. Hernández-Pando,María Isabel Romano
Veterinary Medicine International , 2011, DOI: 10.4061/2011/267102
Abstract: In situ detection of Mycobacterium avium subsp. paratuberculosis is useful for diagnosis and research of paratuberculosis. The aim of this paper was to detect this agent in formalin-fixed, paraffin-embedded tissue samples by a direct in situ PCR. The technique was performed on ileum or ileocaecal lymph node samples from 8 naturally infected cattle and 1 healthy calf, by using p89 and p92 primers for amplification of IS900 sequence. Moderate positive signal was detected in all positive samples and not in negative control, but tissues resulted were affected in many cases due to the enzymatic treatment and the high temperature exposition. Although the technique was useful for Map detection, the signal was lower than immunohistochemistry probably because of the fixation process. In one case, signal was higher, which might be due to the detection of spheroplasts. Thus, the described method should be recommended when others resulted negative or for spheroplasts detection. 1. Introduction Mycobacterium avium subsp. paratuberculosis (Map) is the causative agent of paratuberculosis (PTB), also called Johne’s disease. This affects cattle, sheep, and goats and produces losses in daily and beef production. Clinical features include diarrhea and loss of weight, and the main pathologic changes are granulomatous inflammation of the intestine and mesenteric lymph nodes [1]. Additionally, PTB is suspected to be related to Crohn’s disease (CD) in humans although this hypothesis is currently debated [2, 3]. Histopathology is used as a diagnostic method, but it is also a very important tool for researching PTB. Detection of Map in tissue samples increases the pathologic diagnosis and may be necessary when experimental infections are performed. Several techniques such as Ziehl Nielsen staining (ZN), immunohistochemistry (IHC), and in situ hybridization (ISH) were tested for detection of the agent [2, 4, 5], but their performances are different. ZN and IHC are easy to perform and have high sensitivity [4–6], but false negative can arise when infection was recent or bacilli were scanty. Besides, their specificity may be considered low since ZN can not differentiate among acid fast microorganisms and antigens shared by different mycobacteria may affect IHC performance. When both are compared, ZN is cheaper, but IHC may detect antigens of Map even when the bacillus was digested in the cytoplasm of macrophages. On the other hand, ISH is specific but more expensive, hard to perform, and its interpretation may be difficult because of the lower signal obtained [5]. However,
Clinical Evaluation of COBAS TaqMan PCR for the Detection of Mycobacterium tuberculosis and M. avium Complex  [PDF]
Satoshi Ikegame,Yoritake Sakoda,Nao Fujino,Kazuhito Taguchi,Masayuki Kawasaki,Akira Kajiki
Tuberculosis Research and Treatment , 2012, DOI: 10.1155/2012/170459
Abstract: A retrospective observational study was performed to determine the sensitivity and limitation of PCR test for the detection of Mycobacterium tuberculosis and M. avium complex. We obtained clinical specimens collected from the respiratory tract, cultured M. tuberculosis or M. avium complex, and performed PCR analysis. A total of 299 samples (M. tuberculosis, 177; M. avium, 35; M. intracellulare, 87) were analyzed by COBAS TaqMan PCR from April 2007 to March 2011. The PCR positivity rates were 50–55%, 70–100%, 88–98%, and 100% in smear-negative, smear 1+, 2+, and 3+ groups, respectively. The PCR positivity of tuberculosis in smear 1+ was 80.6%, which was statistically significantly ( ) lower than that of smear 2+ (97.3%). From January 2005 to March 2007, we collected an additional 138 samples (M. tuberculosis, 74; M. avium, 21; M. intracellulare, 43), which were analyzed by COBAS Amplicor PCR. The PCR positivity rates obtained using COBAS TaqMan PCR and COBAS Amplicor PCR were not significantly different. The sensitivity of PCR test for mycobacteria is not sufficient in case of smear 1+. Careful consideration must be given to the interpretation of negative PCR test results in smear 1+, because smear-positive tuberculosis is the criterion for isolation. 1. Introduction Polymerase chain reaction (PCR), which was invented by Kary Banks Mullis [1, 2], is widely used in basic and clinical medicine. Particularly in the field of clinical medicine, PCR plays an important role in the early diagnosis of infectious diseases [3], because PCR can detect as little as one copy of DNA fragment from a pathogenic organism. The utility of PCR has also been reported in the diagnosis of mycobacteriosis [4, 5], and PCR is widely used for the detection of Mycobacterium tuberculosis and M. avium complex (MAC) in Japan. On the other hand, a specimen with a positive mycobacterial smear and a negative M. tuberculosis PCR test may sometimes exhibit a positive M. tuberculosis culture result. Such false negative results are very dangerous, because they may lead to the release of patients that pose an infection control risk. We evaluated the reliability and limitation of PCR test for the detection of M. tuberculosis, M. avium, and M. intracellulare in relation to the clinical situation. We found out that PCR result is sometimes not reliable in smear 1+ case. 2. Methods 2.1. Study Subjects Clinical specimens collected from the respiratory tract (sputum or samples obtained using a bronchofiberscope (BF)) were analyzed from January 2005 to March 2011. M. tuberculosis, M. avium, or M.
Rapid detection of Mycobacterium avium subsp. paratuberculosis from cattle and zoo animals by Nested PCR
Joseph Erume, Joachim Spergser, Renate Rosengarten
African Health Sciences , 2001,
Abstract: Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis, a suspect causative agent of Crohns disease in man, is an emerging disease of international proportions affecting all ruminants. Early stage detection of Mycobacterium avium subsp. paratuberculosis infection would accelerate progress in control programmes. Despite new molecular approaches the standard diagnostic test for this disease is at present still the time consuming classic isolation procedure. Therefore, alternative diagnostic tests such as PCR, are needed for quick detection of infected animals. In this study, the conventional enrichment and isolation procedure and two IS900-based PCR methods for detection of Mycobactrium avium subsp. paratuberculosis in clinical samples from zoo animals and cattle were compared. A total number of 48 different clinical specimens obtained from animals suspected of having paratuberculosis were examined. The samples included faeces (n = 15) and organ tissues (n = 33). Of the faecal specimens two were identified as positive by nested PCR, whereas none was positive by single PCR or by culture. 28 organ specimens were found positive by culture. Mycobactrium avium subsp. paratuberculosis DNA was detected by nested PCR in 82% of the organ specimens identified positive by culture (23 samples) as opposed to 57% by single PCR (16 samples). Nested PCR also identified two positive samples that were not detected by either culture or single PCR. These findings show the great potential of nested PCR as a useful tool for the rapid diagnosis of paratuberculosis in animals. African Health Sciences 2001; 1(2): 83-89
Detection of Mycobacterium avium subsp. paratuberculosis in Cow Milk Using Culture and PCR methods  [cached]
Fathi, R.,,Sarkarati, F.,,Eslami, M.,,rezavand, B.
Archives of Razi Institute , 2011,
Abstract: Mycobacterium avium subspecies paratuberculosis (MAP) is the cause of John’s disease also calledparatuberculosis. This is economically one of the important infectious diseases in cattle and ruminanthusbandry. This disease is manifested as granulomatosis entrocolitis, lymphadenitis and inflammation locallymphatic vessels. The typical sign of this disease is progressive loss of weight. Considering the importanceof detection of this disease in this study, two methods, culture and PCR, were used for the identification ofthis microorganism. In this study 100 milk samples from apparently healthy cows and 100 milk samplesfrom cows that have been suspicious of John’s disease were taken from in Sarab, East Azarbaijan, Iran.Direct microscope observation after ziehl-neelsen staining was done. Then, bacterial culture on specificmedium was carried out, and finally, identification of Mycobacterium avium subsp. paratuberculosis wasexamined using PCR and specific primers. Using direct observation, culture and PCR analyses showed thatfrom 100 healthy cow milk samples, 8, 9 and 12 samples were positive MAP for each method respectively.The results of direct observation, culture and PCR analysis on affected cows were 15, 40 and 44, respectively. The results of this study showed that culture and PCR analyses methods are important in the identification of the causes of this disease. Therefore, considering the frequency of the disease in the studied region, either of those methods can be used in the microorganism identification.
Detection of Mycobacterium avium ss. Paratuberculosis in Blau Syndrome Tissues  [PDF]
C. Thomas Dow,Jay L. E. Ellingson
Autoimmune Diseases , 2010, DOI: 10.4061/2010/127692
Abstract: Background and Aim of the Work. Blau syndrome is an inherited granulomatous inflammatory disorder with clinical findings of uveitis, arthritis, and dermatitis. Although rare, Blau syndrome shares features with the more common diseases sarcoidosis and Crohn's disease. The clinical findings of Blau syndrome are indistinguishable from juvenile sarcoidosis; the mutations of Blau syndrome are on the same gene of chromosome 16 (CARD15) that confers susceptibility to Crohn's disease. The product of this gene is part of the innate immune system. Mycobacterium avium ss. paratuberculosis (MAP) is the putative cause of Crohn's disease and has been implicated as a causative agent of sarcoidosis. Methods. Archival tissues of individuals with Blau syndrome were tested for the presence of MAP. Results. DNA evidence of MAP was detected in all of the tissues. Conclusions. This article finds that MAP is present in Blau syndrome tissue and postulates that it has a causal role. The presence of MAP in Blau syndrome—an autosomal dominant, systemic inflammatory disease—connects genetic and environmental aspects of “autoimmune” disease. 1. Introduction Blau syndrome is familial juvenile systemic granulomatosis [1]. Although rare, Blau syndrome has been of interest in current medical literature because of the discovery that places its genetic defect on the same gene as one of the susceptibility genes for Crohn’s disease [2, 3]. Linkage studies have placed the gene on chromosome 16; originally referred to as the NOD2 gene, it is now known as the CARD15 gene [4]. The Blau syndrome susceptibility component of the CARD15 gene is at the nucleotide binding site domain [2, 5] while the Crohn’s susceptibility is at the N-terminal leucine-rich repeat domain [4, 6]. In addition to Crohn’s disease and Blau syndrome, mutations of the CARD15 gene have been linked to psoriatic arthritis [7]. The CARD15 gene is part of the ancestral innate immune system that senses and eliminates bacteria [8, 9], and is part of the newly recognized, larger CATERPILLER gene family which acts as sensors to detect pathogens which regulates inflammatory and apoptotic responses [10]. Blau syndrome is unique in that it is the only systemic granulomatous disease that has a recognized Mendelian pattern of inheritance: autosomal dominant [11]. The landmark progress associating this gene with systemic granulomatous disease has prompted studies of other granulomatous disease to look for a similar defect [3, 12]. While CARD15 defects confer susceptibility Crohn’s disease, Blau syndrome, and psoriatic arthritis [7] no
DETEKSI MYCOBACTERIUM AVIUM SUBSPECIES PARATUBERCULOSIS PADA SUSU FORMULA LANJUTAN DI BOGOR [Detection of Mycobacterium avium subspecies paratuberculosis Formula Milk in Bogor]  [cached]
Widagdo Sri Nugroho1,2),Mirnawati Sudarwanto3),Denny Widaya Lukman3),Rochman Naim3)
Jurnal Teknologi dan Industri Pangan , 2008,
Abstract: Mycobacterium avium subspecies paratuberculosis (MAP) becomes a public health concern in developed countries which is usually associated to Crohn’s disease (CD) in human. The disease shows similarities in clinical signs and pathology characteristic with John’s disease (JD) in ruminants which is infected by MAP. Researchers in Europe, USA, and Australia detected MAP in their dairy products and showed the relationship among MAP, CD, and JD. Meanwhile Indonesia imported milk and milk products from those countries to cover the national demand. This situation keeps MAP as potential-problem in national dairy herd and human health in the future. The aim of this study was to detect MAP in the formla milk for todler. Fifty samples from five established milk producers were taken on August 2006 at the supermarket in Bogor. Two seperate diagnostic methods were used parallel in this study i.e.: polymerase chain reaction method (PCR) with insertion sequence F 57 as the primer and the Mycobacterial Growth Indicator Tube (MGIT). Neither MAP grew in MGIT after 20 weeks of incubation period but 5 samples were found positive by nested PCR. Although there was no evidence weather MAP grew from the samples in this study, the comprehensive and sustainable studies on MAP should be carried out with more extensive and varied samples, as well as in human to provide data on MAP in Indonesia.
New PCR systems to confirm real-time PCR detection of Mycobacterium avium subsp. paratuberculosis
David Herthnek, G?ran B?lske
BMC Microbiology , 2006, DOI: 10.1186/1471-2180-6-87
Abstract: Our confirmatory PCR systems on IS900 were found sensitive and specific, only yielding weak false positive reactions in one strain for each system. The PCR system on F57 did not elicit any false positives and was only slightly less sensitive than our primary IS900-system. DNA from both naturally infected and spiked faeces that tested positive with our primary system could be confirmed with all new systems, except one low-level infected sample that tested negative with the F57 system.We recommend using the newly constructed DH3 PCR system on the F57 gene as the primary confirmatory test for PCR positives, but should it fail due to its lower sensitivity, the DH1 and DH2 PCR systems should be used.Paratuberculosis (Johne's disease) is caused by Mycobacterium avium subsp. paratuberculosis (MAP). It is a ubiquitous chronic enteric wasting disease of ruminants, though in Sweden the disease is rare or absent, thanks to successful control measures in the past. It is regarded as an exotic disease and falls under the Swedish Epizootic Act, which means that in an event of an outbreak, measures must be taken promptly to combat the disease and to trace the origin of the outbreak [1,2]. When a positive case is identified, consequences for the farmer are grave and it is usually deemed necessary to slaughter the whole herd.In the Swedish Paratuberculosis Control Program and in most of the Swedish surveillances undertaken to monitor freedom from paratuberculosis, detection is based on culture. During the culture procedure, suspected colonies are picked and identified as MAP by PCR. Other characteristics of the colony isolate act to confirm the identification made with PCR, namely acid-fast staining (acid-fast bacilli), growth characteristics (small, slow-growing) and dependence on mycobactin. The PCR methods generally used to identify and detect MAP are based on IS900, an insertion sequence considered specific for MAP [3-6]. IS900 is a 1,451 bp segment that lacks inverted terminal r
Detection of Mycobacterium avium subsp. paratuberculosis in asymptomatic bovines by IS900 Polymerase Chain Reaction
Remya Raveendran,Priya P.M.,Koshy John,Krishnan Nair G
Veterinary World , 2011,
Abstract: Faecal samples were collected from 58 asymptomatic bovines and after DNA extraction IS900 Polymerase Chain Reaction (IS900 PCR) was performed to detect Mycobacterium avium subsp. paratuberculosis (MAP). Ten samples (17.24 %) were positive for MAP. The results indicated that the IS900 PCR assay can be used for the early diagnosis of bovine paratuberculosis. [Vet. World 2011; 4(6.000): 248-249]
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