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Effects of isoniazid on viability, cell morphologies and acid fastness properties of Mycobacterium avium NCTC 8559 during the growth cycle

Mohamad S, Ibrahim P, Wahab HA

Chemotherapy, 2007;53(4):263-6.
PMID: 17595540

Our previous study demonstrated that the effects of isoniazid (INH) on Mycobacterium tuberculosis at the cellular level varied according to the growth phases. In this study, the variations in the INH action on M. avium strain NCTC 8559 are reported. M. avium cells grown on Middlebrook 7H10 agar were harvested at different stages of their growth cycle, exposed to the minimum inhibitory concentration of INH, stained with acid-fast staining for morphological changes and acid fastness properties, and the number of colonies were evaluated for viability studies. The study demonstrated that M. avium NCTC 8559 cells at the initial and fragmentation stages of the growth cycle were most susceptible to INH.

Matched MeSH terms: Mycobacterium avium/cytology; Mycobacterium avium/drug effects*; Mycobacterium avium/growth & development
Fulltext Evaluation of six decontamination procedures for isolation of Mycobacterium avium complex from avian feces

Sattar A, Zakaria Z, Abu J, Aziz SA, Gabriel RP

PLoS One, 2018;13(8):e0202034.
PMID: 30096205 DOI: 10.1371/journal.pone.0202034

Culture is considered the gold standard for definitive diagnosis of mycobacterial infections. However, consensus about the most suitable culture procedure for isolation of nontuberculous mycobacteria is lacking. The study compared the recoveries of mycobacteria after decontamination of spiked and fresh avian feces with 4% sodium hydroxide (NaOH), 12% sulfuric acid (H2SO4), or 1% cetylperidinium chloride (CPC), with and without mixture of three antibiotics, namely vancomycin (VAN, 100 μg/ml), nalidixic acid (NAL, 100 μg/ml), and amphotericin B (AMB, 100 μg/ml). The antibiotic mixture was referred to as VNA. Decontamination procedures were evaluated using two (n = 2) avian fecal samples spiked with 106, 104, and 102 CFU/ml of Mycobacterium avium subsp. avium (ATCC 15769) and fresh avian feces (n = 42). M. avium subsp. avium was detected on the culture media from spiked samples (106 and 104 CFU/ml) decontaminated with NaOH, NaOH-VNA, H2SO4, and H2SO4 -VNA for 2-6 weeks. These bacteria were detected in 2-4 weeks when using CPC and CPC-VNA. M. avium subsp. avium cannot be isolated on culture media from spiked samples (102 CFU/ml) decontaminated with any decontaminating agent. Two mycobacterial isolates, namely, Mycobacterium terrae and M. engbaekii, were isolated from field samples decontaminated with NaOH and CPC-VNA. With regard to the contamination rate, the use of CPC-VNA showed lower contamination rates (5.5% and 19.0%) from spiked and field samples than those of the other methods (NaOH: 22.2% and 59.5%, NaOH-VNA: 16.7% and 21.4%, H2SO4: 11.1% and 40.5%, H2SO4-VNA: 5.5% and 21.4%, and CPC: 66.7% and 50%). In conclusion, the decontamination of fecal samples following a two-step procedure with 1% CPC and VNA can ensure high recovery rate of many mycobacteria with the lowest contamination in cultures.

Matched MeSH terms: Mycobacterium avium Complex/drug effects; Mycobacterium avium Complex/genetics; Mycobacterium avium Complex/isolation & purification*; Mycobacterium avium-intracellulare Infection/microbiology*
Fulltext Primary Mycobacterium avium Enteritis in a Patient Infected with Human Immunodeficiency Virus

Chang CY

Rev Soc Bras Med Trop, 2021;54:e03342021.
PMID: 34431951 DOI: 10.1590/0037-8682-0334-2021
Matched MeSH terms: Mycobacterium avium
Rice bodies in the wrist joint

Sulaiman H, Atiya N, Loi KW, Ng KP

Eur J Intern Med, 2016 Nov;35:e7-e8.
PMID: 27498273 DOI: 10.1016/j.ejim.2016.07.014
Matched MeSH terms: Mycobacterium avium Complex/isolation & purification*; Mycobacterium avium-intracellulare Infection/drug therapy
Mycobacterium avium subsp. paratuberculosis is not discerned in diabetes mellitus patients in Hyderabad, India

Rani PS, Doddam SN, Agrawal S, Hasnain SE, Sechi LA, Kumar A, et al.

Int J Med Microbiol, 2014 Jul;304(5-6):620-5.
PMID: 24863528 DOI: 10.1016/j.ijmm.2014.04.010

Mycobacterium avium ssp. paratuberculosis (MAP) is an obligate intracellular pathogen. It causes chronic intestinal inflammation in ruminants known as Johne's disease and is associated with human Crohn's disease. Furthermore, association of MAP with other autoimmune diseases, such as type-1 diabetes, has been established in patients from Sardinia (Italy) which is a MAP endemic and genetically isolated region. Due to largest livestock population and consequently high MAP prevalence amidst a very high diabetes incidence in India, we sought to test this association on a limited number of patient samples from Hyderabad. Our results of ELISA with MAP lysate and MAP-specific protein MAP3738c as well as PCR/real-time PCR of MAP-specific sequences IS900 and/or f57 indicated that, in contrast to Sardinian diabetic patients, MAP infection in blood is not discerned in diabetic patients in Hyderabad. The association of a mycobacterial trigger with diabetes therefore could well be a population-specific phenomenon, highly dependent on genetic repertoire and the environment of susceptible populations. However, a larger study is needed in order to confirm this.

Matched MeSH terms: Mycobacterium avium subsp. paratuberculosis/isolation & purification*
Fulltext Effect of Macrolide Prophylactic Therapy on AIDS-Defining Conditions and HIV-Associated Mortality

Pasayan MKU, S Mationg ML, Boettiger D, Lam W, Zhang F, Ku SW, et al.

J Acquir Immune Defic Syndr, 2019 04 01;80(4):436-443.
PMID: 30550488 DOI: 10.1097/QAI.0000000000001933

BACKGROUND: Mycobacterium avium complex prophylaxis is recommended for patients with advanced HIV infection. With the decrease in incidence of disseminated Mycobacterium avium complex infection and the availability of antiretroviral therapy (ART), the benefits of macrolide prophylaxis were investigated. This study examined the impact of macrolide prophylaxis on AIDS-defining conditions and HIV-associated mortality in a cohort of HIV-infected patients on ART.
METHODS: Patients from TREAT Asia HIV Observational Database (September 2015 data transfer) aged 18 years and older with a CD4 count <50 cells/mm at ART initiation were included. The effect of macrolide prophylaxis on HIV-associated mortality or AIDS-defining conditions (as a combined outcome) and HIV-associated mortality alone were evaluated using competing risk regression. Sensitivity analysis was conducted in patients with a CD4 <100 cells/mm at ART initiation.
RESULTS: Of 1345 eligible patients, 10.6% received macrolide prophylaxis. The rate of the combined outcome was 7.35 [95% confidence interval (CI): 6.04 to 8.95] per 100 patient-years, whereas the rate of HIV-associated mortality was 3.14 (95% CI: 2.35 to 4.19) per 100 patient-years. Macrolide use was associated with a significantly decreased risk of HIV-associated mortality (hazard ratio 0.10, 95% CI: 0.01 to 0.80, P = 0.031) but not with the combined outcome (hazard ratio 0.86, 95% CI: 0.32 to 2.229, P = 0.764). Sensitivity analyses showed consistent results among patients with a CD4 <100 cells/mm at ART initiation.
CONCLUSIONS: Macrolide prophylaxis is associated with improved survival among Asian HIV-infected patients with low CD4 cell counts and on ART. This study suggests the increased usage and coverage of macrolide prophylaxis among people living with HIV in Asia.

Matched MeSH terms: Mycobacterium avium Complex/drug effects*; Mycobacterium avium-intracellulare Infection/drug therapy; Mycobacterium avium-intracellulare Infection/prevention & control*
Fulltext Genome-wide association study of susceptibility to infection by Mycobacterium avium subspecies paratuberculosis in Holstein cattle

Alpay F, Zare Y, Kamalludin MH, Huang X, Shi X, Shook GE, et al.

PLoS One, 2014;9(12):e111704.
PMID: 25473852 DOI: 10.1371/journal.pone.0111704

Paratuberculosis, or Johne's disease, is a chronic, granulomatous, gastrointestinal tract disease of cattle and other ruminants caused by the bacterium Mycobacterium avium, subspecies paratuberculosis (MAP). Control of Johne's disease is based on programs of testing and culling animals positive for infection with MAP while concurrently modifying management to reduce the likelihood of infection. The current study is motivated by the hypothesis that genetic variation in host susceptibility to MAP infection can be dissected and quantifiable associations with genetic markers identified. For this purpose, a case-control, genome-wide association study was conducted using US Holstein cattle phenotyped for MAP infection using a serum ELISA and/or fecal culture test. Cases included cows positive for either serum ELISA, fecal culture or both. Controls consisted of animals negative for the serum ELISA test or both serum ELISA and fecal culture when both were available. Controls were matched by herd and proximal birth date with cases. A total of 856 cows (451 cases and 405 controls) were used in initial discovery analyses, and an additional 263 cows (159 cases and 104 controls) from the same herds were used as a validation data set. Data were analyzed in a single marker analysis controlling for relatedness of individuals (GRAMMAR-GC) and also in a Bayesian analysis in which multiple marker effects were estimated simultaneously (GenSel). For the latter, effects of non-overlapping 1 Mb marker windows across the genome were estimated. Results from the two discovery analyses were generally concordant; however, discovery results were generally not well supported in analysis of the validation data set. A combined analysis of discovery and validation data sets provided strongest support for SNPs and 1 Mb windows on chromosomes 1, 2, 6, 7, 17 and 29.

Matched MeSH terms: Mycobacterium avium subsp. paratuberculosis/genetics*
Serum antigen 85 levels in adjunct testing for active mycobacterial infections in orangutans

Kilbourn AM, Godfrey HP, Cook RA, Calle PP, Bosi EJ, Bentley-Hibbert SI, et al.

J. Wildl. Dis., 2001 Jan;37(1):65-71.
PMID: 11272506

Diagnosis of active mycobacterial disease in orangutans (Pongo pygmaeus) has been impeded by high levels of non-specific intradermal skin test reactivity to mycobacterial antigens. This may be due in part to cross reactivity between antigens, tuberculin concentrations used or other species-specific factors. Antigen 85 (Ag85) complex proteins are major secretory products of actively growing mycobacteria, and measurement of serum Ag85 could provide a method for determining active mycobacterial infections that was not dependent on host immunity. Serum Ag85 was measured by dot-immunobinding assay using monoclonal anti-Ag85, purified Ag85 standard and enhanced chemiluminescence technology in coded serum samples from 14 captive orangutans from a zoo in Colorado, 15 semi-captive orangutans in Malaysia, and 19 free-ranging wild orangutans in Malaysia. Orangutans from Colorado (USA) were culture negative for Mycobacterium tuberculosis and M. avium, although all had laboratory suspicion or evidence of mycobacterial infection; median serum Ag85 was 10 microU/ml (range, <0.25-630 microU/ml). Of the semi-captive orangutans, six were skin test reactive and two were culture positive for M. avium on necropsy. Median serum Ag85 for this group was 1,880 microU/ml (0.75-7,000 microU/ml), significantly higher than that of Colorado zoo or free-ranging Malaysian orangutans. Median serum Ag85 in the latter group was 125 microU/ml (range, 0.75-2,500 microU/ml). These data suggest that suggest that additional studies using more specific reagents and more samples from animals of known status are appropriate.

Matched MeSH terms: Mycobacterium avium/isolation & purification