Cord factor detection and macroscopic evaluation of mycobacterial colonies: an efficient combined screening test for the presumptive identification of Mycobacterium tuberculosis complex on solid media

Simeão, Fernanda Cristina dos Santos; Chimara, Érica; Oliveira, Rosângela Siqueira de; Yamauchi, Jonas Umeoka; Latrilha, Fábio Oliveira; Telles, María Alice da Silva

doi:10.1590/s1806-37132009001200008

Cited by 10 publications

(6 citation statements)

References 10 publications

(1 reference statement)

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“…Simeão et al recommended "the combined screening test to rapidly identify M. tuberculosis in resource-poor settings and in less well-equipped laboratories while awaiting definite identification by molecular or biochemical methods." (1) I agree that the new alternative test might be effective in the diagnosis. However, there are some concerns.…”

Section: To the Editormentioning

confidence: 87%

“…I read the report on the alternative test for the presumptive identification of Mycobacterium tuberculosis complex with a great interest. (1) . Simeão et al recommended "the combined screening test to rapidly identify M. tuberculosis in resource-poor settings and in less well-equipped laboratories while awaiting definite identification by molecular or biochemical methods."…”

Section: To the Editormentioning

confidence: 99%

See 1 more Smart Citation

New alternative test for Mycobacterium tuberculosis complex

Wiwanitkit

2010

J. bras. pneumol.

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Section: To the Editormentioning

confidence: 87%

Section: To the Editormentioning

confidence: 99%

New alternative test for Mycobacterium tuberculosis complex

Wiwanitkit

2010

J. bras. pneumol.

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“…Implementation of the mpt64 real-time PCR assay in the TB diagnosis routine - From May 2011 to July 2012, 1,520 primary isolates of mycobacteria in liquid or on solid media from SP, Brazil, were included in the study. First, a presumptive identification according to micro- and macroscopic characteristics of the isolates was performed to classify these samples as MTC or non-tuberculous mycobacteria (NTM) isolates as described elsewhere ( Monteiro et al 2003 , Coelho et al 2007 , Simeão et al 2009 ) (Figure).…”

Section: Methodsmentioning

confidence: 99%

Performance of an in-house real-time polymerase chain reaction for identification of Mycobacterium tuberculosis isolates in laboratory routine diagnosis from a high burden setting

Gallo

Pinhata

Chimara

et al. 2016

Mem. Inst. Oswaldo Cruz

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Brazil is one of the high burden countries for tuberculosis, and a rapid diagnosis is essential for effective control of the disease. In the present study, an in-house real-time polymerase chain reaction (PCR) assay targeting the mpt64 gene for identification of Mycobacterium tuberculosis complex isolates was evaluated under routine diagnosis conditions in a reference laboratory. From May 2011 to July 2012, 1,520 isolates of mycobacteria were prospectively submitted for phenotypic and/or PRA-hsp65 identification and to real-time PCR. The mpt64 real-time PCR showed 99.7% sensitivity and 96% specificity and detected 79.4% of the cases missed by phenotypic and PRA-hsp65 identification. The in-house real-time PCR assay showed high sensitivity and specificity and was successfully implemented in the routine diagnosis of tuberculosis in a reference laboratory from a high burden setting.

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“…At Instituto Adolfo Lutz, the isolates were first evaluated according to the growth characteristics of the cultures so they could be presumptively identified as MTBC or NTM [11,12]. Colonies of MTBC on solid media have a dry, cream-coloured, wrinkled appearance [12], while the growth of MTBC in liquid media is usually limpid with the presence of flocculation [11]. NTM colonies on solid media can be cream-coloured or pigmented, smooth, moist or wrinkled [12].…”

Section: Laboratory Proceduresmentioning

confidence: 99%

“…Colonies of MTBC on solid media have a dry, cream-coloured, wrinkled appearance [12], while the growth of MTBC in liquid media is usually limpid with the presence of flocculation [11]. NTM colonies on solid media can be cream-coloured or pigmented, smooth, moist or wrinkled [12]. In liquid media, they show turbid and/or pigmented growth but can also be flocculated [11].…”

Section: Laboratory Proceduresmentioning

confidence: 99%

Non-tuberculous mycobacteria hybridisation profiles in the GenoType MTBDRplus assay: experience from a diagnostic routine of a high-throughput laboratory

Oliveira,

Chimara,

Brandão

et al. 2024

Journal of Medical Microbiology

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Introduction. Disease caused by non-tuberculous mycobacteria (NTM) is an emergent problem. Because NTM pulmonary disease and tuberculosis (TB) have similar clinical presentations, many cases of NTM may be misdiagnosed as TB before laboratory identification of the NTM species. Hypothesis/Gap Statement. Clinical laboratories should always perform differentiation between Mycobacterium tuberculosis complex (MTBC) and NTM to guide patients' correct treatment. Aim. To describe the characteristics and to identify mycobacterial isolates presumptively classified as MTBC by macroscopic characteristics in culture media that tested negative in GenoType MTBDRplus. Methodology. All cultures from February 2019 to December 2021 showing MTBC macroscopic characteristics were processed by GenoType MTBDRplus. MTBC-negative cultures underwent species identification by immunochromatography, line probe assays and PRA-hsp65. Patients’ data were obtained from Brazilian surveillance systems. Results. Only 479 (3.1%) of 15 696 isolates presumptively identified as MTBC were not confirmed by GenoType MTBDRplus and were then subjected to identification. A total of 344 isolates were shown to be NTM, of which 309 (64.5%) and 35 (7.3%) were identified to the species and genus levels, respectively. Of the 204 NTM isolates with MTBC characteristics, the most frequent species were M. fortuitum (n=52, 25.5%), M. abscessus complex (MABC; n=27, 13.2%) and M. avium complex (MAC; n=26, 12.7%). Regarding the GenoType MTBDRplus results from NTM isolates, there were diverse hybridisation profiles with rpoB gene’s different wild-type (WT) probes. Seventy-six (16.1%) of the 473 patients were classified as having NTM disease, the most frequent being MAC (n=15, 19.7%), MABC (n=13, 17.1%), M. kansasii (n=10, 13.2%) and M. fortuitum (n=6, 7.9%). Conclusion. Because the signs and symptoms of pulmonary TB are similar to those of pulmonary mycobacteriosis and treatment regimens for TB and NTM are different, identifying the disease-causing species is paramount to indicate the correct management. Thus, in the laboratory routine, when an isolate presumptively classified as MTBC is MTBC-negative, it is still essential to perform subsequent identification.

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Cord factor detection and macroscopic evaluation of mycobacterial colonies: an efficient combined screening test for the presumptive identification of Mycobacterium tuberculosis complex on solid media

Cited by 10 publications

References 10 publications

New alternative test for Mycobacterium tuberculosis complex

New alternative test for Mycobacterium tuberculosis complex

Performance of an in-house real-time polymerase chain reaction for identification of Mycobacterium tuberculosis isolates in laboratory routine diagnosis from a high burden setting

Non-tuberculous mycobacteria hybridisation profiles in the GenoType MTBDRplus assay: experience from a diagnostic routine of a high-throughput laboratory

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