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Year : 2005  |  Volume : 23  |  Issue : 4  |  Page : 272--273

Evaluation of paraffin baiting technique for rapid isolation of atypical mycobacteria

H Kaur, A Oberoi 
 Department of Microbiology, Christian medical College and Hospital, Ludhiana 141 008, Punjab, India

Correspondence Address:
A Oberoi
Department of Microbiology, Christian medical College and Hospital, Ludhiana 141 008, Punjab
India

How to cite this article:
Kaur H, Oberoi A. Evaluation of paraffin baiting technique for rapid isolation of atypical mycobacteria.Indian J Med Microbiol 2005;23:272-273

How to cite this URL:
Kaur H, Oberoi A. Evaluation of paraffin baiting technique for rapid isolation of atypical mycobacteria. Indian J Med Microbiol [serial online] 2005 [cited 2020 Oct 31 ];23:272-273
Available from: https://www.ijmm.org/text.asp?2005/23/4/272/17087

Full Text

Dear Editor,

Atypical mycobacteria (AM) are widely distributed in nature and can cause pulmonary disease simulating tuberculosis. Paraffin baiting was developed for isolating organisms like Nocardia and mycobacteria from soil,[1] because of their ability to utilize paraffin wax as the sole source of carbon. The baiting was accomplished by growing the organisms in a medium lacking any carbon source into which were dipped glass rods coated with paraffin wax. Paraffin baiting technique by using paraffin coated glass slide instead of glass rod was evaluated, by using stock cultures of 42 isolates positive for acid fast bacilli by automated Bactec system, one Mtb H37RV strain (negative control) and one Nocardia asteroides (positive control). The stock cultures were grown in 5mL each of 7H9 medium with oleic acid, albumin, dextrose, catalase and incubated at 37[0]C for 7 days or till the turbidity matched that of McFarland's no.1 standard. Then 0.5mL of the growth was inoculated into 4.5mL of sterile Czapek broth into which were dipped sterile paraffin coated slides, incubated at 37oC and checked daily for growth. The growth observed on the slide, either in the form of discrete colonies or confluent growth, was subjected to Ziehl Neelsen's staining technique. Results of paraffin baiting technique in different clinical specimens are shown in the table.

Paraffin baiting technique has been used for isolation and drug susceptibility testing of M.avium intracellulare from blood culture by modified broth dilutions assay[2],[3] and growth on slides can even be used for DNA extraction for molecular studies.[2] Therefore, it can be concluded from the study that paraffin baiting technique provides an inexpensive, rapid and simple alternative for isolation, cultivation, speciation, drug susceptibility testing of atypical mycobacteria with lesser risk of contamination with other human pathogens and can be used for isolating atypical mycobacteria from specimens that may contain variety of other organisms .

References

1Gordon RE, Hagan WA. A study of some acid fast actniomycetes from soil with special reference to pathogenecity for animals. J Infect Dis 1936; 59 :200.
2Ollar RA, Dale JW, Felder MS, Favate A. The use of paraffin wax metabolism in the speciation of Mycobacterium avium-intracellulare. Tubercle 1990; 71 :23.
3Ollar RA, Brown S, Dale JW, Felder MS, Brown IN, Edwards FF, et al. A modified broth dilution assay for antibiotic sensitivity testing of Mycobacterium avium intracellulare using paraffin slide culture. Tubercle 1991; 72 :198-205