Indian Journal of Medical Microbiology Home 

CORRESPONDENCE
[Download PDF]
Year : 2004  |  Volume : 22  |  Issue : 3  |  Page : 198-

Differential filtration on non-selective medium: Better method for isolation of c.upsaliensis and other campylobacters

A De, S Pinjarkar, M Mathur 
 Department of Microbiology, LTM Medical College and Hospital, Sion, Mumbai - 400 022, India

Correspondence Address:
A De
Department of Microbiology, LTM Medical College and Hospital, Sion, Mumbai - 400 022
India

How to cite this article:
De A, Pinjarkar S, Mathur M. Differential filtration on non-selective medium: Better method for isolation of c.upsaliensis and other campylobacters.Indian J Med Microbiol 2004;22:198-198

How to cite this URL:
De A, Pinjarkar S, Mathur M. Differential filtration on non-selective medium: Better method for isolation of c.upsaliensis and other campylobacters. Indian J Med Microbiol [serial online] 2004 [cited 2020 Nov 25 ];22:198-198
Available from: https://www.ijmm.org/text.asp?2004/22/3/198/11222

Full Text

Dear Editor,

Numerous selective media containing several antibiotics as inhibitory agents have been described for excellent recovery of Campylobacter jejuni, C.coli and C.lari from diarrhoeal stools.[1] But these media are unable to recover the catalase negative or weak positive campylobacters, e.g., C.upsaliensis, C.fetus, C.concisus etc., which have also been implicated in causing gastrointestinal disorders.[2] The differential filtration on a non-selective medium like brucella blood agar is most efficient for isolation of other campylobacters except C.jejuni and C.coli.[2],[3]

In a preliminary study, 50 stool samples from cases of acute gastroenteritis were taken. Direct plating was done on two modified charcoal cefoperazone deoxycholate agar (mCCDA) plates - one incubated at 37C and the other at 42C in microaerophilic atmosphere for 48 hours. For differential filtration, a membrane filter of pore diameter of 0.45m was applied to the surface of Brucella agar plate and spot inoculated with a faecal suspension. The filter paper was removed after 30 minutes and the plate was incubated at 37C in a microaerophilic atmosphere for 48 hours.[3] The suspected colonies on both the plates were identified by standard laboratory techniques.[1]

The rate of isolation of campylobacters rose from 14 to 16%, after combining both the methods. C.upsaliensis did not grow on mCCDA and it was recovered by filtration method only. Studies by McClurg et al and Lastovica et al have reported rise in rate of isolation of campylobacters from 9.7 to 11.8% and from 7.1 to 21.8% respectively, by combining both methods.[2],[4] Therefore, the differential filtration and plating on non-selective medium for detection of campylobacters from diarrhoeal stools should be included as an additional algorithm to direct plating on selective medium, for identification of campylobacters other than C.jejuni and C.coli.

References

1Curved gram negative bacilli and oxidase positive fermenters: Campylobacteriaceae and Vibrionaceae. Chapter 6. In: Color Atlas and Textbook of Diagnostic Microbiology, 5th ed. Koneman EW, Allen SD, Janda WM, Schreckenberger PC, Winn Jr. WC, Eds. (Lippincott, Philadelphia) 1997;321.
2McClurg KR, McClurg RB, Moore JE, Dooley JSG. Efficient isolation of Campylobacter from stools: What are we missing? J Clin Pathol 2002;55:239-240.
3Albert MJ, Tee W, Leach AS, Asche V, Penner JL. Comparison of a blood-free medium and a filtration technique for the isolation of Campylobacter spp. from diarrhoeal stools of hospitalized patients in Central Australia. J Med Microbiol 1992;37:176-179.
4Lastovica AJ, LeRoux E. Efficient isolation of Campylobacter upsaliensis from stools. J Clin Microbiol 2000;39:4222-4223.