Use of reducing agents for the aerobic growth of Campylobacter jejuni

Objective:To produce a technique for the growth of Campylobacter jejuni in aerobic condition Methods:Different combinations of reducing agents were tested in brucella broth and the growth turbidity was compared with tubes containing normal broth only.Microaerophilic environment was also provided in a petri plate seeded with Campylobacter culture by pouring 3 different concentrations（10%,5%and 2.5%） of five reducing agents along with bacto-agar in the lid which was used to cover and seal the culture plate.Six reducing agents were also added in broth in concentration of 0.25 mg/mL of each with different combinations.Results:In lid agar technique,Campylobacter jejuni growth appeared in all three concentrations of reducing agents, that is 10%,5%and 2.5%after 24 hours of incubation but the best results were observed in 10% concentration.The colonial and morphological characters were not affected when the organisms were grown by this technique.Conclusions:It was found that reducing agents enhance the growth of C.jejuni/coli.In combination of FeSO4,Na2CO3 with H3BO3 worked as ideal mixture for the aerobic growth of Campylobacter.This technique is more economical as compared to commercially available media in the market and can be used for the oral facultative and microaerophilic bacterial growth in laboratory.

Tuberculosis:an experience from Mycobacterium smears and culture analysis

Objective:Simple tests like direct smear of the acid fast bacilli(AFB) and Mycobacterium culture could assist the diagnosis of tuberculosis.This study is aimed at reviewing the outcome of smears,culture results and contamination rate among specimens requested for AFB smear and Mycobacterium culture.Methods:Retrospective laboratory data analysis requesting for Mycobacterium culture from January 2005 till December 2006 was done in a tertiary teaching hospital of Universiti Sains Malaysia,Kubang Kerian,Kelantan,Malaysia.Results: Four hundred and sixty seven(36.6%) isolates grew from 1 277 specimens.Of these isolates,314 (67.2%) grew Mycobacterium tuberculosis,23(4.9%) grew Mycobacterium other than tuberculosis and 38 (8.1%) grew contaminants.Among the M.tuberculosis cultures,165(52.5%) had growth of more than 100 confluent colonies,whereas 39 cultures(12.4%) had growth of less than 19 colonies.Direct smear for AFB among smear positive cases showed presence of more than 50 bacilli/line in 231(49.5%) cases and smear negative cases accounted for 63(13.5%).Among smear positive cases,291(94.5%) cultures grew Mycobacterium species and another 17(5.5%) cultures grew contaminants.In smear negative cases,32(62.7%) cultures grew Mycobacterium species and 19(37.3%) cultures grew contaminants.Conclusion:The results from data analysis of the Mycobacterium cultures should be critically utilized in order to review the laboratory performance and to improve its services in the future.Some of the data is also useful to the administrators of the hospital in terms of estimating the risk of occupational hazard faced by the health care workers.