Tissue and fluid cultures and Gram stain of fluid to test for Clostridium bacteria can be done. Blood cultures can be done to determine the bacteria causing the infection.

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  This strip of API® wells was inoculated with Clostridium perfringens. From Public Health Image Library (PHIL). ^[1]
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  Clostridium perfringens colonies cultured on a half-antitoxin plate. From Public Health Image Library (PHIL). ^[1]
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  F. mortiferum and C. perfringens, with E. coli and P. vulgaris inhibited, grown on 48hr PEA agar. From Public Health Image Library (PHIL). ^[1]
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  This MacConkey plate grew colonies of Escherichia coli, Fusobacterium mortiferum, P. vulgaris, but not C. perfringens. From Public Health Image Library (PHIL). ^[1]
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  This culture dish grew E. coli, F. mortiferum, P. vulgaris, and C. perfringens bacterial colonies. From Public Health Image Library (PHIL). ^[1]
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  Photograph depicts a colony of Clostridium sp. Gram-positive bacteria, which had been grown on a 4% blood agar plate (BAP) over a 48 hour time period. From Public Health Image Library (PHIL). ^[1]
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  Image depicts a Minitek® (BD Biosciences) anaerobe identification kit, used to identify specific bacterial species based on their microchemical behavior. All the wells except for the four empty wells in row four had been inoculated with Gram-positive Clostridium perfringens bacteria. From Public Health Image Library (PHIL). ^[1]