Objective: To genetically characterize Clostridium perfringens isolates for association of pathologic type with various diseases.
Design: Prospective study.
Sample population: 2,659 C perfringens isolates from various nonhuman animals species, human beings, and foods.
Procedure: Colony hybridization with DNA probes for 7 toxin (alpha, beta, epsilon, iota (subunits a and b), theta, mu, and enterotoxin) genes and 1 sialidase gene were performed to group the isolates by pathologic type.
Results: Enterotoxin-negative type-A isolates were the most common (2,575/2,659), were isolated from all sources, and were separated into 5 pathologic types. In cattle and horses with enterotoxemia, essentially only these pathologic types were identified. The enterotoxin-negative isolates of types C or D each had a single pathologic type. Type-C isolates were isolated only from swine with necrotic enteritis and type-D isolates from small ruminants with enterotoxemia, except that 1 type-D isolate was also found from a healthy fish. Type-B or -E isolates were not found. Among the 47 enterotoxin-positive isolates, 5 isolates from sheep or deer were type D and the other 42 were type A. These 42 isolates were grouped into 3 pathologic types: 1 type was isolated from samples of almost all origins, but the other 2 types were found in only 5 fish, 4 human beings, and 1 dog.
Conclusions and clinical relevance: Genetic characterization of these isolates allowed identification of 11 different pathologic types. This approach may be useful in molecular diagnosis and prophylaxis of clostridial disease.