Gram-positive spore-forming bacilli were extracted in anoxic environment from the patient’s wound contaminated with soil. Cultivation on a blood-glucose agar resulted in growth of the colonies surrounded with hemolysis zone. What agent was extracted from the wound?

Answer options

1. Clostridium botulinum
2. Clostridium perfringens
3. Staphylococcus aureus
4. Pseudomonas aeruginosa
5. Escherichia coli

Explanation

Gram-positive spore-forming bacilli were extracted in anoxic environment from the patient’s wound contaminated with soil. Cultivation on a blood-glucose agar resulted in growth of the colonies surrounded with hemolysis zone. What agent was extracted from the wound?Clostridium perfringens Colony morphology on Sheep Blood agar:Large, smooth, regular, convex, slightly opaque, flat radially striated transparent border - Can be rough flat vine leaf colonyTypical Double zone of hemolysis:Zone of complete hemolysis due to Beta hemolytic Theta toxin (one of the minor toxins)Wider zone of partial hemolysis caused by an Alpha hemolytic Alpha toxin (one of the major toxins)