Corynebacterum other than diphtheriae carrying toxin:
**Core Concept**
Corynebacterium species can produce various toxins, but the toxin associated with diphtheria is unique to Corynebacterium diphtheriae. Other Corynebacterium species can carry other types of toxins.
**Why the Correct Answer is Right**
Corynebacterium ulcerans and Corynebacterium pseudotuberculosis are known to produce toxins that cause ulcers and lymphadenitis, respectively. These toxins are different from the diphtheria toxin produced by Corynebacterium diphtheriae. The toxin production in these species is due to the presence of a bacteriophage that carries the toxin gene.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because Corynebacterium diphtheriae is the primary species associated with diphtheria toxin production.
**Option B:** Incorrect because Corynebacterium pseudotuberculosis is known to produce a toxin that causes lymphadenitis, but it is not the same as the diphtheria toxin.
**Option D:** Incorrect because there is no well-documented toxin-producing Corynebacterium species associated with this option.
**Clinical Pearl / High-Yield Fact**
When suspecting a Corynebacterium infection, it is essential to identify the species and determine if it is producing a toxin. This can be crucial in guiding treatment and preventing complications.
**Correct Answer:** C. Corynebacterium ulcerans