Corynebacterium minutissimum causes –
**Core Concept**
Corynebacterium minutissimum is a gram-positive, rod-shaped bacterium that is a common cause of erythrasma, a type of superficial skin infection. Erythrasma is characterized by well-demarcated, brownish-red patches, particularly in the intertriginous areas.
**Why the Correct Answer is Right**
Corynebacterium minutissimum produces porphyrins, which are responsible for the characteristic coloration of erythrasma lesions. The bacteria thrive in warm, humid environments, such as the skin folds, and can cause inflammation and hyperpigmentation. The infection is typically self-limiting but can be treated with topical antibiotics or antifungals.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because Corynebacterium diphtheriae is the causative agent of diphtheria, a more severe respiratory infection.
**Option B:** Incorrect because Staphylococcus aureus is a common cause of skin infections, but not erythrasma specifically.
**Option C:** Incorrect because Pseudomonas aeruginosa can cause a variety of infections, including skin and soft tissue infections, but it is not the primary cause of erythrasma.
**Clinical Pearl / High-Yield Fact**
Remember that erythrasma is a superficial infection that can be distinguished from deeper infections by its well-demarcated borders and characteristic coloration.
**Correct Answer:** D. Corynebacterium minutissimum.