The granules discharged in mycetoma contains
**Core Concept**
Mycetoma is a chronic, granulomatous infection of the skin and subcutaneous tissue caused by filamentous bacteria (Actinomadura, Nocardia, Streptomyces) or fungi (Madurella, Fusarium). The disease is characterized by the formation of granules, which are composed of the infecting organism, dead tissue, and inflammatory cells.
**Why the Correct Answer is Right**
The granules in mycetoma are formed as a result of the body's attempt to wall off the infecting organism. The granules are composed of a mixture of the causative organism, necrotic tissue, and inflammatory cells, including macrophages and giant cells. The granules are typically discharged from the skin surface as a result of the body's attempt to eliminate the infection. This process is facilitated by the presence of enzymes such as keratinase, which breaks down keratin and helps to liquefy the granules.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not describe the composition of the granules in mycetoma.
**Option B:** This option is incorrect because it is a characteristic of other types of infections, not mycetoma.
**Option C:** This option is incorrect because it is a type of bacterial cell wall component, not a component of mycetoma granules.
**Clinical Pearl / High-Yield Fact**
Mycetoma should be differentiated from other conditions that present with granulomatous lesions, such as sarcoidosis or granuloma annulare. The presence of granules in a chronic skin infection should raise suspicion for mycetoma.
**Correct Answer: D. Dead tissue, inflammatory cells, and the causative organism.**