HACEK group of organisms includes all except:
**Core Concept**
The HACEK group of organisms is a collection of bacteria that are typically fastidious and difficult to culture. These bacteria are commonly found in the human oral cavity and are known to cause endocarditis, particularly in individuals with pre-existing heart conditions.
**Why the Correct Answer is Right**
The HACEK group includes Haemophilus species (such as Haemophilus parainfluenzae), Aggregatibacter species (such as Aggregatibacter actinomycetemcomitans), Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae. These bacteria require special culture media to grow, as they are fastidious and have specific nutritional requirements. They are usually transmitted through the oral route and can cause infections such as endocarditis, particularly in individuals with pre-existing heart conditions.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as it is not a member of the HACEK group.
* **Option B:** This option is incorrect as it is not a member of the HACEK group.
* **Option C:** This option is incorrect as it is not a member of the HACEK group.
**Clinical Pearl / High-Yield Fact**
The HACEK group of organisms is often difficult to culture and requires special culture media. A high index of suspicion is necessary to diagnose infections caused by these organisms, particularly in individuals with pre-existing heart conditions.
**Correct Answer: D.**