Stool examination is required for diagnosis of infection with –
**Core Concept**
The stool examination is a crucial diagnostic tool for detecting infections caused by certain pathogens that reside in the gastrointestinal tract. This examination helps in identifying the causative agent, which is essential for initiating appropriate treatment and preventing further transmission.
**Why the Correct Answer is Right**
The correct answer involves identifying the pathogen that is typically diagnosed through stool examination. This involves understanding the lifecycle and transmission of the pathogen, as well as the clinical presentation of the disease. For example, pathogens like *Giardia lamblia*, *Entamoeba histolytica*, and *Cryptosporidium* species are commonly diagnosed through stool examination due to their presence in the gastrointestinal tract.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as the pathogen typically diagnosed through blood examination or serological tests, not stool examination.
* **Option B:** This option is incorrect as the pathogen is usually diagnosed through respiratory or skin examination, not stool examination.
* **Option C:** This option is incorrect as the pathogen is typically diagnosed through urine or blood examination, not stool examination.
**Clinical Pearl / High-Yield Fact**
A high-yield fact to remember is that stool examination is essential for diagnosing infections caused by *Giardia lamblia*, *Entamoeba histolytica*, and *Cryptosporidium* species, which are common causes of gastroenteritis worldwide.
**Correct Answer: D.**