A young 8-year old boy presents with multiple discrete, shiny, pin-head papules on dorsal aspect of hand, forearms and shaft of penis. The diagnosis is:
**Core Concept**
The condition described is a classic presentation of a sexually transmitted infection (STI) that affects children, caused by a bacterium that is usually transmitted through skin-to-skin contact.
**Why the Correct Answer is Right**
The condition is caused by *Klebsiella granulomatis* (formerly known as Calymmatobacterium granulomatis), a gram-negative bacterium. The bacteria infect the skin, leading to the formation of multiple discrete, shiny, pin-head papules on the affected areas. The infection is often associated with lymphadenopathy (swollen lymph nodes) and can be transmitted through skin-to-skin contact, including sexual contact, or through contaminated water. The condition is more common in tropical regions and is often seen in children who have been exposed to contaminated water.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the condition described is not caused by a viral infection such as warts, which are typically caused by the human papillomavirus (HPV).
**Option B:** This option is incorrect because scabies is caused by the mite Sarcoptes scabiei and typically presents with intense itching, burrows, and a rash, not discrete papules.
**Option C:** This option is incorrect because impetigo is a bacterial infection caused by Staphylococcus aureus or Streptococcus pyogenes, which typically presents with honey-colored crusts and a red base, not discrete papules.
**Clinical Pearl / High-Yield Fact**
This condition is often associated with a history of exposure to contaminated water, such as swimming in lakes or rivers, and is more common in tropical regions. It's essential to consider this condition in children who present with multiple discrete papules on the skin.
**Correct Answer: D. Donovanosis**