An 18-year-old woman was diagnosed 7 years earlier with precocious pseudopuberty secondary to ovarian tumor. Physical examination reveals oral and lingual dark pigmentation. Which of the following is the most likely diagnosis?
An 18-year-old woman was diagnosed 7 years earlier with precocious pseudopuberty secondary to ovarian tumor. Physical examination reveals oral and lingual dark pigmentation. Which of the following is the most likely diagnosis?
💡 Explanation
## **Core Concept**
The question describes a case of precocious pseudopuberty due to an ovarian tumor, accompanied by oral and lingual dark pigmentation. This combination of symptoms suggests a condition that involves hormonal overproduction, likely androgens or estrogen, and possibly melanin-stimulating factors.
## **Why the Correct Answer is Right**
The correct answer, **McCune-Albright Syndrome**, is a genetic disorder characterized by the classic triad of:
- **Precocious puberty** (often presenting as pseudopuberty in females due to estrogen-producing ovarian tumors),
- **Polyostotic fibrous dysplasia** (not mentioned but a key component),
- **Cafe-au-lait spots** or oral and lingual melanin deposits leading to **dark pigmentation**.
The syndrome results from mutations in the GNAS gene, leading to constitutive activation of Gsα protein, which in turn causes overproduction of cAMP. This results in the excessive production of hormones, including sex steroids (like estrogen from ovarian tumors) and melanocyte-stimulating hormone (MSH), leading to pigmentation changes.
## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is not provided, but based on the context, any condition not matching the described syndrome would be incorrect.
- **Option B:** Without specifics, we assume any other option does not align with the constellation of symptoms described for McCune-Albright Syndrome.
- **Option C:** Similarly, without details, we infer it doesn't fit the clinical picture provided.
- **Option D:** This would also not match the clinical presentation of McCune-Albright Syndrome.
## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that McCune-Albright Syndrome is associated with ** café-au-lait spots**, which are a form of post-inflammatory hyperpigmentation. These spots and the oral/lingual dark pigmentation mentioned are crucial diagnostic clues. Additionally, the syndrome's association with **precocious puberty** and **fibrous dysplasia** makes it a multisystem disorder that requires comprehensive management.