Differential Diagnosis for Ambiguous Genitalia
- Single Most Likely Diagnosis
- Congenital Adrenal Hyperplasia (CAH): This is the most common cause of ambiguous genitalia in newborns, resulting from a deficiency in enzymes involved in cortisol production, leading to an overproduction of androgens.
- Other Likely Diagnoses
- Androgen Insensitivity Syndrome (AIS): A condition where an individual has a Y chromosome but is resistant to androgens, resulting in the development of female external genitalia despite the presence of testes.
- Mixed Gonadal Dysgenesis: A condition characterized by the presence of both ovarian and testicular tissue, often resulting in ambiguous genitalia.
- Ovotesticular Disorder of Sex Development (OT-DSD): A condition where an individual has both ovarian and testicular tissue, which can lead to the development of ambiguous genitalia.
- Do Not Miss Diagnoses
- Congenital Adrenal Hyperplasia (CAH) due to 21-Hydroxylase Deficiency (already mentioned, but included here due to its potential severity if missed): If not promptly diagnosed and treated, CAH can lead to life-threatening complications such as adrenal crisis.
- Salt-Wasting CAH: A severe form of CAH that can lead to dehydration, electrolyte imbalances, and shock if not promptly recognized and treated.
- Rare Diagnoses
- Denys-Drash Syndrome: A rare condition characterized by the presence of ambiguous genitalia, nephropathy, and an increased risk of Wilms tumor.
- Frasier Syndrome: A rare condition characterized by the presence of ambiguous genitalia, nephropathy, and an increased risk of gonadal tumors.
- Leydig Cell Hypoplasia: A rare condition characterized by a deficiency in Leydig cells, leading to inadequate androgen production and the development of ambiguous genitalia.
- Mayer-Rokitansky-Küster-Hauser (MRKH) Syndrome with Androgen Excess: A rare condition characterized by the presence of a Y chromosome, androgen excess, and the development of ambiguous genitalia.