Differential Diagnosis for Peutz-Jeghers Syndrome

Given the presentation of a 23-year-old woman with darkened lips and no significant history, the differential diagnosis can be organized into the following categories:

• Single Most Likely Diagnosis

  • Peutz-Jeghers Syndrome: This condition is characterized by the presence of hamartomatous polyps in the gastrointestinal tract and mucocutaneous melanin deposits, which could explain the darkened lips. The syndrome also carries an increased risk of various cancers, making it a critical diagnosis to consider.

• Other Likely Diagnoses

  • Addison's Disease: This endocrine disorder can cause hyperpigmentation, including darkening of the lips, due to increased levels of adrenocorticotropic hormone (ACTH), which stimulates melanin production.
  • McCune-Albright Syndrome: Although more commonly associated with café-au-lait spots, this syndrome can also present with mucocutaneous pigmentation changes and is known for its association with various endocrine and bone disorders.
  • Carney Complex: This rare genetic disorder can present with mucocutaneous melanin deposits similar to Peutz-Jeghers Syndrome, along with other features like myxomas and endocrine disorders.

• Do Not Miss Diagnoses

  • Malignant Melanoma: Although less likely given the patient's age and presentation, any new or changing pigmentation should prompt consideration of melanoma, especially if there are other suspicious skin lesions.
  • Neurofibromatosis Type 1 (NF1): While NF1 is more commonly associated with café-au-lait spots, it can also present with other skin manifestations, and the diagnosis is critical due to its implications for tumor risk and other systemic involvement.

• Rare Diagnoses

  • LEOPARD Syndrome: A rare genetic disorder characterized by lentigines (multiple), electrocardiographic conduction abnormalities, ocular hypertelorism, pulmonary stenosis, abnormal genitals, retardation of growth, and sensorineural deafness. Mucocutaneous pigmentation changes could be a presenting feature.
  • Carney-Stratakis Syndrome: A rare condition characterized by paragangliomas, gastrointestinal stromal tumors (GISTs), and mucocutaneous pigmentation, which could be considered in the differential for Peutz-Jeghers Syndrome due to overlapping features.