Differential Diagnosis for Increased Pigmentation in the Face

• Single Most Likely Diagnosis
  • Melasma: This is the most common cause of increased pigmentation in the face, particularly in women. It is characterized by patches of discoloration, usually on the cheeks and forehead, and is often associated with hormonal changes, sun exposure, and genetic predisposition.
• Other Likely Diagnoses
  • Post-Inflammatory Hyperpigmentation (PIH): This condition occurs after inflammation or injury to the skin, leading to increased melanin production and resulting in darker skin areas. It's common in acne, eczema, or after cosmetic procedures.
  • Solar Lentigines (Sun Spots): These are flat brown or black spots that appear due to sun exposure. They are more common in older adults and in individuals who spend a lot of time outdoors without adequate sun protection.
• Do Not Miss Diagnoses
  • Addison's Disease: Although rare, this condition, characterized by adrenal insufficiency, can cause hyperpigmentation, particularly in areas exposed to the sun, as well as in palmar creases, scars, and mucous membranes. Missing this diagnosis could be life-threatening due to the potential for acute adrenal crisis.
  • Malignant Melanoma: While less common than other forms of skin cancer, melanoma can present as a new or changing pigmented lesion. Early detection is crucial for survival, making it a "do not miss" diagnosis.
• Rare Diagnoses
  • Erythromelanosis Follicularis Faciei: A rare condition characterized by reddish-brown pigmentation on the face, typically affecting the preauricular area. It's more common in males and can be associated with other skin and hair abnormalities.
  • Poikiloderma of Civatte: This condition presents with a mixture of atrophy, telangiectasia, and pigmentation changes, typically on the sides of the neck. It's thought to be related to sun exposure and is more common in fair-skinned individuals.