Differential Diagnosis for Small Cluster Vesicles under Nose in Woman with Behcet's

• Single most likely diagnosis
  • Behcet's disease oral ulcers: Given the patient's history of Behcet's disease, the most likely diagnosis is oral ulcers associated with the condition. Behcet's disease is a form of vasculitis that can cause a wide range of symptoms, including oral ulcers, genital ulcers, and skin lesions.
• Other Likely diagnoses
  • Herpes simplex virus (HSV) infection: HSV can cause small cluster vesicles, especially in the oral and perioral area. The patient's immune system may be compromised due to Behcet's disease, making her more susceptible to HSV infections.
  • Aphthous ulcers: These are common, recurrent ulcers that can appear in the oral cavity, including under the nose. They may be triggered by stress, trauma, or certain foods.
  • Contact dermatitis: Irritation from contact with certain substances, such as fragrances or metals, can cause vesicular eruptions in the affected area.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Erythema multiforme: This is a severe skin condition that can be triggered by infections, medications, or other factors. It can cause vesicles and ulcers, and can be life-threatening if not treated promptly.
  • Stevens-Johnson syndrome: This is a rare but life-threatening condition that can cause severe skin and mucous membrane lesions, including vesicles and ulcers.
• Rare diagnoses
  • Pemphigus vulgaris: This is a rare autoimmune disease that can cause blistering lesions in the skin and mucous membranes, including the oral cavity.
  • Bullous pemphigoid: This is another rare autoimmune disease that can cause blistering lesions, often in older adults.
  • Epidermolysis bullosa acquisita: This is a rare autoimmune disease that can cause blistering lesions, often in response to trauma or other triggers.