Differential Diagnosis for Red Mark on Hard Palate

• Single most likely diagnosis
  • Trauma (e.g., from a sharp object or hot food): This is the most likely diagnosis due to the common occurrence of accidental injuries to the hard palate.
• Other Likely diagnoses
  • Aphthous ulcer: These are common oral ulcers that can appear on the hard palate, often caused by stress, minor mouth injury, or certain foods.
  • Erosive lichen planus: An autoimmune condition that can cause red, inflamed areas on the mucous membranes inside the mouth, including the hard palate.
  • Nicotinic stomatitis: Associated with smoking, this condition can cause red, inflamed areas on the hard palate.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Oral cancer: Although less common, any unusual or persistent red mark on the hard palate should be evaluated for the possibility of oral cancer, especially in individuals with risk factors such as smoking or tobacco use.
  • Infectious diseases (e.g., syphilis, tuberculosis): Certain infectious diseases can cause oral lesions, including on the hard palate, and are critical to diagnose due to their potential severity and need for specific treatment.
• Rare diagnoses
  • Erythroplakia: A rare condition characterized by a red patch or plaque on the mucous membrane that cannot be rubbed off and is often associated with an increased risk of cancer.
  • Pemphigus: A group of rare skin disorders that cause blistering of the skin and mucous membranes, including the hard palate.
  • Kaposi's sarcoma: A type of cancer that can cause lesions on the hard palate, more commonly seen in immunocompromised individuals, such as those with HIV/AIDS.