Differential Diagnosis for Skin Lesions

The description provided suggests a condition that involves the appearance of skin lesions with specific characteristics, including becoming red, itchy, burning, and then resolving with scarring and a central tiny hole. Here's a differential diagnosis organized into the requested categories:

• Single Most Likely Diagnosis
  • Folliculitis: This condition involves inflammation of the hair follicles, which can cause redness, itching, and burning sensations. It often resolves on its own but can leave scarring and, in some cases, a small pit or hole if the follicle is severely damaged.
• Other Likely Diagnoses
  • Furuncle (Boil): A furuncle is an infection of the hair follicle that can extend into the deeper tissue, causing more severe symptoms like increased redness, swelling, and pain. It can resolve with scarring and sometimes leaves a small hole or pit.
  • Kerion: A severe form of tinea capitis (ringworm of the scalp), kerion can cause inflamed, painful lesions that may lead to scarring and hair loss. The lesions can have a central area of clearing or a small hole.
  • Pyoderma Gangrenosum: Although less common, this condition starts as a small pustule or blister that progresses to a painful nodule or ulcer, which can have a characteristic "punched-out" appearance with a central hole. It often heals with scarring.
• Do Not Miss Diagnoses
  • Squamous Cell Carcinoma: While less likely, any new or changing skin lesion, especially those that ulcerate or have a central hole, should prompt consideration of skin cancer. Squamous cell carcinoma can present in various ways, including as a firm, growing nodule or ulcer.
  • Methicillin-Resistant Staphylococcus aureus (MRSA) Infection: MRSA infections can cause skin lesions that are red, swollen, and painful, and can lead to serious complications if not treated properly. They may resemble boils or abscesses and can leave scarring.
• Rare Diagnoses
  • Ecthyma Gangrenosum: A rare but serious condition associated with Pseudomonas aeruginosa infection, typically in immunocompromised patients. It presents as a skin lesion that progresses to a gangrenous ulcer with a black eschar and can have a central hole.
  • Cutaneous Leishmaniasis: Caused by Leishmania parasites, this condition can result in skin lesions that ulcerate and may leave scars with a central hole or depression upon healing.

Each of these diagnoses has a brief justification based on the symptoms described. The key to narrowing down the differential diagnosis is a thorough clinical evaluation, including the patient's medical history, physical examination, and potentially, diagnostic tests such as cultures, biopsies, or imaging studies.