Differential Diagnosis for Raised Bumps Rash
Single Most Likely Diagnosis
- Urticaria (Hives): This is the most likely diagnosis given the sudden onset of raised bumps rash within 15 minutes. Urticaria is characterized by itchy, raised welts that can appear anywhere on the body and are often triggered by allergic reactions, infections, or autoimmunity.
Other Likely Diagnoses
- Insect Bites or Stings: These can cause rapid onset of raised bumps due to an allergic reaction to the venom. The reaction can range from mild to severe.
- Contact Dermatitis: This is a type of skin inflammation caused by contact with irritants or allergens, leading to a rash that can include raised bumps. The onset can be rapid if the substance is highly irritating or if the individual has a strong allergic response.
- Allergic Reaction to Medication: Certain medications can cause allergic reactions that manifest as a rash with raised bumps. The timing of the reaction can vary but often occurs within minutes to hours after exposure.
Do Not Miss Diagnoses
- Anaphylaxis: Although anaphylaxis is a severe, whole-body allergic reaction that can include symptoms like difficulty breathing, rapid heartbeat, and a fall in blood pressure, it can initially present with skin manifestations such as a rash with raised bumps. It's critical to identify and treat anaphylaxis promptly as it can be life-threatening.
- Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN): These are severe skin and mucous membrane disorders, usually a reaction to medication or infection. Early stages might resemble a rash with raised bumps, but they can rapidly progress to blistering and peeling of the skin, which can be fatal if not recognized and treated early.
Rare Diagnoses
- Mastocytosis: A condition characterized by an accumulation of mast cells in one or more organs, which can lead to a variety of symptoms including skin lesions that might resemble raised bumps. The onset can be sudden in some cases.
- Erythema Multiforme: An immune-mediated disorder that can cause target-like lesions on the skin, which might initially appear as raised bumps. It's often triggered by infections or medications.