Measles (Rubeola) Rash
Measles is characterized by a classic maculopapular rash that follows a specific progression, often preceded by prodromal symptoms (fever, cough, coryza, and conjunctivitis).
1. Rash Characteristics
- Progression: Begins on the face/hairline and spreads downward (cephalocaudal) to the trunk and extremities.
- Features: Initially, discrete maculopapules that become confluent.
- Timing: Appears 3–5 days after the onset of prodromal symptoms.
2. Differential Diagnosis (Exanthems)
| Condition | Key Differentiating Feature |
|---|---|
| Rubella | Milder symptoms: postauricular/occipital lymphadenopathy (Forchheimer spots). |
| Roseola | Rash appears after the fever resolves. |
| Scarlet Fever | “Sandpaper” texture; circumoral pallor; strawberry tongue. |
| Erythema Infectiosum | “Slapped cheek” appearance; reticular rash. |
NEET PG Hint: Never forget Koplik spots, which are pathognomonic for measles; they appear on the buccal mucosa 1–2 days before the rash. Also, remember that measles is highly contagious, and the most common cause of death among these rashes is secondary pneumonia.