In plain words
Miliaria is also called heat rash. It looks like tiny clear or red bumps, often on the neck, chest, back, or in skin folds. Sweat gets trapped under the skin when the tiny ducts block. It happens when a baby is too warm, often from too many layers, heavy blankets, or a hot room. It usually fades as the baby cools down. A rash that spreads, looks infected, or comes with a fever needs a call to your pediatrician. A fever in a young baby is an emergency, so call right away.
The deeper version
Miliaria is an eruption caused by obstruction of eccrine sweat ducts. Miliaria crystallina (superficial clear vesicles) and miliaria rubra (red papules from deeper retention) are the common forms. They are more frequent in neonates because sweat glands are immature and thermoregulation is limited. Occlusion, heat, and humidity are the main triggers, which is why over-wrapping is a recognized risk. Diagnosis is clinical, but it should not be assumed when a rash has fever, pustules, or spreads, because neonatal infections can mimic it. Eichenfield and colleagues' neonatal dermatology text (Neonatal and Infant Dermatology, 3rd edition, 2015) covers the differential. The main controversy in practice is how much clothing and bedding a baby needs, and when a rash should be tested.
Where it comes up
- Baby acne, cradle cap, and rashesBaby Basics
- Bathing a newbornBaby Basics
- Swaddling: how and when to stopBaby Basics
- Newborn sleep and safe sleepBaby Basics
What mothers here say about miliaria
No one has posted under this term yet.
Sources
- Eichenfield LF and colleagues — Neonatal and Infant Dermatology, 3rd edition (2015)