Miliaria crystallina in Infant/Neonate
Miliaria crystallina, also referred to as sudamina, is due to occlusion of the eccrine ducts at the superficial epidermis or stratum corneum. It may occur at any age but is common in neonates and infants, probably secondary to the immaturity and weakness of the duct structure. Clinically, it presents as largely asymptomatic 1- to 2-mm fragile vesicles. It has predilection for the face, neck, upper torso, and occluded areas. Fever, exposure to warm and humid environmental conditions, and occlusion (excessive clothing or swaddling) are predisposing factors.
Superficial occlusion is thought to result from increased hydration compounded with humidity and sweating. When the occlusion of the sweat duct is deeper in the epidermis, miliaria rubra (prickly heat), miliaria pustulosa, or miliaria profunda (skin-colored papules with possible associated hypohidrosis or anhidrosis) may result.
L74.1 – Miliaria crystallina
44279002 – Miliaria crystallina
Differential Diagnosis & Pitfalls
- Miliaria rubra and miliaria profunda – These miliaria variants are not vesicular and present as papules and/or pustules.
- Neonatal varicella / varicella – Presents with vesicles on an erythematous base (eg, "dewdrops on a rose petal") and with lesions in different stages.
- Incontinentia pigmenti – Stage 1 (vesicular); swirled and linear Blaschkoid pattern.
- Scabies – Vesicles and burrows. Examine caregivers.
- Impetigo – More bulbous but also fragile, leading to erosions.
- Folliculitis – Has follicular-based pustules.
- Neonatal herpes simplex virus (HSV) infection / HSV infection – Presents with painful crops of vesicles that often occur near a mucosal surface.
- Acute generalized exanthematous pustulosis (AGEP) – Pustules are opaque, not clear as in miliaria.
- Lesions may resemble toxic epidermal necrolysis with the presence of desquamation. However, miliaria crystallina does not have the intense erythema, mucosal involvement, or systemic illness associated with toxic epidermal necrolysis.
- Vesicular drug eruption
Drug Reaction Data