Table of Contents
Definition / general | Epidemiology | Clinical features | Clinical images | Microscopic (histologic) description | Additional referencesCite this page: Hamodat M. Miliaria. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skinnontumormiliaria.html. Accessed November 27th, 2024.
Definition / general
- Obstruction of sweat gland ducts during high heat and humidity
Epidemiology
- Most often seen in children but may affect any age
Clinical features
- Miliaria crystallina: obstruction is within stratum corneum, resulting in small clear vesicles located on trunk with high fever and pronounced sweating
- Miliaria profunda: seen in tropical climates, obstruction is at sweat duct, resulting in small papules on trunk and occasionally on extremities
- Miliaria pustulosa: miliaria rubra with pustules
- Miliaria rubra (prickly heat): obstruction within prickle cell layer, resulting in extremely pruritic erythematosus papules and vesicles usually located about the trunk and intertrigenous regions; common in infants
Microscopic (histologic) description
- Miliaria crystallina: subcorneal vesicle with few neutrophils; obstruction is within stratum corneu
- Miliaria rubra: intraepidermal spongiotic vesicle
- In both variants, lesion is centered around an intraepidermal eccrine sweat duct
- Miliaria profunda: spongiosis of dermal portion of eccrine sweat duct; often with adjacent chronic inflammation
- Miliaria pustulosa: features of miliaria plus intraepidermal or subcorneal pustules