Miliaria

Key Points
Skin condition also known as Sweat rash, typically affecting skin folds and areas exposed to friction, which takes several differing forms
Caused by blockage of sweat ducts
Symptoms predicated on the specific form of the condition

Miliaria, or Sweat rash, is a skin condition which typically affects skin folds and other areas of the body exposed to friction. The condition generally appears on the neck, groin, or armpits, but may appear in other areas, including the face. It takes several differing forms, which have disparate symptoms.

Miliaria crystallina occurs when blockage of the sweat ducts is close to the surface, and consists of small blisters which are clear and may be easily broken open. Miliaria rubra, also known as prickly heat, results from blockages deeper in the upper layer of skin, and consists of red papules accompanied by intense itching. Miliaria profunda sees blockages which case sweat to leak into the dermis (lower skin layer), and presents as red lumps which cause severe discomfort. Miliaria pustulosa refers to existing pustules affected by inflammation and secondary bacterial infection.

Miliaria is caused by the blockage of sweat ducts. The condition is most common in humid, hot climates, but may also be seen in desert climates, affecting approximately 1/3 of persons exposed to these conditions. Excessive sweating and synthetic clothing may exacerbate the condition. Infants are also prone to its development. The condition will typically last up to six weeks, even with treatment.

Differential Diagnosis (Other conditions with similar appearance)
Candidiasis, Cutaneous
Pityrosporum Folliculitis
Chickenpox
Pseudomonas Folliculitis
Erythema Toxicum Neonatorum
Folliculitis
Herpes simplex

Diagnosis
Key Points
Diagnosis based on appearance of the affected area
Other testing is not generally required

Miliaria is typically diagnosed based on the characteristic appearance of the affected area. Other testing is not generally required.

Treatment
Avoiding sweating is key to preventing further exacerbation of the condition
Goal of treatment is the manage symptoms and encourage healing
In severe cases, Topical steroids may be prescribed
OTC Options: calamine lotion, antiseptics and antibacterial cleansers

Treatment of miliaria typically consists of symptom management and the encouragement of healing. However, even with treatment, the condition may take up to 6 weeks to resolve, as blockages are removed as part of the normal skin growth process. However, there are several measures affected persons may take to relieve symptoms and manage the condition. Avoiding sweating and irritation, use of cool compresses, and calamine lotion may prevent further exacerbation and relieve discomfort. Antiseptic and antibacterial cleansers may assist in preventing secondary infection. In severe cases, topical steroids may be prescribed to relieve symptoms.