Miliaria are caused by obstruction of the sweat glands. There are three stages of Miliaria called Miliaria sudamina, Miliaria rubra, and Miliaria profunda (listed from mildest and most superficial to the most severe and deep forms). The condition occurs in those exposed to heat for prolonged periods of time, in infants, and in the obese. This picture is a close-up of the most severe form. Note the numerous papules on the surface of the skin.
Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.