The Oldest New Finding in Atopic Dermatitis

Abstract

In 1947, Sulzberger and colleagues published a micrograph of a blocked acrosyringium in a patient with atopic dermatitis (AD), believing that it had a large role in the disease process. Lacking appropriate probes, they could not confirm the finding.Objective: To confirm the observations by Sulzberger et al on the blockage of sweat ducts in AD in pathologic specimens.Design and Setting: Biopsy specimens diagnostic of various inflammatory diseases and with a secondary differential diagnosis of eczema were evaluated at an academic medical center.Exposures: Evidence of ductal obstruction in each specimen was examined following staining with hematoxylin-eosin, periodic acid-Schiff, and Gram stain.Main Outcomes and Measures: Comparison of biopsy specimens with control specimens and additional controls consisting of noninflamed skin.Results: Using 36 biopsy specimens, this study confirmed the observations by Sulzberger et al on the blockage of sweat ducts in AD. Blocked acrosyringia were noted in each specimen on routine staining with hematoxylineosin. The study also confirmed the findings by earlier investigators about the blockage of sweat ducts in miliaria, showing eosinophilic material in the ducts that was positive for periodic acid-Schiff. Previous researchers also observed bacteria in the blockages, and this study demonstrated the same findings in AD, rather than miliaria. Conclusion and Relevance:Subclinical miliaria may be the earliest change in AD and likely initiates the process that causes intense pruritus.

The Presence and Impact of Biofilm-Producing Staphylococci in Atopic Dermatitis

“…They also support the concept that subclinical miliaria is an important feature of AD, whereby the biofilms occlude the sweat ducts. 3 Our finding that S aureus is more prevalent in lesions is in accordance with previously presented work. 12 Our pathologic findings show occluded eccrine ducts; we reported previously that this is the first time, to our knowledge, this has been noted since Sulzberger's observation in 1947.…”

“…12 Our pathologic findings show occluded eccrine ducts; we reported previously that this is the first time, to our knowledge, this has been noted since Sulzberger's observation in 1947. 3,28 Occluded sweat ducts ordinarily mean miliaria, 29 but with the addition of an accompanying genetic defect, we believe that AD also must be considered. We have demonstrated that the pathogenesis of these 2 diseases is similar; the PAS-positive ductal obstruction (representing biofilms) is the common link.…”

Impact of climate change on atopic dermatitis: A review by the International Eczema Council

“…Global warming leads to increased temperature that can induce the production of proinflammatory cytokines and pruritus and aggravate AD 20 . Additionally, it has been hypothesized that subclinical miliaria due to increased temperature and sweating can precipitate pruritus and development of AD 21 . Warming also causes alteration in the production, distribution, and dispersion of aeroallergens, allergen proteins, and air pollutants.…”

Why does sweat lead to the development of itch in atopic dermatitis?

“…Consequently, sweat retention caused by keratin plugs caused both inflammation around the sweat gland apparatus and itch. Occlusion of sweat pores by periodic acid‐Schiff stain (PAS)‐positive substances, biofilms derived from Staphylococcus epidermidis , may be involved in the pathogenesis of miliaria . Formation of similar keratin plugs in AD has also been confirmed, as described below …”