[2] The usual presentation of Kyrle disease consists of nodules and hyperkeratotic papules with a central keratotic plug.

[3] Papules in perforating folliculitis are usually localized to areas of the extremities (arms, thighs, and buttocks) that bear hair.

Numerous explanations, such as infection, aberrant keratinization, impaired differentiation of the epidermis and dermo-epidermal junction, increased fibronectin concentrations in tissue and serum, uremia (renal failure), and hyperphosphatemia (diabetes mellitus), have been put forth in the literature.

The more common relationship with chronic renal failure suggests a pathogenetic link, even though some associations may just be coincidental.

[4] The patient's medical history, the lesions' clinical appearance, and—most importantly—histopathology with the identification of typical histological characteristics are all important in the diagnosis of acquired perforating dermatosis.