Atrophoderma of Pasini and Pierini - APP
Atrophoderma of Pasini and Pierini (APP) is a benign, slowly progressive form of dermal atrophy of unknown cause. Its defining feature is a marked reduction in the thickness of the dermis, the result of collagen bundles that swell, degenerate, and become abnormally compacted, together with partial thinning or loss of the elastic fiber network.
What sets APP apart from other fibrosing conditions such as scleroderma is that it does not cause the skin to harden (sclero-induration) and it leaves the surface epidermis intact. The thinning happens silently in the deeper dermis: the connective tissue simply becomes thinner without any preceding phase of obvious inflammation or swelling.
APP usually begins in young people (often in adolescence or before age 30) and is more common in women. Lesions tend to appear on the back, chest, and abdomen, and occasionally on the limbs, forming sharply depressed patches that can significantly affect appearance and self-esteem.
At Haute-Derma, we use a thorough, technology-supported diagnostic process to distinguish APP from late-stage localized scleroderma (morphea). We then build a multi-layered treatment plan aimed at halting further tissue loss and restoring a smooth, natural skin surface.
Characteristic Signs and Appearance
In our clinical practice at Haute-Derma, APP is recognized by a set of classic shape and color features:
- "Footprint in the snow" (cliff-drop border): The patches are large, from a few centimeters to tens of centimeters, round or with scalloped edges, and sit 1–2 mm below the surrounding normal skin. The border between normal and affected skin drops off steeply and sharply, so a finger sliding across it feels a sudden step, much like a footprint pressed into a flat layer of snow.
- Secondary color changes: The atrophic skin is usually darker, turning gray-brown, slate-gray, or dusky violet (hyperpigmented patches). In a few cases it stays skin-colored or becomes slightly lighter, giving a mottled appearance.
- Soft skin texture: When pinched or pressed, the affected skin feels completely soft and can be easily lifted and moved. It is not rough, hard, or stuck to the muscle underneath. Hairs and sweat glands in the patch continue to function normally.
How We Diagnose Atrophoderma of Pasini and Pierini at Haute-Derma
Because APP can look very much like late, atrophic-stage localized scleroderma (morphea), Haute-Derma follows a careful differential diagnosis process:
- Dermoscopic assessment of the microcirculation: In APP the small-vessel network looks entirely normal, without the vessel loss or ivory-white fibrotic streaks (fibrotic white tracks) seen in morphea.
- Comparative biopsy at the lesion edge: This is the key to confirming the diagnosis. The doctor takes two punch biopsies for side-by-side comparison: one from the atrophic skin and one from the normal skin right next to it.
- Microscopic structure (H&E): The epidermis is completely normal. In the affected sample, the dermis is 20–50% thinner than in the normal sample. Collagen bundles in the mid and deep dermis are compacted and lie abnormally parallel, sometimes with mild fatty degeneration near the dermal–epidermal junction.
- Elastic fiber stain (Verhoeff–Van Gieson): The elastic network is still present but may be thinner, finer, or more loosely scattered. There is no infiltrate of inflammatory cells (lymphocytes, plasma cells) around the blood vessels or skin appendages.
Specialist Treatment at Haute-Derma
Although APP is considered self-limiting (it usually stops progressing after several years of quiet activity), the deep depressions and darker color it leaves behind are permanent without specialist medical treatment. Our protocol at Haute-Derma has two goals:
- Medical Treatment to Halt the Active Phase
- Extended systemic antibiotic therapy: Some studies suggest an epidemiologic link between APP and infection with Borrelia burgdorferi (the cause of Lyme disease). When lesions are still spreading and serology is positive, the doctor may prescribe a dedicated course of oral antibiotics (such as doxycycline) to slow the atrophic process.
- Topical immunomodulators: Calcineurin inhibitor creams or high-strength retinoids are applied to the edges of the lesion to stabilize fibroblast activity and stop the patch from enlarging.
- Advanced Therapies to Rebuild Dermal Volume: To fill in the steep-edged depressions and even out the gray-brown discoloration, Haute-Derma combines the latest technologies.
- Fractional CO2 / Er:YAG laser: Thermal energy creates tiny, sterile micro-injuries that reach down into the compacted dermis. This breaks up old, degenerated collagen and prompts fibroblasts to restart production, laying down fresh collagen that gradually lifts the floor of the depression back toward the level of the surrounding skin.
- Autologous growth factor therapy with biological mesotherapy: High-concentration platelet-rich plasma (PRP), combined with growth-stimulating amino acids, is micro-injected directly into the depressed area. Growth factors such as PDGF and TGF-β stimulate new blood vessels to nourish the atrophic tissue and help reverse thinning of the deep dermis.
- Q-switched Nd:YAG / PicoSure laser (1064 nm): Treats the darker pigmentation of the patches. Ultra-short laser pulses shatter melanin deposits in the dermis into tiny particles that macrophages then clear away, helping to even out the color between affected and normal skin.
