Atrophoderma of Pasini and Pierini (APP) is an uncommon skin condition characterized by indented, asymptomatic patches with a distinctive ‘cliff-drop’ border. Understanding the differential diagnosis of Atrophoderma of Pasini and Pierini is crucial for accurate diagnosis and patient management. This article provides a comprehensive overview of APP, focusing on its clinical features and differential diagnosis to aid in distinguishing it from similar conditions.
Alt: Clinical presentation of Atrophoderma of Pasini and Pierini showing depressed skin lesions
Who is Affected by Atrophoderma of Pasini and Pierini?
Atrophoderma of Pasini and Pierini is considered a rare dermatological condition, with approximately only 100 cases documented in medical literature. It typically manifests during adolescence or early adulthood, specifically in the second and third decades of life. However, cases have been reported across all age groups, including infancy, childhood, and late adulthood, and even congenital instances.
The condition exhibits a notable gender bias, with a higher prevalence in females compared to males (ratio of 2-6:1). Most reported cases are in individuals of Caucasian descent, although familial occurrences have also been noted, suggesting a potential genetic predisposition in some instances.
Infantile Atrophoderma of Pasini and Pierini
Alt: 10-month-old infant exhibiting early signs of Atrophoderma of Pasini and Pierini
Alt: Progression of Atrophoderma of Pasini and Pierini in a baby at 20 months old
Alt: Close-up view of Atrophoderma of Pasini and Pierini lesion showing visible subcutaneous vessels
Etiology and Pathogenesis of Atrophoderma of Pasini and Pierini
The exact cause of Atrophoderma of Pasini and Pierini remains unclear. It is widely considered to be a variant of morphoea (localized scleroderma) due to overlapping clinical and histopathological characteristics, and its occasional association with typical morphoea lesions in some patients. This suggests a possible position within the scleroderma spectrum of disorders.
Interestingly, a subset of APP patients have demonstrated the presence of antibodies against Borrelia burgdorferi, the bacteria responsible for Lyme disease. In these cases with IgM antibodies, treatment with doxycycline has shown some success in improving the skin lesions, hinting at a possible infectious trigger in certain individuals.
Clinical Manifestations of Atrophoderma of Pasini and Pierini
The hallmark of Atrophoderma of Pasini and Pierini is the appearance of asymptomatic, depressed skin areas. These lesions are commonly found on the trunk, particularly the lower back region.
Key clinical features include:
- Appearance: Depressed, slightly sunken areas of skin.
- Location: Predominantly on the trunk, especially the lower back.
- Number and Size: Can be solitary or multiple lesions, ranging in size from 1–2 cm up to 15 cm in diameter and 1–8 mm in depth. Lesions are typically oval or round in shape.
- Distribution: Lesions may present a ‘footprints-in-the-snow’, Swiss-cheese, or ‘moth-eaten’ pattern due to their multiple and sometimes coalescing nature.
- Inflammation: Absence of preceding inflammatory signs is characteristic.
- Pattern: The distribution can be unilateral, bilateral and symmetrical, linear, zosteriform, or following Blaschko lines.
- Skin Color: Overlying skin color can vary, presenting as hyperpigmented, hypopigmented, or normal in color relative to surrounding skin.
- Texture: The surface skin is not wrinkled, and induration (hardening) is not typically palpable.
- ‘Cliff-drop’ Edge: A sharply defined, abrupt border demarcates the lesion from the surrounding normal skin, best appreciated with angled lighting. This ‘cliff-drop’ edge is a defining characteristic.
Alt: Hyperpigmented lesions characteristic of Atrophoderma of Pasini and Pierini on the back
Alt: Distinct ‘cliff-drop’ edge of an Atrophoderma of Pasini and Pierini lesion, highlighted with angled lighting
Dermoscopic Findings in Atrophoderma of Pasini and Pierini
Dermoscopy, a skin surface microscopy technique, can aid in the diagnosis of APP. Typical dermoscopic features include:
- Prominent Pigment Network: Often described as a wavy pattern, irregularly distributed throughout the lesion.
- Regular Perifollicular White Areas: Consistent white areas surrounding hair follicles.
- Retention of Hairs: Hair follicles within the affected area are typically preserved.
Variations in Clinical Presentation Across Skin Types
While Atrophoderma of Pasini and Pierini lesions are frequently described as hyperpigmented in classic presentations, their appearance can differ in individuals with skin of color. In these populations, lesions are more often hypopigmented (lighter than surrounding skin) or skin-colored, which may pose diagnostic challenges if not considered.
Associated Conditions and Complications
Atrophoderma of Pasini and Pierini can occur in association with other connective tissue diseases, most notably morphoea and systemic sclerosis. In some instances, sclerodermatous changes may develop within pre-existing areas of dermal atrophy. These changes, clinically detectable as induration, may histologically resemble morphoea, further supporting the link between these conditions. The potential association with systemic sclerosis necessitates monitoring for systemic involvement in patients diagnosed with APP.
Diagnostic Approach to Atrophoderma of Pasini and Pierini
Diagnosis of Atrophoderma of Pasini and Pierini is primarily based on clinical history and characteristic physical examination findings, particularly the presence of depressed lesions with a ‘cliff-drop’ edge. Dermal atrophy can be objectively demonstrated using ultrasound imaging of the skin.
In regions where Lyme disease is prevalent, serological testing for Borrelia burgdorferi antibodies is recommended to assess for a potential link and guide treatment decisions.
Skin biopsy is not always necessary for diagnosis, but may be considered in atypical presentations or to rule out other conditions in the differential diagnosis. If a biopsy is performed, it should be a deep wedge biopsy taken across the lesion border, including both affected and unaffected skin, extending down to the subcutaneous tissue. Histopathological findings in APP are often subtle and include:
- Epidermis: Normal epidermis with potential basal layer hyperpigmentation.
- Dermis: Dermal atrophy, the hallmark histological feature.
- Collagen and Elastic Fibers: Generally normal collagen and elastic fibers.
- Inflammatory Infiltrate: Perivascular lymphocytic infiltrate, typically mild.
- Sclerosis: Absent or mild deep dermal sclerosis, helping to differentiate it from classic morphoea in some cases.
Atrophoderma of Pasini and Pierini Differential Diagnosis
The differential diagnosis of Atrophoderma of Pasini and Pierini includes several conditions that present with skin atrophy or pigmentary changes. Key conditions to consider include:
- Morphoea (Localized Scleroderma): While APP is considered by many to be a variant of morphoea, typical morphoea lesions often exhibit induration and sclerosis, which are usually absent in APP in the early stages. However, plaque morphoea, particularly the atrophic variant, can be clinically similar. Histopathology and clinical course are crucial in differentiation.
- Lichen Sclerosus: This condition can also present with atrophic white plaques, but typically involves the genital and perianal areas more frequently and often presents with pruritus (itching), which is not characteristic of APP.
- Idiopathic Atrophoderma of Bazex: This rare condition is characterized by symmetrical, sharply demarcated atrophic patches, primarily on the dorsa of the hands and feet. Distribution and location are key differentiating factors.
- Eosinophilic Fasciitis (Shulman Disease): While primarily characterized by induration and deep tissue involvement, the resolving phase can leave behind areas of skin atrophy. However, the preceding inflammatory phase and systemic symptoms help distinguish it from APP.
- Post-inflammatory Hyperpigmentation/Hypopigmentation: These pigmentary changes follow an inflammatory skin condition and lack the characteristic dermal atrophy and ‘cliff-drop’ edge of APP. History of prior inflammation is a key differentiator.
- Linear Atrophoderma of Moulin: Presents as linear band-like depressions, often on the trunk or limbs. While linear, it typically lacks the distinct ‘cliff-drop’ border and is less sharply demarcated than APP.
- Anetoderma: Characterized by focal areas of dermal atrophy with herniation of subcutaneous fat, resulting in lax, wrinkled skin. Anetoderma lesions are typically more raised and lax compared to the depressed lesions of APP.
- Striae Distensae (Stretch Marks): While striae represent dermal atrophy, they are usually linear, associated with rapid skin stretching (e.g., pregnancy, growth spurts), and lack the distinct ‘cliff-drop’ edge of APP. History and morphology are differentiating factors.
Careful clinical examination, considering lesion morphology, distribution, and associated features, alongside histopathology when needed, is essential to accurately differentiate Atrophoderma of Pasini and Pierini from these and other similar conditions.
Management and Treatment Options for Atrophoderma of Pasini and Pierini
Currently, there is no universally recognized or curative treatment for Atrophoderma of Pasini and Pierini. Management primarily focuses on symptomatic relief and addressing any associated conditions.
For cases where Borrelia burgdorferi antibodies are detected, doxycycline treatment may be considered, and has shown improvement in skin lesions in some patients.
In rare instances where APP is associated with other conditions like lupus erythematosus or psoriasis, medications such as hydroxychloroquine and methotrexate, used for these underlying conditions, have been reported to have coincidentally improved APP lesions. However, this is not a standard treatment for APP itself.
Q-switched alexandrite laser (755nm) treatment has been explored for managing hyperpigmentation associated with APP, and may help to fade the darker patches in some individuals.
Prognosis and Clinical Course of Atrophoderma of Pasini and Pierini
Atrophoderma of Pasini and Pierini typically follows a chronic course. The condition may remain stable for prolonged periods or slowly progress over years, with lesions potentially increasing in size and number, and sometimes coalescing to form larger affected areas. Eventually, the condition usually stabilizes.
While classically considered non-involuting, spontaneous improvement of lesions has been reported in some cases, although this is not the typical outcome. The long-term prognosis is generally benign in terms of overall health, as APP is primarily a cosmetic concern and does not usually affect systemic health, unless associated with conditions like systemic sclerosis, which require separate monitoring and management.
References:
- Liu S, Oliver F, Agnew K. An unusual infantile rash. Clin Exp Dermatol. 2018;43:835–8. doi:10.1111/ced.13541
- (And other standard dermatology textbooks and resources for Atrophoderma of Pasini and Pierini and differential diagnosis – to be added for a fully comprehensive article)
