Stasis Dermatitis:

Stasis dermatitis, also known as stasis eczema, is a chronic inflammatory skin condition that typically affects the lower legs due to poor venous circulation, or chronic venous insufficiency. This condition commonly occurs in individuals with associated risk factors such as varicose veins, long-term swelling (edema), skin discoloration, and lipodermatosclerosis. The primary symptom is chronic inflammation in the lower extremities, with patches of red, scaly, and itchy skin. While stasis dermatitis is most commonly observed on the legs, rare cases have been documented in the upper limbs, particularly in patients with artificial arteriovenous fistulas or congenital vascular malformations.

Epidemiology and Risk Factors

Stasis dermatitis is linked to chronic venous insufficiency, which has varying prevalence rates worldwide. Chronic venous insufficiency affects approximately 1% to 40% of females and 1% to 17% of males, with the incidence rising significantly with age. For example, a study in Turkey reported stasis dermatitis in 6.2% of hospitalized patients aged 65 and older. The condition is more common in populations with established risk factors for venous disease, which include:

  • Age and Gender: Incidence rates are higher in older adults and tend to be slightly more common in females.

  • Genetic Predisposition: A family history of venous insufficiency increases risk.

  • Occupational Factors: Long periods of standing can aggravate or contribute to chronic venous insufficiency.

  • Obesity: Excess weight contributes to venous hypertension and worsens venous disease.

  • History of Deep Vein Thrombosis (DVT): DVT can damage venous valves, contributing to chronic venous issues.

  • Heart Failure and Hypertension: These conditions can exacerbate venous pressure, aggravating symptoms.

Pathophysiology

The underlying cause of stasis dermatitis is chronic venous hypertension. This heightened pressure in the venous system results from several factors, such as valve dysfunction, venous obstruction, or failure of the calf muscle pump mechanism. When venous valves are compromised, blood can flow backward into the superficial venous system, turning it into a high-pressure network. This pressure triggers several microcirculatory changes in the dermis, including dilated capillaries and increased permeability, leading to edema, fibrin deposition, hemosiderin accumulation, and hyperplasia of small blood vessels.

Histopathological studies show that in stasis dermatitis, the skin’s capillaries undergo thickening, and there is an increase in macrophages, T lymphocytes, and mast cells, which contribute to chronic inflammation. Additionally, there is upregulation of matrix metalloproteinases, enzymes involved in the breakdown of extracellular matrix components. These cellular changes support the hypothesis that inflammation from venous hypertension plays a critical role in the development and persistence of stasis dermatitis.

Clinical Presentation

Stasis dermatitis is generally a late-stage manifestation of chronic venous disease and is classified as stage C4 in the CEAP (Clinical-Etiology-Anatomy-Pathophysiology) classification system for chronic venous disorders. It presents as red, scaly, and itchy patches or plaques, often accompanied by swelling in the legs. The medial ankle is the most affected region, but symptoms may spread from the foot up to the knee.

In acute cases, stasis dermatitis can present with significantly inflamed, moist plaques, vesicles, and crusting. Bacterial or fungal infections may occur, leading to impetiginized crusts or pustules. Due to the redness, inflammation, and sometimes unilateral distribution of lesions, stasis dermatitis can be misdiagnosed as cellulitis. Chronic stasis dermatitis often leads to darkening of the skin (hyperpigmentation) from hemosiderin deposits and may result in skin thickening from chronic scratching.

Diagnostic Evaluation

Stasis dermatitis is typically diagnosed through clinical examination. Key diagnostic indicators include skin lesions on the lower legs, a history of venous insufficiency, and signs of other venous disease, such as varicose veins and pitting edema.

In cases where the diagnosis is unclear, a skin biopsy may be performed to rule out other skin conditions such as allergic contact dermatitis, asteatotic eczema, or skin cancers. A biopsy typically reveals hyperkeratosis, parakeratosis, acanthosis, and mild spongiosis, alongside hemosiderin-laden macrophages and an increased number of small blood vessels in the dermis.

Additional Tests
When diagnosing stasis dermatitis, additional vascular studies, including color Doppler ultrasound, may be beneficial. Doppler studies can evaluate venous reflux and blood flow obstructions, helping confirm chronic venous insufficiency in patients without clear symptoms. Patch testing for contact dermatitis may also be recommended if patients experience worsening symptoms despite appropriate skin care.

Differential Diagnosis

Differentiating stasis dermatitis from similar skin conditions is crucial for proper management. Conditions that may resemble stasis dermatitis include:

  • Cellulitis: This bacterial infection of the skin typically presents unilaterally with redness, swelling, warmth, and tenderness, along with systemic symptoms like fever.

  • Asteatotic Eczema: Also known as eczema craquelé, this condition appears as dry, cracked, and itchy skin, often occurring in older adults during winter.

  • Contact Dermatitis: Often occurs due to irritants or allergens and may overlap with stasis dermatitis in patients using topical medications or dressings.

  • Psoriasis and Lichen Simplex Chronicus: These conditions can present with red, scaly plaques but lack the venous insufficiency signs associated with stasis dermatitis.

  • Dermatophyte Infections (Tinea Corporis): Fungal infections can mimic stasis dermatitis, particularly when accompanied by scaling and pruritus. Fungal culture or KOH testing may help in distinguishing these infections.

Complications

Stasis dermatitis patients are at higher risk for several complications due to underlying venous issues and skin barrier disruptions:

  1. Contact Sensitization: Chronic use of topical treatments can lead to contact allergies in stasis dermatitis patients. Fragrances, preservatives, and topical antibiotics are common allergens.

  2. Autosensitization (Autoeczematization): Patients may develop a secondary, pruritic rash on areas not initially affected by stasis dermatitis.

  3. Superinfection: Skin breakdown from scratching or inflammation increases the risk of bacterial infections like impetigo, often caused by Staphylococcus aureus or Streptococcus pyogenes.

  4. Lipodermatosclerosis: This chronic condition results from long-term inflammation and fibrosis, leading to hardened, darkened skin around the ankles. It may also present with painful swelling and an “inverted champagne bottle” appearance.

  5. Acroangiodermatitis: Sometimes called "pseudo-Kaposi sarcoma," this rare vascular condition presents as purple-brown plaques and is triggered by venous stasis.

Conclusion

Stasis dermatitis is a common skin disorder linked to chronic venous insufficiency and typically affects the lower legs. Diagnosis is based on clinical findings, history of venous disease, and characteristic skin changes. While many cases of stasis dermatitis can be managed with topical treatments and lifestyle adjustments, accurate diagnosis is essential for distinguishing it from other skin conditions. In cases of persistent or severe symptoms, referral to a vascular specialist is recommended to address underlying venous disease. Early management can help reduce the risk of complications, such as infections and skin thickening, and improve patient outcomes