Pannus refers to an abnormal growth of tissue that can manifest in various parts of the body. This condition is characterized by its unique development, common sites, and underlying causes. Understanding pannus is important for recognizing its signs and pursuing appropriate management strategies.
Understanding Pannus
Pannus is an abnormal layer of fibrovascular or granulation tissue. This tissue develops over a surface, often in response to chronic inflammation. It appears as a reddish, fleshy overgrowth with new blood vessels.
Though non-cancerous, this tissue can expand in a tumor-like fashion. It tends to invade or grow over existing structures, causing damage. Composed of immune cells, fibroblasts, and macrophages, it has invasive and destructive potential.
Locations Where Pannus Develops
Pannus can form in several distinct areas of the body. Each location presents with varied appearances and effects.
Joints
In joints, particularly in conditions like rheumatoid arthritis, pannus develops from the inflamed synovial membrane, the joint lining. This tissue grows over and erodes articular cartilage and bone within the joint capsule, releasing enzymes that break down these structures. The affected joints may feel spongy or boggy, and individuals often experience pain, stiffness, and reduced mobility. Unchecked, it can lead to joint deformities and impaired function.
Eyes
Corneal pannus involves the growth of fine blood vessels and tissue onto the normally clear cornea of the eye. This appears as a whitish, pink, or brown discoloration, often starting at the edge of the cornea and extending inward. These blood vessels and tissue obstruct light, causing hazy or blurry vision. Untreated, severe corneal pannus can lead to scarring and impaired sight.
Abdomen
Abdominal pannus refers to an overhanging fold of excess skin and fatty tissue in the lower abdomen. It is associated with obesity or significant weight loss. It appears as an “apron” of tissue hanging from the abdomen, sometimes extending to the thighs. This excess skin can lead to hygiene challenges, skin irritation, rashes, and sores in the folds due to moisture trapping and friction.
Underlying Causes of Pannus
Pannus formation is driven by inflammatory processes or excess tissue. Specific conditions and factors contribute to its development in different parts of the body.
Autoimmune Diseases
Autoimmune diseases are a primary cause of pannus, especially in joints. Rheumatoid arthritis (RA) is a notable example, where the immune system mistakenly attacks the body’s own tissues, specifically the synovium lining the joints. This sustained immune response causes chronic inflammation and synovial tissue proliferation, forming destructive pannus that erodes cartilage and bone. Other inflammatory arthritic conditions, such as psoriatic arthritis, can also lead to pannus formation, though it is generally less severe than that seen in RA.
Chronic Inflammation or Infection
Persistent inflammation or long-standing infections can contribute to pannus formation. In the eye, for instance, chronic irritation or infection, such as from ill-fitting contact lenses or keratitis, can lead to corneal pannus. The body’s prolonged inflammatory response stimulates new blood vessel and tissue growth on the cornea, an attempt to heal that results in abnormal pannus.
Obesity
Excessive adipose tissue and chronic low-grade inflammation from severe obesity contribute to abdominal pannus. The volume of fat and skin creates large, overhanging folds. This excess tissue can become a site of chronic inflammation, causing skin irritation and other complications. While not inflammatory like joint pannus, its physical burden and associated inflammation contribute to its persistence.
Diagnosis and Treatment of Pannus
Managing pannus involves recognizing its signs and employing targeted medical and surgical interventions. Treatment depends on its specific location and underlying cause.
Joint pannus can cause pain, swelling, stiffness, and a decrease in joint function. Corneal pannus may lead to blurry vision, eye redness, and light sensitivity. Abdominal pannus can result in skin irritation, rashes, and discomfort due to friction and moisture in skin folds.
Diagnosis involves a physical examination to assess the affected area. Imaging techniques like X-rays, MRI, or CT scans visualize the pannus and assess damage to underlying structures, especially in joints. A biopsy may confirm its nature and rule out other conditions.
Treatment is tailored to the pannus type and cause, with managing the underlying condition being paramount. For joint pannus from rheumatoid arthritis, medications like anti-inflammatory drugs, DMARDs, or biologics reduce inflammation and slow disease progression. Corneal pannus treatment may involve topical anti-inflammatory drops, such as steroids or cyclosporine, to reduce vessel growth. Abdominal pannus management involves addressing obesity through lifestyle changes and skin care to prevent irritation.
Surgery may be considered when pannus causes significant problems or doesn’t respond to medication. For joint pannus, a synovectomy (surgical removal of inflamed synovial tissue) can alleviate pain and improve joint function. Abdominal pannus can be surgically removed through a panniculectomy, which excises excess skin and fat. For severe corneal pannus affecting vision, laser treatment or a corneal transplant may clear the cornea. Supportive care, like physical therapy for joint mobility or specialized skin care for abdominal pannus, also plays a role.