Table of Contents
What Is Panniculitis?
Panniculitis is a group of illnesses that cause inflammation of the subcutaneous fat. Erythema nodosum is a common type of panniculitis. Although panniculitis can have a wide range of causes, most cases share a similar clinical presentation. It usually manifests as painful, pigmented pimples on the skin.
Panniculitis frequently starts in the calves and shins, before moving on to the thighs and upper body. Various factors, such as autoimmune diseases, infections, and low temperatures, can cause it.
A skin biopsy confirms the diagnosis because different causes have different microscopic characteristics. After forming, it usually goes away in six weeks without leaving any scars. Sometimes, there may occasionally be a faint stain that looks nearly like a bruise that eventually disappears.
What Are the Rare Forms of Panniculitis?
Although many types of panniculitis, such as erythema nodosum, are relatively common and have a good record of diagnosis, a range of uncommon variations can be difficult to diagnose and treat because of their unusual appearances and underlying causes. Knowing such rare forms of panniculitis is essential for providing correct diagnosis and appropriate treatment.
1) Nodular Nonsuppurative Panniculitis:
Nodular nonsuppurative panniculitis, also called Weber-Christian disease, is an uncommon skin condition characterized by painful, sensitive lumps beneath the skin's surface. These lumps typically cause the fat layer beneath the skin to become inflamed. What specifically causes nodular nonsuppurative panniculitis is uncertain.
These nodules are normally found on the legs and trunk and can cause acute illness, muscle soreness, abdominal pain, and weight loss. They typically have a length of 10 to 20 millimeters. These symptoms could go away in a few days or weeks and then come back weeks, months, or even years later.
Diagnosis - A careful clinical evaluation is necessary to diagnose NNP. This evaluation includes a comprehensive physical examination, a detailed medical history, and, at times, a skin biopsy for conclusive evidence. The main features of histopathology include lipomembranous alterations, fat necrosis, mixed inflammatory infiltration with lymphocytes, histiocytes, and occasionally large cells, and lobular panniculitis with vasculitis.
Treatment - Corticosteroids frequently offer quick symptom alleviation and are considered a cornerstone treatment. In steroid-resistant cases, immunosuppressive medications such as Cyclosporine, Azathioprine, and Methotrexate may be used. NSAIDs and other anti-inflammatory medications can help control less severe symptoms. In addition to certain medication therapies, supporting measures, including applying cold compresses and elevating the afflicted limbs, help reduce symptoms.
2) Pancreatic Panniculitis:
Pancreatic panniculitis is a rare form of panniculitis. It is associated with pancreatic disorders such as pancreatitis or pancreatic cancer. It results from pancreatic disorders and causes inflammation of the subcutaneous tissue, mainly on the lower extremities. It appears as red, painful nodules on the legs and, less frequently, on the arms and torso. Systemic signs of this condition include fever, weight loss, and stomach aches.
Diagnosis - Diagnosis of pancreatic panniculitis includes a comprehensive examination and skin biopsy. From a histopathological perspective, pancreatic panniculitis primarily exhibits lobular panniculitis with notable necrosis of adipocytes. Ghost adipocytes, a classic feature of this condition, are necrotic adipocytes with basophilic and coarsely granular particles in the cytoplasm due to calcium deposits.
Treatment - The primary goal of pancreatic panniculitis treatment is to address the underlying pancreatic disease, which results in a complete or nearly full remission of symptoms. While corticosteroids can help with some symptoms, immunosuppressants or NSAIDs are typically ineffective in treating skin lesions.
3) Lipodermatosclerosis:
Lipodermatosclerosis is a chronic panniculitis linked to venous insufficiency. It is often noticed in people with chronic venous hypertension. Sclerodermaformis hypodermitis and sclerosing panniculitis are other names for lipodermatosclerosis. The main feature is the development of indurated, hyperpigmented plaques that resemble an upside-down champagne bottle in the lower legs. People in their middle or later years are commonly affected with lipodermatosclerosis. It is uncertain what specifically causes lipodermatosclerosis. The underlying cause of venous disease may involve factors such as obesity, venous incompetence, and venous hypertension.
Diagnosis - Clinical diagnosis is made based on clinical observation. Doppler investigations may confirm underlying venous insufficiency. A biopsy is rarely advised because it increases the risk of poor wound healing. Characteristic histology findings include fibrinoid necrosis of fat lobules, thickening of the dermis and subcutaneous septa, and mixed septal and lobular panniculitis.
Treatment - Leg elevation and elastic compression stockings can be used to treat venous insufficiency as part of treating lipodermatosclerosis. Corticosteroids, both topical and systemic, can be provided for inflammation and pain relief.
4) Lupus Panniculitis:
Lupus panniculitis, also known as lupus erythematosus profundus, is a chronic inflammatory disease. Patients with systemic lupus erythematosus (SLE) or discoid lupus erythematosus (DLE) may experience this condition. The symptoms of lupus panniculitis are firm, deep nodules on the face, arms, and upper thighs. Skin alterations indicative of scarring or atrophy can be seen in the overlying skin. It is unknown what causes lupus specifically. It is believed that tissue of the panniculus, located beneath the skin's surface, is attacked by the immune system, resulting in inflammation and the eventual development of lupus panniculitis symptoms.
Diagnosis - The histological analysis of a lesioned skin specimen is the gold standard for diagnosing it. The histopathology results include peri-adnexal inflammation, lobular panniculitis with lymphocytic infiltration, hyaline necrosis of fat lobules, and interface dermatitis.
Treatment - Antimalarial drugs, such as Hydroxychloroquine, are frequently successful for treating lupus panniculitis. Topical corticosteroids, especially Clobetasol propionate, can be used for acute flares.
5) Erythema Induratum:
Erythema induratum, or Bazin's disease, is a rare form of panniculitis often linked to tuberculosis. However, it is now known to occur without a history of tuberculosis, although it was formerly thought to be the tuberculous equivalent of nodular vasculitis. It mostly affects middle-aged women and manifests as tender, erythematous nodules on the posterior portions of the legs. Ulceration and discharge can be noticed in long-term situations.
Diagnosis - Based on a combined evaluation of the results of the skin biopsy and clinical examination, the diagnosis of EI is made. A skin biopsy reveals langhans large cells, granulomatous inflammation, and lobular panniculitis with vasculitis and caseous necrosis.
Treatment—Anti-tuberculous therapy (ATT) is necessary when tuberculosis is present. Corticosteroids and immunosuppressive medications may be considered for symptom management.
Conclusion:
Panniculitis is a broad spectrum of inflammatory diseases affecting the subcutaneous fat. Rare forms of panniculitis pose diagnostic and treatment challenges to the clinician because of their distinct clinical presentations and etiologies. Extensive knowledge of the clinical characteristics and histological findings is essential for an accurate diagnosis and successful therapy.
