Panniculitis - Reviewing the basics

The most common cause of primary septal panniculitis is erythema nodosum. The clinical and microscopic features causing this disease are well known to the experienced dermatologist.

The most common etiologic agents in erythema nodosum include infections (e.g. group A beta hemolytic strep, deep fungal and viral), drugs (e.g. oral contraceptives and sulfonamides), inflammatory bowel disease, sarcoidosis, pregnancy and malignancy.

Dr. Robinson-Bostom says that, "We have found new associations concerning the etiologies in erythema nodosum. These include hepatitis C and HIV infections, all trans retinoic acid, echinacea herbal therapy, celiac disease, as well as carcinoid syndrome."

The list of causes of primary lobular panniculitis is long and include sclerema neonatorum (rare), pancreatic fat necrosis, subcutaneous fat necrosis of the newborn, alpha-1 antitrypsin deficiency, post-steroid-, cold-, foreign body/factitial-, cytophagic histiocytic-, and neutrophilic panniculitis.

"In pancreatic fat necrosis, primary lobular panniculitis occurs in 2 to 3 percent of all patients with pancreatic disease and the panniculitis may be the only clinical presentation. Also, this panniculitis has been seen with acute and chronic pancreatitis, pancreatic acinar, as well as with sulindac therapy. What's new here is that this panniculitis has been also been associated with primary HIV infections, liver carcinoma, neuroendocrine carcinoma, pancreatic acinar cell cystadenocarcinoma, and post traumatic pancreatitis," Dr. Robinson-Bostom explains.

Secondary panniculitis occurs in a multitude of disease states including vascular diseases (e.g. leukocytoclastic vasculitis, polyarteritis nodosa, and thrombophlebitis - all of which are septal), fibrosing diseases (e.g. morphea/scleroderma, eosinophilic fasciitis, and nephrogenic fibrosing dermopathy - which are septal), granulomatous diseases (e.g. subcutaneous granuloma annulare, rheumatoid nodule, necrobiotic xanthogranuloma, necrobiosis lipoidica, and sarcoidosis - most of which are lobular), infectious diseases (e.g. fungal, bacterial, viral and infestations - all of which are septal), and malignant diseases (e.g. lymphoma, leukemia, and malignant histiocytosis - all of which are lobular).

Combined septal and lobular panniculitis is known to be caused by nodular vasculitis or erythema induratum and lupus erythematosus profundus or connective tissue panniculitis. Dr. Robinson-Bostom says that recently, it has also been linked with Sjögren's syndrome and hepatitis C infections.

According to Dr. Robinson-Bostom, in all cases of panniculitis, the treatment simply consists of treating the underlying cause, if known (e.g. stop a medication, treat an infection). The affected area must be rested and elevated, and compression hosiery may be used if applicable. Systemic corticosteroids (oral or intravenous) may be administered to settle the inflammation. Also, antibiotics such as tetracycline or hydroxychloroquine could be used as well for its anti-inflammatory effect. She says that painful lesions can be treated with anti-inflammatory medications such as aspirin, ibuprofen and diclofenac. DT

Hear Dr. Leslie Robinson-Bostrom's full presentation in FOC808 from 12:15 to 1:45 p.m. today.