« Back to Inflammatory Disorders

Panniculitis

»What is panniculitis?
»Name the various types of panniculitis. How are they classified?
»What is erythema nodosum?
»What is the pathogenesis of erythema nodosum?
»List some of the common underlying conditions associated with erythema nodosum.
»How should a biopsy of erythema nodosum be obtained?
»What are the characteristic microscopic features of erythema nodosum?
»How is erythema nodosum treated?
»What is nodular vasculitis?
»What causes nodular vasculitis?
»Describe the microscopic features of nodular vasculitis.
»What is the differential diagnosis of nodular vasculitis?
»How should nodular vasculitis be treated?
»What are the clinical features of lupus panniculitis?
»Describe the microscopic features of lupus panniculitis.
»What is the significance of diagnosing lupus panniculitis?
»Are sclerema neonatorum and subcutaneous fat necrosis of the newborn the same thing?
»How similar are the microscopic features of sclerema neonatorum and subcutaneous fat necrosis of the newborn?
»Why do these disorders occur in neonates and infants?
»What is pancreatic fat necrosis?
»Are there any characteristic histopathologic features of pancreatic fat necrosis?
»What is the role of a-1 antitrypsin deficiency in the development of panniculitis?
»Name some types of trauma that can produce panniculitis.
»Which infectious organisms can produce panniculitis?
»Describe the role of malignancy in producing panniculitis.
»What is lipodystrophy?
»What is lipoatrophy?
»What is lipohypertrophy?
»Discuss the approach to use when attempting to diagnose an “unknown” case of panniculitis.

 
 
 

What is pancreatic fat necrosis?


Pancreatic fat necrosis showing classic involvement of the lower legs. Note the desquamation on the patient’s right posterior leg, suggesting that spontaneous discharge is likely.
Fig. 19.6 Pancreatic fat necrosis showing classic involvement of the lower legs. Note the desquamation on the patient’s right posterior leg, suggesting that spontaneous discharge is likely.
Subcutaneous nodules occur on the legs (Fig. 19-6) or elsewhere associated with acute or chronic pancreatitis or pancreatic carcinoma. Visceral fat may also be involved. Although immune mechanisms may play a role in producing this form of fat necrosis, the weight of evidence favors the effects of circulating pancreatic lipase, amylase, and trypsin on subcutaneous fat. The frequent co-occurrence of arthritis with joint fluid analysis revealing free fatty acids is a clinical reminder of the systemic effects of these pancreatic enzymes. Treatment is directed toward the underlying pancreatic disease.

Preiss JC, Faiss S, Loddenkemper C, et al: Pancreatic panniculitis in an 88-year-old man with neuroendocrine carcinoma, Digestion 66:193–196, 2002.