Pancreatic panniculitis is a rare disease contributing to widespread fat necrosis in patients with underlying pancreatic disorders. This entity was first described in 1883,1 but it was not until 1947 that it was reported in the English-language literature.2 Patients with pancreatitis infrequently develop extrapancreatic manifestations. It has been estimated that only 2% to 3% of patients worldwide with an underlying pancreatic disease develop cutaneous lesions.3 Patients who develop pancreatic panniculitis typically present with tender, edematous, erythematous to brown, subcutaneous nodules on the lower legs with the tendency for spontaneous ulceration. Lesions tend to exude a viscous, yellow-brown, oily substance that represents liquefactive necrosis of enzymatic fat in subcutaneous tissue. Cutaneous lesions may precede, occur simultaneously, or follow the development of an underlying pancreatic disorder. Rarely, patients may develop inflammatory arthritis secondary to intraosseous fat necrosis, completing the triad of findings diagnostic for panniculitis, pancreatitis, and polyarthritis (PPP) syndrome. Although the underlying pancreatic pathology may vary, roughly 80% of cases worldwide have acute/chronic pancreatitis or pancreatic carcinoma, most commonly acinar cell carcinoma.4-6 Less common pancreatic disorders include pancreatic pseudocyst, pancreatic divisum, and vascular pancreatic fistulas.7 Narváez et al8 found that of the 25 cases of PPP syndrome reported in the literature, 68% (17/25) were men, 32% (8/25) were women, 56% (14/25) were younger than 50 years, and 64% (16/25) had a history of prior or current alcohol abuse.
Case Report
A 68-year-old man with a history of hypertension, gastroesophageal reflux disease, chronic pancreatitis of unknown etiology, and arthritis presented to our clinic for evaluation of painful skin nodules on the lower legs of 8 months’ duration, in addition to joint pain and swelling of the metacarpophalangeal (MCP), metatarsophalangeal, and ankle joints. He had a history of numerous hospital admissions over the last 2 years for pancreatitis and was being managed by the rheumatology department for arthritic symptoms.
Physical examination revealed multiple 1- to 4-cm, ill-defined, erythematous to brown, subcutaneous nodules on the bilateral lower legs (Figure 1) and right inferomedial thigh that were tender to palpation. Marked erythema and edema of the MCP and metatarsophalangeal joints (Figure 2) and bilateral ankles were observed. Diffuse 2+ pitting edema was present in the bilateral lower extremities, along with areas of hyperpigmentation overlying resolving lesions.
Figure 1. Scattered 1- to 3.5-cm, ill-defined, erythematous to brown, subcutaneous nodules on the right lower leg.
Figure 2. Metatarsophalangeal joint swelling of the right hand with overlying erythema.
Laboratory data revealed an elevated lipase level (>16,000 U/L [reference range, 31–186 U/L]), amylase level (>4700 U/L [reference range, 27–131 U/L]), erythrocyte sedimentation rate (94 mm/h [reference range, 0–20 mm/h]), and C-reactive protein level (93.5 mg/L [0.08–3.1 mg/L]). The patient had more than 6 episodes of recurrent idiopathic pancreatitis over the last 2 years, though symptoms of abdominal pain were minimal to nonexistent. Liver function tests and alcohol, calcium, and triglyceride levels all were within reference range. Rheumatoid factor and antinuclear antibodies were negative.
Ultrasonography showed no evidence of cholelithiasis. Computed tomography of the abdomen and pelvis demonstrated a 1.8×1.4-cm hypodense lesion within the pancreatic head with calcifications and mild proximal pancreatic ductal dilatation (Figure 3). However, multiple magnetic resonance cholangiopancreatography examinations and endoscopic ultrasounds with fine-needle aspiration specimens were performed, all negative for malignancy. Computed tomography of the left ankle demonstrated evidence of bony cortical destruction in the lateral aspect of the posterior calcaneus. Bone biopsy specimens demonstrated mild chronic inflammation with no evidence of osteomyelitis. A serum uric acid level was found to be 4.4 mg/dL (reference range, 4.0–8.0 mg/dL) and a joint aspirate demonstrated turbid fluid with lipoid material and no evidence of crystals or organisms on culture. Furthermore, a 4-mm punch biopsy of a nodule on the right leg revealed extensive lobular and septal liquefactive adipocyte necrosis with scattered neutrophils and lymphocytes (Figure 4). Aggregates of fine granular basophilic material were observed with prominent adipocyte degeneration and calcification.
Figure 3. Transverse plane computed tomography of the abdomen and pelvis showed a hypodense lesion within the pancreatic head with calcification.
Figure 4. Lobular and septal liquefactive adipocyte necrosis with prominent ghost cells and fine basophilic material (H&E, original magnification ×10).
Symptomatic treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) along with intralesional, topical, and oral corticosteroids had proven ineffective in the management of this patient. He was subsequently referred to the surgery department for a pancreaticoduodenectomy (Whipple procedure) with notable improvement in pancreatic enzyme levels, lower leg subcutaneous nodules, and arthritis weeks after surgery.