Case 6 -

Eosinophilic Panniculitis Secondary to Intravenously Administered Antibiotic Therapy James W. Patterson, M.D.

Panniculitis characterized by large numbers of eosinophils has been highlighted in the literature since the mid 1980s. However, it is best not to consider this finding representative of a specific disorder, since the causes, clinical presentations, and histopathology (other than the presence of eosinophils) can vary considerably. Lesions certainly present as subcutaneous nodules, but other clinical manifestations include urticarial lesions, plaques, purpura, pustules, and ulcers. Involvement of upper and lower extremities, trunk, face and scalp has been reported. The presentation can closely mimic that of erythema nodosum, or there can be a background of Wells' syndrome, atopy, vasculitis, infection, malignancy, arthropod bites, polyarteritis nodosa, glomerulonephritis, or sarcoidosis. In their 1986 review of the subject, Winkelmann and Frigas noted that six patients had psychiatric illness; four of these were drug dependent, and injection granuloma was suspected. Since then, cases have been linked to gabexate mesilate (a synthetic protease inhibitor) IV drip infusion for acute pancreatitis, self-inflicted autoinjection of "farming products", and the use of apomorphine (a dopamine agonist) in Parkinson's disease. We have previously encountered panniculitis with eosinophils in patients receiving vaccine therapy as part of a melanoma treatment protocol, and in the present case, intravenous antibiotic therapy had been administered in the affected extremity. The clinical appearance of the panniculitis otherwise provides few clues as to the etiology of the condition, with the possible exception of gnathostomiasis, which typically presents with migratory lesions. Case 6 - Slide 1 Click to view with ImageScope Click to view with a Web-Based Viewer Microscopically, the panniculitis may be predominantly septal, lobular, or mixed. Aside from the large numbers of eosinophils, other changes are relatively nonspecific. Flame figures can be seen in the cases associated with Wells' syndrome, but this finding is not necessarily diagnostic, as occasional flame figures can be encountered in unrelated dermatoses with numerous eosinophils. Organisms can be identified in cases associated with gnathostomiasis. In those lesions associated with injection, especially the self-inflicted cases, one may find evidence of a needle tract, a "central nidus" of subcutaneous inflammation, accompanying fat necrosis or changes of sclerosing lipogranuloma, or foreign material. Special stains for organisms are also recommended as part of the workup of these cases. References: Adame J, Cohen PR: Eosinophilic panniculitis: diagnostic considerations and evaluation. J Am Acad Dermatol 1996; 34: 229-234. Gomez Rodriguez N, Ortiz-Rey JA: Auto-induced eosinophilic panniculitis: a diagnostic dilemma. An Med Interna 2001; 18: 635-637. Nakayama F: Panniculitis with eosinophilic infiltration due to gabexate mesilate (FOY): possibility of allergic reaction. J Dermatol 1997; 24: 235-242. Winkelmann RK, Frigas E: Eosinophilic panniculitis: a clinicopathologic study. J Cutan Pathol 1986; 13: 1-12.