Lichenoid Dermatitis in Association With Pancrealipase

Abstract

Introduction: Lichenoid drug reactions to drugs are rare but well reported. Pancreatic enzyme preparations are used in managing malabsorption disorders. The most common side effects are headache, abdominal pain, neck/ear pain, nasal congestion and lymphadenopathy. Rare side effects include allergic reactions, anaphylaxis, hives and pruritis. We describe a case of lichenoid dermatitis (LD) in association with pancrealipase. To the best of our knowledge, this side effect has never been reported in association with pancrealipase. Case presentation: A 67-year-old man (no past medical history) with newly diagnosed pancreatic cancer underwent Whipple's procedure. After the surgery he was started on pancreatic enzyme replacement with pancrealipase. A few weeks after patient noticed rash on the legs. The rash was pruritic, papular with purplish tinge; grouped together over the legs (figure 1). There were also isolated lesions on the forearm that were disc like plaques, purplish and itchy (figure 2). Punch biopsy of one of the lesion on the right calf demonstrated dermal lymphoid aggregate with eosinophils (figure 3). History was not suggestive of any other medication intake.Figure 1Figure 2Figure 3Clinical course: Discontinuation of pancrealipase (as that was the only medication he was taking) led to resolution of the rash. However, discontinuation exacerbated the malabsorption symptoms and hence pancrealipase was restarted. This eventually led to recurrence of the rash. Patient was symptomatically managed with 10 mg of cetirizine, each time with meals along with pancrealipase and 2 tablets of 10 mg cetirizine at bedtime. This eventually resulted in symptomatic control and relief from itching. Discussion: Pancrealipase is porcine derived pancreatic amylase, pancreatic lipase and chymotrypsin. Latency period between the exposure to offending drug and appearance of lesions of LD varies from days to months to years. It is easily diagnosed because of the purplish tinge of the polygonal papules. It is caused by inflammation of the epidermis and is associated with intense pruritis. Differential diagnosis of LD includes lichen planus, atopic dermatitis and chronic cutaneous lupus erythematous. Conclusion: We demonstrate a rare case of LD in association with pancrealipase. However given the necessity of pancrealipase in the patient after Whipple's procedure and to minimize drug reaction; symptomatic control and relief from itching was achieved with anti-histamines.