An unusual cutaneous manifestation in a patient with cystic fibrosis

A 24-year-old woman affected by cystic fibrosis (CF) with pulmonary and pancreatic involvement was referred at our gastroenterology department because of sustained increased bowel movements (4-5 per day) despite pancreatic enzyme replacement therapy. The patient denied abdominal pain and on physical examination she did not present abdominal masses. Laboratory examinations showed little increase of reactive C protein (3 mg/dL; normal value, <0.8) and mild anemia (hemoglobin, 11.2 g/dL; mean corpuscular volume, 90 fL). Fecal calprotectin was normal and stool culture, and research for parasites were negative. A recent abdominal magnetic resonance imaging (MRI), performed because of CF, was also normal. We decided to further increase pancreatic enzyme replacement therapy and undergo a brief course of ciprofloxacin (500 mg twice a day for 7 days), obtaining only a small decrease in bowel movements. A few weeks after treatment adjustment, the patient presented a curious skin manifestation, characterized by erythematous papules that progressively become confluent to form scaly plaques on the lower limbs (FigureA). A skin biopsy was performed showing noncaseating granulomas of tuberculoid type, with Langerhans-type multinucleated giant cells in the dermis and subcutaneous tissue ( FigureB; stain: Hematoxylin and eosin; original magnification, ×4; FigureC; stain: H&E; original magnification, ×20).