2 Case Reports in Medicine Figure 1: Multiple violet skin lesions in the right lower extremity of the patient. Pitting edema of the ankle and foot is also demonstra- ted. The inlet depicts one of the lesions, where an oriﬁce leading to a pus collection is shown. Staphylococcus aureus. Two-week treatment with doxycycline resulted in no clinical improvement. The diagnosis of pyo- derma gangrenosum (with possible bacterial contamination) was considered and treatment with inﬂiximab initiated in a classical induction scheme (0–2–6 wks). Before starting ther- apy with inﬂiximab, a tuberculin skin test was performed and reported negative, whereas a chest X-ray was unremarkable. Ten days after the second infusion of inﬂiximab, the patient noticed worsening of the skin lesions along with high fever (38.7◦C) and was admitted to our hospital. Clinical examination revealed an obese patient (BMI: 32) with temperature of 37.7◦C. Inspection of the lower extremities showed multiple, painless, erythroviolet, round, and clearly delineated nodular lesions, 2–5 cm in size, which were localized in the lower right leg and foot (Figure 1). There was seropurulent discharge from some of the lesions. Laboratory investigations revealed mild leukocytosis (WBC: 11,900 k/μL, P: 85%, L: 7%), with elevated erythrocyte sedi- mentation rate (60 mm/hr, normal range 0–20 mm/hr) and C-reactive protein (12.6 mg/dL, normal range 0–5 mg/dL) with no abnormalities on biochemical and urine tests. Colonoscopy revealed endoscopic features consistent with quiescent ulcerative colitis, which was conﬁrmed by histological examination of colon biopsies that showed absence of active inﬂammation and signs of chronic injury with disturbed mucosal architecture. As the patient experienced persistent fever (37.8 to 38.2◦C), we performed extensive search for infectious agents. Blood, urine, and stool cultures as well as chest X-rays were repeatedly negative. Tuberculin skin test was negative and CT-scan of the lower abdomen was unremarkable. MRI scan of the lower right limb and three-phase bone scintigraphy with 99mTc-MDP revealed signs consistent with inﬂammation of the skin and subcutaneous tissue but no evidence of bone involvement or abscess formation. A skin biopsy showed ﬁndings consistent with a granulomatous inﬂammatory process of the skin, without necrosis. Pus was collected from one of the draining lesions. Direct microscopic examination after Ziehl-Neelsen staining was positive for acid-fast bacilli (Figure 2). Cultures of the purulent material on both blood agar and Lowenstein media Figure 2: Ziehl-Neelsen staining of pus obtained from a draining lesion reveals multiple acid-fast bacilli. Figure 3: Photograph taken 6 months after treatment shows heal- ing of the skin lesions with complete cessation of discharge and resi- dual discoloration. yielded a rapidly growing, nontuberculous mycobacterium. Treatment was initiated with intravenous cefoxitin 3 g qid, clarithromycin 500 mg bid, and amikacin 1 g qd. Two weeks later the patient was signiﬁcantly improved with cessation of fever and diminishing of cutaneous lesions. Following the identiﬁcation of the microorganism as Mycobacterium chelonae in a reference laboratory and susceptibility testing, she was discharged home on clarithromycin 500 mg bid for an additional six months. Administration of inﬂiximab and azathioprine was terminated and corticosteroids rapidly tapered and discontinued. Upon several follow-up visits, the patient remained afebrile and the cutaneous lesions were gradually eliminated (Figure 3). 3. Discussion The present case illustrates the diﬃculties in managing dermatological manifestations in patients with IBD. The diﬀerential diagnosis should include not only those skin conditions that occur more frequently in IBD (most notably erythema nodosum and pyoderma gangrenosum) but also treatment-associated lesions [3]. Among the latter, skin infections should always be considered in patients who receive immunosuppressive regimens, particularly in the