Perigastrostomy infection caused by Mycobacterium abscessus in an immunocompetent patient.

Sir, Mycobacterium abscessus, a rapidly growing mycobac-terium (RGM), is an important environmental pathogen that can cause a broad spectrum of diseases. Foreign body-associated RGM infections are now receiving increasing emphasis because of the increased use of in-dwelling medical devices. Gastrostomy tube placement is a well-established and tolerated method to achieve feeding access in patients with dysphagia or aspiration. The gastrostomy tube may be placed surgically, endo-scopically or fluoroscopically. Percutaneous radiological gastrostomy (PRG) is performed under fluoroscopic guidance for tube insertion. We present here a rare cause of perigastrostomal infection due to M. abscessus in an immunocompetent patient. This case highlights the importance of including RGM infection in the differential diagnosis of recalcitrant peristomal infection. A 55-year-old man was admitted with a painful nodule surrounding the PRG port for the previous month. He had a medical history of nasopharyngeal carcinoma, which had been managed by operation and radio-therapy 20 years previously. No evidence of recurrence was noted and he had not received any treatment for cancer thereafter. Eight months prior to admission, fluoroscopically guided PRG was performed under amoxicillin-clavulanate coverage due to progressive dysphagia resulting from previous radiotherapy. The patient was in his usual state of health until one month before admission, when an erythematous, pigeon egg-sized, ill-demarcated, tender nodule with yellowish discharge and foul odour was noted around the gastro-stomy site. Laboratory investigations revealed a leuko-cyte count of 14.2 × 10 9 /l and an elevated C-reactive protein level of 6.76 mg/dl. Skin biopsy of the affected area demonstrated granulation tissue with acute and chronic inflammation. The acid-fast stain was negative. Cultures of the skin specimen for bacteria and fungi were negative. With suspected peristomal cellulitis, he was commenced on a 10-day treatment of intravenous amoxicillin-clavulanate, however, one week later, copious discharge of pus was observed from the biopsy wound (Fig. 1). Culture of the biopsy specimen yielded M. abscessus, which was also isolated from subsequent skin pus cultures in two sets. The antibiotic regimen was changed to clarithromycin (500 mg/day) and ciprofloxacin (1000 mg/day). After a 3-month treatment with antibiotics and without removal of the gastrostomy tube, the erythematous tender nodule disappeared. DISCUSSION M. abscessus, a member of Runyon group IV, is the most pathogenic and chemotherapy-resistant RGM. In 1953, it is first isolated from synovial fluid in a patient with post-traumatic arthritis and gluteal abscess (1). Since the 1980s, M. abscessus and M. chelonae have generally been regarded …