History: A 70-year-old woman who had for five years been treated with tumour necrosis factor (TNF)-a-inhibitors for rheumatoid arthritis was admitted because of treatment-refractory oral ulcerations and persisting considerable soft-tissue swelling over the left maxilla.
Investigations and diagnosis: Multiple mucosal biopsies from the left maxillary sinus revealed necrotizing granulomatous inflammation suspicious of mycobacterial infection. This was subsequently confirmed in concurrent microbiological cultures and ultimately identified as Mycobacterium bovis. This species of the mycobacterium tuberculosis complex has in recent times rarely been seen in clinical practice in Germany. On further questioning the patient reported that she had been treated for "lung disease" as a schoolgirl.
Treatment and course: The patient was isolated and quadruple therapy with isoniazide (INH), rifampin (RMP), ethambutol (EMB) and pyrazinamide (PZA) was initiated. Rapid improvement of her condition occurred within two weeks. When microbiological sub-typing using 16s-RNA sequencing had confirmed M. bovis, PZA was replaced by moxifloxacin.
Conclusion: When investigating the cause of treatment-refractory infections and ulcerations, particularly among immunosuppressed patients, consideration should always be given to mycobacterial infections. Detailed and targeted history-taking is vital.
Georg Thieme Verlag KG Stuttgart, New York.