INTRODUCTION: Mycobacterium abscessus is a rapid growing NTM that rarely causes pulmonary disease in immunocompetent individuals. We present an unusual case of a young, immunocompetent woman with a protracted and complicated clinical course of pulmonary NTM infection.
CASE PRESENTATION:A 39 years old female presented with a two month history of right sided pleuritic chest pain, cough and brown sputum, weight loss and night sweats. Chest imaging showed ground glass opacities with an apical cavity, and she was managed empirically for Community acquired pneumonia with vancomycin, ceftriaxone and metronidazole. To rule out tuberculosis, mycosis and malignancy, video bronchoscopy was performed and broncho alveolar lavage performed, that grew MSSA and it was negative for HIV and tuberculosis. She was treated with cefazolin and discharged on a month of cephalexin. 48 hours after discharge her Acid fast smear turned positive, and she was contacted by our infectious disease team and initiated on four drug regimen for pulmonary tuberculosis. While on treatment, her NAAT came back negative for tuberculosis and positive for mycobacterium abscessus. She started getting worse despite treatment, and came to the ER with worsening dyspnea and chest pain. New imaging revealed new bony erosions of the adjacent first and second ribs with pathological fractures and worsening bilateral infiltrates. The entire disease was attributable to the isolated Mycobacterium chelonae-abscessus group and she was urgently transferred to a tertiary care for multi-disciplinary treatment. On 2 months follow up, she is stable on outpatient IV antibiotic therapy with iminipenem, tigecycline and amikacin with a plan for prolonged therapy.DISCUSSION: Mycobacterium chelonae-abscessus group, a non-tuberculous mycobacterium (NTM), with prevalence across different regions of USA between 2% to 18%, naturally found in water and soil. It is known to cause outbreaks of skin and soft tissue infections in immunocompetent hosts. It is known to cause outbreaks of skin and soft tissue infections in immunocompetent hosts. Very rarely does this rapidly growing non-tuberculosis mycobacterium cause infection in an immunocompetent host. Furthermore, when it affects the lungs, results in bronchiectasis, nodules and consolidation.CONCLUSIONS: This case highlights the rapidly progressive course of Mycobacterium abscessus/chelonae complex in an unusual host-an immunocompetent female with no comorbidities, with the only pertinent history being that of smoking. Our case is atypical in presentation of its pulmonary involvement, as our patient had a cavitatory lesion, which is seen much less commonly. The British Thoracic Society recommends an aggressive multi-antibiotic approach, and treatment should be based on susceptibility panels, which should include clarithromycin, amikacin, cefoxitin amongst others.
