Location
Philadelphia, PA
Start Date
1-5-2024 1:00 PM
End Date
1-5-2024 4:00 PM
Description
Introduction
Mycobacterium avium complex (MAC) infection in the spine is extremely rare, with its pathogenesis and epidemiology remaining poorly understood. Clinically, MAC infections commonly present with pulmonary, musculoskeletal, and disseminated disease. Manifestation of MAC infections, specifically disseminated disease to the spine, is uncommon in patients without human immunodeficiency virus or acquired immune deficiency syndrome.
Case Presentation
In December 2017, a 46-year-old immunocompetent man presented with severe lower back pain, right lower extremity pain, and a previous L5-S1 fusion. Imaging revealed pseudarthrosis at L5-S1 with halos around S1 screws. In March 2018, he underwent revision surgery with partial relief and began outpatient physical therapy. After seven months, his symptoms recurred. MRI indicated a fluid collection at L5-S1. In October 2018, he underwent irrigation and debridement (I&D), removal of hardware (ROH), and revision fusion. Initial cultures were negative, and empiric PO and IV antibiotics were initiated. In January 2019, he presented to the hospital with intractable low back back and right lower extremity numbness. Follow-up MRI in January 2019 suggested a recurrent fluid collection, leading to subsequent surgical intervention. Acid-fast bacterial (AFB), blood, wound, fungal cultures and a biopsy with gram stain were initially negative and empiric IV antibiotics were initiated. Post-op course was complicated by leukocytosis and hyperthermia. Repeat MRI revealed migration of the fluid collection into L5-S1 disc space. MRI one week later showed no improvements, which lead to a revision laminectomy, ROH, I&D, and drain placement. Four days post-op and one month after initial cultures, AFB cultures grew MAC. Treatment was initiated with Ethambutol, Rifampin, and Clarithromycin for twelve to eighteen months. At one year post-op, there was no sign of infection on updated imaging.
Discussion
This unique case underscores the rare possibility of MAC being linked to vertebral osteomyelitis, particularly in immunocompetent patients. MAC cultures are slow growing and can take up to six weeks to develop mature colonies making it challenging to initially diagnose. While our patient was immunocompetent, he had a past medical history of underlying lung disease, COPD, which is the most important risk factor for patients without HIV. It was hypothesized that the source of infection was secondary to a previous oral tooth abscess the patient subsequently developed, however, his multiple previous surgeries could have also been the source. Due to its rarity and long incubation times, accurate and early diagnosis of MAC represents a major challenge. Physicians should consider MAC in patients with non-responsive or recurrent osteomyelitis to prevent delayed diagnosis and significant adverse outcomes.
Embargo Period
6-17-2024
Included in
Mycobacterium Avium Complex-Associated Vertebral Osteomyelitis in an Immunocompetent Patient: A Case Report
Philadelphia, PA
Introduction
Mycobacterium avium complex (MAC) infection in the spine is extremely rare, with its pathogenesis and epidemiology remaining poorly understood. Clinically, MAC infections commonly present with pulmonary, musculoskeletal, and disseminated disease. Manifestation of MAC infections, specifically disseminated disease to the spine, is uncommon in patients without human immunodeficiency virus or acquired immune deficiency syndrome.
Case Presentation
In December 2017, a 46-year-old immunocompetent man presented with severe lower back pain, right lower extremity pain, and a previous L5-S1 fusion. Imaging revealed pseudarthrosis at L5-S1 with halos around S1 screws. In March 2018, he underwent revision surgery with partial relief and began outpatient physical therapy. After seven months, his symptoms recurred. MRI indicated a fluid collection at L5-S1. In October 2018, he underwent irrigation and debridement (I&D), removal of hardware (ROH), and revision fusion. Initial cultures were negative, and empiric PO and IV antibiotics were initiated. In January 2019, he presented to the hospital with intractable low back back and right lower extremity numbness. Follow-up MRI in January 2019 suggested a recurrent fluid collection, leading to subsequent surgical intervention. Acid-fast bacterial (AFB), blood, wound, fungal cultures and a biopsy with gram stain were initially negative and empiric IV antibiotics were initiated. Post-op course was complicated by leukocytosis and hyperthermia. Repeat MRI revealed migration of the fluid collection into L5-S1 disc space. MRI one week later showed no improvements, which lead to a revision laminectomy, ROH, I&D, and drain placement. Four days post-op and one month after initial cultures, AFB cultures grew MAC. Treatment was initiated with Ethambutol, Rifampin, and Clarithromycin for twelve to eighteen months. At one year post-op, there was no sign of infection on updated imaging.
Discussion
This unique case underscores the rare possibility of MAC being linked to vertebral osteomyelitis, particularly in immunocompetent patients. MAC cultures are slow growing and can take up to six weeks to develop mature colonies making it challenging to initially diagnose. While our patient was immunocompetent, he had a past medical history of underlying lung disease, COPD, which is the most important risk factor for patients without HIV. It was hypothesized that the source of infection was secondary to a previous oral tooth abscess the patient subsequently developed, however, his multiple previous surgeries could have also been the source. Due to its rarity and long incubation times, accurate and early diagnosis of MAC represents a major challenge. Physicians should consider MAC in patients with non-responsive or recurrent osteomyelitis to prevent delayed diagnosis and significant adverse outcomes.