Septic Mycobacterium Avium Intracellulare Extensor Tenosynovitis of the Wrist

Abstract

Mycobacterium avium intracellulare (MAI) infections of the hand, wrist, and upper extremity are rare, but potentially devastating atypical mycobacterial infections that can affect tendon, bone, and other soft tissues of the musculoskeletal system. We present an immunocompromised patient presenting with acute swelling and pain in the dorsum of the hand and wrist that underwent a wrist extensor tenosynovectomy with intraoperative cultures revealing infection with MAI. The patient developed severe progression of the infection with osteomyelitis of the distal forearm and carpal bones, multiple subsequent extensor tendon ruptures, and dorsal skin necrosis. The infection was eradicated with a combination of surgical treatment and antibiotic therapy. The case is discussed in context of the prior scant literature of infectious tenosynovitis of the hand, wrist, and upper extremity caused by MAI. This case report and literature review outline recommendations for diagnosis and effective treatment of MAI.

Keywords: atypical mycobacterial infection; mycobacterium avium intracellulare; septic extensor tenosynovitis.

Fig. 1

( A and B ) Axial T2 images of the right wrist magnetic resonance imaging (MRI) with contrast at the level of the distal radius ( A ) and proximal carpal row ( B ) revealing severe multicompartment tenosynovitis most extensively involving fourth extensor compartment with splitting of the tendons and lesser involvement of the second and third extensor compartments. On the upper right of B , a 1.8 cm × 1.9 cm mass consistent with a rice body is seen (red arrow).

Fig. 2

Tenosynovium of extensor digitorum communis (EDC) showing palisading necrotizing granulomatous inflammation with multinucleated giant cells.

Fig. 3

( A – C ) Coronal images ( A and B ) of computed tomography (CT) scan with contrast revealing extensive bony erosions of the distal forearm, carpus, and base of the metacarpals consistent with osteomyelitis. Axial image ( C ) of CT scan revealing significant dorsal and volar erosion of cortices of distal ulna as well as volar erosion of cortices of distal radius.

Fig. 4

Clinical photo of dorsum of right wrist revealing erythema, skin breakdown, and extrusion of extensor tendon rupture at two and a half months from initial debridement.

Fig. 5

Clinical photo of dorsum of right wrist severe dorsal soft tissue loss and worsening erythema and drainage at 6 days after second debridement.

Fig. 6

Axial T2 images of the right wrist at the level of the distal radius ( A ) and proximal carpal row ( B ) revealing significant improvement in extensor tenosynovitis.

Fig. 7

Clinical photo of dorsum of right wrist 1 year postoperatively demonstrating completely healed soft tissue defect.