Clinical manifestations and outcomes of musculoskeletal nontuberculous mycobacterial infections.

To investigate the clinical manifestations and outcomes of musculoskeletal (MSK) nontuberculous mycobacterium (NTM) infections. This study was a retrospective cohort study using the Siriraj Hospital database from 2005 to 2017. Enrolled were all patients aged 15 or older who had an MSK infection with NTM identified in synovial fluid, pus, or tissue by an acid-fast bacilli stain, culture, or polymerase chain reaction. Of 1529 cases who were diagnosed with NTM infections, 39 (2.6%) had an MSK infection. However, only 28 patients met our inclusion criteria. Their mean age (SD) was 54.1 (16.1) years, and half were male. Of this cohort, 25% had previous musculoskeletal trauma, 18% prior bone and joint surgery, 14% prosthetic joint replacement, and 11% HIV infection. The median symptom duration (IQR) was 16 (37.4) weeks. The most common MSK manifestation was arthritis (61%), followed by osteomyelitis (50%), tenosynovitis (25%), and spondylodiscitis (14%). The most common organism was M. abscessus (18%), and M. kansasii (18%), followed by M. intracellulare (14%), M. marinum (14%), M. fortuitum (7%), and M. haemophilum (7%). In addition to medical treatment, most patients underwent surgery (82%), comprising debridement, osteotomy, prosthesis removal, and amputation, while 18% received only medical treatment. The treatment outcomes were complete recovery in 46%, improvement with some residual disability and deformities in 29%, and death in 3.6%. Musculoskeletal NTM infections were uncommon. Most patients had underlying joint disease or were immunocompromised hosts. Surgical management, as an adjunct to medical therapy, was necessary.

The role of avian reoviruses in turkey tenosynovitis/arthritis.

Turkey arthritis reovirus (TARV) has been isolated from the gastrocnemius tendons and tibiotarsal joint fluid of lame male turkeys >12 weeks old in the Midwest. Two experiments were conducted to compare the pathogenicity in turkeys of three TARVs (TARV-MN2, TARV-MN4 and TARV-O'Neil), one turkey enteric reovirus (TERV strain MN1) and one chicken arthritis reovirus (CARV strain MN1). Two hundred microlitres of virus were inoculated by the oral, intratracheal, or footpad route into 6-day-old poults placed in isolator units. Poults were necropsied at 1 and 4 weeks post infection in Experiment 1, and at 2 and 4 weeks post infection in Experiment 2. Reovirus was detected by reverse transcription-polymerase chain reaction and virus isolation in tendons of TARV-inoculated poults at 1, 2 and 4 weeks post infection. TARV-O'Neil and TARV-MN2 were detected in tendons of sentinal birds at 1 and 4 weeks and 1 week p.i., respectively. In general, TARVs produced lymphocytic tenosynovitis of the gastrocnemius and digital flexor tendon sheaths without inflammation of the tendons proper. In Experiment 1, poults inoculated with TARV-MN2 and TARV-O'Neil had significantly higher gastrocnemius tendon inflammation scores, as determined by histology, than those inoculated with TERV-MN1 or CARV-MN1. In Experiment 2, poults inoculated with TARV-MN2 and TARV-O'Neil had significantly higher gastrocnemius tendon inflammation scores than those inoculated with TARV-MN4 and virus-free medium (negative control group). Koch's postulates was fulfilled when TARV-MN2 and TARV-O'Neil were re-isolated from tendons of poults that had originally been challenged with either of these viruses. Results of these experiments indicate that TARVs have a unique ability to induce gastrocnemius tenosynovitis in turkeys and that administration of TARV-O'Neil through the oral or intratracheal route is a reproducible model to study pathogenesis of TARV infection.

What is the likelihood that a horse treated for septic digital tenosynovitis will return to its previous level of athletic function?

REASONS FOR PERFORMING STUDY: Septic digital tenosynovitis is a serious problem in the horse, with a poor prognosis being reported for recovery. HYPOTHESIS: The occurrence of septic digital tenosynovitis would significantly reduce the likelihood of a horse returning to its previous level of athletic function. METHODS: Medical records of 90 horses treated for septic digital tenosynovitis were reviewed. Data retrieved included age, sex, location of inciting cause of sepsis, time from onset of clinical signs to presentation for treatment, and whether the horse survived to be discharged. Long-term outcome was determined through telephone questionnaires. Univariate analyses of categorical variables were conducted for each outcome. RESULTS: Overall, 87.8% of horses (79/90) survived to be discharged from the hospital. Only one factor examined was shown to have a significant effect on outcome. A delay of 1-7 days between onset of clinical signs and presentation for treatment reduced significantly the likelihood of the horse surviving to be discharged from the hospital. Of the horses discharged from the hospital, long-term follow-up was available for 72 horses, with 54.2% (39/72) returning to their previous level of athletic function. CONCLUSIONS: Only approximately 50% of horses treated for septic digital tenosynovitis returned to their previous level of athletic function following resolution of synovial sepsis. POTENTIAL RELEVANCE: Accurate figures allowing a realistic assessment of the athletic future of a horse following treatment for septic digital tenosynovitis are of value to both the owner and treating veterinarian.