Chlamydiae and atherosclerosis: can psittacine cases support the link?

Atherosclerosis is a common disease in pet birds, particularly in psittacines. Little is known about the role of risk factors predisposing birds to this disease. In our study, we tried to detect chlamydiae in formalin-fixed and paraffin-embedded atherosclerotic tissue from 103 pet birds to clarify their role in atherosclerosis. Methods used were polymerase chain reaction (PCR), sequencing, and immunohistochemistry. Histopathologic examination served to classify the extent of atherosclerotic lesions. In the PCR, 4 (3.9%) of 103 cases, all of them with advanced stages of atherosclerosis, were positive. Subsequent sequence analysis revealed high identities (94%-100%) with Chlamydophila psittaci in three cases. Interestingly, two of these birds came from C. psittaci-infected populations. Because of the low incidence (3.9%), the occurrence only in advanced stages, and the association with C psittaci-infected avian populations, a causal relationship between chlamydiae and atherosclerosis in pet birds is rather improbable.     

Endoscopic assessment and treatment of lesions of the deep digital flexor tendon in the navicular bursae of 20 lame horses

REASONS FOR PERFORMING STUDY: Clinical lesions of the deep digital flexor tendon and navicular bone are being reported with increasing frequency. However, the role of direct visualisation by navicular bursoscopy in the diagnosis and management of such injuries has not been explored. HYPOTHESIS: Navicular bursoscopy: 1) corroborates information obtained from other, noninvasive imaging modalities; 2) allows direct visualisation of lesions unidentified by other diagnostic modalities; 3) provides further information on morphology of lesions; and 4) permits minimally invasive surgical access to lesions. METHODS: The case records of all horses that underwent diagnostic navicular bursoscopy for the investigation of lameness admitted to 2 referral clinics (the Royal Veterinary College and Reynolds House Referrals) were evaluated retrospectively. Follow-up information was obtained by telephone questionnaire. RESULTS: Twenty-three bursae were examined endoscopically in 20 horses. Tears of the deep digital flexor tendon were seen in all horses (22 bursae). In 8 bursae, cartilage lesions were also present and in one bursa this was the only abnormal finding. Computed tomography and low field magnetic resonance imaging predicted tendon lesions in most cases, but failed to identify cartilage damage. Greater than 6 month follow-up information was available for 15 animals of which 11 were sound and 9 had returned to preoperative levels of performance. CONCLUSION: Lameness localised to the foot may result from tears of the deep digital flexor tendon and/or navicular fibrocartilage loss. Navicular bursoscopy allows comprehensive evaluation of these changes and also permits appropriate lesion management. POTENTIAL RELEVANCE: The diagnostic information obtained from and therapeutic options offered by bursoscopy justify its use in horses with clinical findings localising lameness to the navicular bursa.     

Mesenchymal stem cell therapy in equine musculoskeletal disease: scientific fact or clinical fiction?

The goal in the therapeutic use of mesenchymal stem cells (MSCs) in musculoskeletal disease is to harness the regenerative nature of these cells focussing on their potential to grow new tissues and organs to replace damaged or diseased tissue. Laboratory isolation of MSCs is now well established and has recently been demonstrated for equine MSCs. Stem cell science has attracted considerable interest in both the scientific and clinical communities because of its potential to regenerate tissues. Research into the use of MSCs in tissue regeneration in general reflects human medical needs, however, the nature, prevalence and prognosis of superficial digital flexor tendonitis has put equine veterinary science at the forefront of tendon regeneration research. Much has been investigated and learnt but it must be appreciated that in spite of this, the field is still relatively young and both communities must prepare themselves for considerable time and effort to develop the technology into a highly efficient treatments. The promise of functional tissue engineering to replace old parts with new fully justifies the interest. At present, however, it is important to balance the understanding of our current limitations with a desire to progress the technology.