FELV Infection and Wavy Whiskers

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Bicipital Tendon Injury and Treatment in Dogs

Biceps tendon (BT) pathology is a common cause of lameness in dogs and may result from primary BT issues or complications like supraspinatus tendinopathy. Treatment strategies have traditionally involved surgical transection which, while potentially alleviating discomfort, changes the normal anatomy and joint mechanics, affecting the biceps brachii muscle's role in shoulder stability. 

Conservative treatment (CTx) is generally preferred before considering surgery, but there's no consensus on what CTx should involve. Varying opinions exist between veterinary surgeons (VS), rehabilitation therapists (RTh), and those with dual certification (DB) in surgery and sports medicine/rehabilitation (VSMR). 

The study aimed to discern treatment approach differences among these groups regarding BT pathology. It was thought that VS might devalue the BT’s role in stability and favor surgery more than RTh, and that DB would have intermediate views. 

Survey findings showed that VS do indeed attribute less importance to the BT in shoulder stability and are more likely to propose surgery as the initial treatment. RTh and DB showed a preference for CTx. The consensus among all groups was that for a healthy BT, or when less than 20% torn, conservative treatment should be tried first. If the BT is 75% torn, surgery might be the best option, but CTx could still be considered. 

The survey revealed a lack of enthusiasm for long-term NSAID use due to concerns about delayed tendon healing, and intra-articular corticosteroids were considered inappropriate for long-term treatment aiming for tissue repair. Intratendinous corticosteroid injections were discouraged, with a preference for minimally invasive surgery if tendon necrosis is the goal. 

Rehabilitation practices included therapeutic exercise and staged return to activity, as well as treatments like ESWT, regenerative medicine, and photobiomodulation. There's insufficient evidence to support the use of therapeutic ultrasound, PEMF, or acupuncture in treating BT issues, and while manual therapy may offer comfort, it doesn't aid tendon healing. 

Lane, D. M., Pfeil, D. v., & Kowaleski, M. P. (2023). Synthesis of surgeon and rehabilitation therapist treatment methods of bicipital tenosynovitis in dogs allows development of an initial consensus therapeutic protocol. Journal of the American Veterinary Medical Association https://doi.org/10.2460/javma.23.08.0461 

Bottom line — An integrated approach to conservative therapy based on exercise and activity restriction is essential.

FELV Infection and Wavy Whiskers

This study explores a novel physical symptom in domestic cats—wavy whiskers (WW)—and its association with Feline leukemia virus (FeLV) infection. FeLV is a retrovirus that affects cats globally and is typically diagnosed through blood tests for antigens. Researchers conducted various tests on 358 cats, of which 56 had wavy whiskers, to investigate the potential link between this trait and FeLV infection. 

The study found a significant correlation between wavy whiskers and the presence of FeLV, as cats with WW were more likely to test positive for the virus. This suggests that wavy whiskers could be an external indicator of FeLV infection. However, the sensitivity of using WW to detect FeLV was somewhat low at 68.4%, meaning that not all infected cats exhibit this symptom. 

Through blood tests and multivariate analysis, the researchers also noted that FeLV is typically associated with immunosuppression, anemia, and lymphoma in cats. The virus is mainly found in lymphocytes and monocytes in the blood and can be transmitted through body fluids like saliva, tears, and urine. Interestingly, FeLV antigens were abundant in the epithelial cells of the cats' proboscis tissue, indicating these cells as a source of viral shedding through saliva. 

The study further identified viral antigens in the follicular epithelial cells of the whiskers, specifically the viral core protein p27, which was also surprisingly found in the skeletal muscle fibers of some infected cats. This unexpected discovery points to a wider distribution of the FeLV receptor in the body, including skeletal muscles. 

Histopathological examinations showed that FeLV-infected cats did not have neoplastic changes, but virus-like particles were observed in the epithelium of sinus hair follicles without causing cellular damage. This suggests that the whiskers' wavy changes are not due to damage to the follicles but could be a result of the virus's long-term effects. 

The study's findings also raised the possibility of localized FeLV infection in the proboscis tissue because some cats with WW were serologically negative for FeLV. Moreover, in rabies and other virus studies, viral presence in the follicular walls has been associated with the targeting of specific cells, like Merkel cells. 

In conclusion, the research presents the first-known association between whisker morphology and viral infection in cats. Wavy whiskers are significantly associated with FeLV infection, and while they are not a definitive diagnostic tool, they could potentially serve as an external marker for the disease. Further research is required to understand the exact mechanisms behind the wavy changes in whiskers and the full clinical implications of this phenotype in FeLV-infected cats. 

Morishita M, Sunden Y, Horiguchi M, Sakoya H, Yokogawa M, Ino H, Une S, Kawata M, Hosoido T, Morita T. Wavy changes in the whiskers of domestic cats are correlated with feline leukemia virus infection. BMC Vet Res. 2023 Mar 4;19(1):58. doi: 10.1186/s12917-023-03610-7. PMID: 36871053; PMCID: PMC9985215. 

 Bottom Line - Interesting phenotypic change to be looking for…

Nocita and Surgical Site Infections

The study in question explored the incidence of surgical site infections (SSIs) in dogs and cats that underwent gastrointestinal surgery and were administered Nocita, an FDA-approved liposomal bupivacaine, at the time of surgical closure. The research aimed to determine if using Nocita increased the risk of SSIs and if there was a difference in the types of bacteria isolated from these infections compared to those not treated with Nocita. The overall findings revealed that the administration of Nocita did not result in higher SSI rates when compared to patients who did not receive the drug. In fact, the SSI rates were lower in animals that received Nocita. 

The study also showed that most SSIs were caused by bacteria typically found in the gastrointestinal tract, such as E. coli and Enterococcus. Interestingly, the presence of multidrug-resistant (MDR) bacteria was not significantly different between the animals that received Nocita and those that did not. The majority of SSIs occurred in dogs that had surgeries to remove foreign bodies, suggesting a possible increased risk of infection in these procedures due to greater contamination. 

However, the study had several limitations, including its retrospective nature, lack of standardized administration of Nocita, variations in postoperative lavage, and potential bias in patient selection for Nocita administration. Additionally, the lack of routine anaerobic culture tests and the reliance on owner reports and follow-up visits for SSI diagnosis could have led to underreporting of infections. 

In conclusion, the study indicated that Nocita is not associated with an increased risk of SSIs in dogs and cats undergoing gastrointestinal surgery and does not contribute to the growth of more MDR bacteria. Further research, particularly prospective clinical trials, is needed to confirm these findings and explore the effects of Nocita on a broader range of surgeries and its potential impact on MDR infections. 

Andrews, C., Williams, R., & Burneko, M. (2023). Use of liposomal bupivacaine in dogs and cats undergoing gastrointestinal surgery is not associated with a higher rate of surgical site infections or multidrug-resistant infections. Journal of the American Veterinary Medical Association https://doi.org/10.2460/javma.23.08.0463 

Bottom line — It does not appear to cause an increased risk of post-surgical infections.

Just putting things in perspective …