Arthritis and meniscal tears

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Meniscal Damage and Arthritis in Dogs

This retrospective study aimed to assess the relationship between meniscal pathology and degenerative joint disease in dogs undergoing TPLO surgery for cranial cruciate ligament rupture. The study found a higher prevalence of meniscal tears in dogs with severe osteoarthritis, particularly in cases of complete cranial cruciate ligament rupture compared to partial rupture. Sporting and mixed-breed dogs had a higher frequency of meniscal tears, and increasing age was positively associated with meniscal tears. Arthrotomy diagnosed more meniscal tears compared to arthroscopy. The study also highlighted the potential contribution of meniscal dysfunction to the progression of osteoarthritis. Meniscal tears were not associated with the duration of lameness, contrary to some previous studies. The normal aging process and postoperative complications were identified as risk factors for meniscal injuries. The study acknowledged limitations such as its retrospective nature, variability in grading osteoarthritis, surgeon skill and preferences, missed diagnosis during surgery, and insufficient record keeping. The findings contribute to understanding meniscal injuries in dogs undergoing TPLO surgery, aiding in diagnosis, management, and prevention of complications.

Fung C, Ficklin M, Okafor CC. Associations between meniscal tears and various degrees of osteoarthritis among dogs undergoing TPLO for cranial cruciate ligament rupture. BMC Res Notes. 2023 Mar 13;16(1):36. doi: 10.1186/s13104-023-06307-0. PMID: 36915203; PMCID: PMC10012516. 

Bottom line — Severity of injury is not as important as the injury itself.

UPC and Sample Storage in Cats

The urinary protein:creatinine ratio (UPC) is an important measurement used to diagnose and monitor chronic kidney disease (CKD) in cats. This ratio helps determine the severity of proteinuria (protein in the urine) and guides treatment decisions. Cats with CKD typically exhibit low-level proteinuria (UPC < 1.0), whereas moderate to marked proteinuria is more common in humans and dogs with kidney disease. Several factors can affect UPC results in cats, and it's crucial to understand these factors for accurate diagnosis and monitoring. However, there is limited research on the (pre)analytical factors that can influence UPC measurements in cats. Studies in humans and dogs have shown high imprecision and poor accuracy of automated assays for measuring urinary protein levels. In dogs, UPC values can vary depending on the laboratory, and misclassification can occur near the thresholds for different proteinuria stages. Studies comparing UPC results among commercial laboratories and different measurement techniques in cats are also lacking. Another important consideration is the storage of urine samples before analysis. In clinical practice, it's not always possible to analyze samples immediately, and they may need to be shipped or stored at different temperatures. Short-term storage at room temperature or in the refrigerator (up to 7 days) does not significantly affect UPC results in cats. However, long-term storage (6-12 months) can lead to clinically relevant changes in UPC, particularly when stored at -24°C. It's preferable to store urine samples long-term at -80°C to minimize the impact on UPC measurements. In terms of interlaboratory variability, this study found that the choice of laboratory does not significantly affect absolute UPC values in cats. However, there was only moderate agreement among laboratories when classifying proteinuria according to the International Renal Interest Society (IRIS) guidelines. This lack of agreement can lead to differences in therapeutic and prognostic categorization of cats with proteinuria. It's important for clinicians to be aware of potential misclassifications and consider laboratory-specific reference intervals when interpreting UPC values. To improve standardization and minimize interlaboratory variation, it's suggested to introduce UPC measurement standardization in veterinary medicine. Additionally, reporting UPC values with two decimal places and using uniform reporting methods can facilitate comparison between laboratories. In conclusion, the choice of laboratory can affect the classification of proteinuria in cats, emphasizing the importance of using the same laboratory for monitoring individual cats. Short-term storage of urine samples does not significantly impact UPC results, but long-term storage can lead to clinically relevant changes, with better stability observed at -80°C. Further studies are needed to explore the biological variability of proteinuria in cats and aid in clinical decision-making. 

Mortier, F, Daminet, S, Duchateau, L, Demeyere, K, Meyer, E, Paepe, D. Effect of laboratory and sample storage factors on urinary protein:creatinine ratios and clinical decision making in cats. J Vet Intern Med. 2023; 37( 3): 1038- 1046. doi:10.1111/jvim.16696 

Bottom line — Short-term storage (up to 7 days) does not affect results

Rapid Diagnosis of Bacteriuria

The study evaluated the performance of a rapid immunoassay (RIA) called RapidBac Vet for detecting bacterial urinary tract infections (UTIs) in dogs. The aim was to assess the sensitivity and specificity of the RIA test and its agreement with urine culture results, as well as to determine the association between clinical signs and both RIA test and culture outcomes. The results showed that the RIA had a high sensitivity of 90.0% and specificity of 95.2% for detecting bacteriuria (bacterial presence in urine) at a threshold of ≥103 CFU/mL. The agreement between the RIA and urine culture was substantial, indicating reliable results. However, it should be noted that the RIA cannot provide information about antimicrobial susceptibility, so urine culture and susceptibility testing are still recommended after a positive RIA result. The study also found that the RIA performed well in predicting the presence of gram-negative bacteria in single-species infections but was unable to distinguish gram-negative bacteria in polymicrobial infections or detect gram-positive isolates in a single urine sample. The prevalence of positive urine cultures in the study was higher than in previous studies, likely due to the inclusion criteria selecting dogs more likely to have bacteriuria. Clinical signs such as malodorous urine were positively associated with positive culture and RIA results, but caution is advised due to the subjective nature of owner-reported signs. The RIA test could be a valuable tool for clinicians in guiding their decision to initiate empirical therapy while awaiting culture results. It provides reliable and rapid results at the point-of-care, potentially improving antimicrobial stewardship by avoiding unnecessary antibiotic use when the RIA is negative. Further studies are needed to assess clinical signs, signalment, and culture outcomes in a larger population of dogs. Overall, the study demonstrated that the RIA test is a quick and user-friendly assay with good sensitivity and specificity, which could aid veterinarians in diagnosing UTIs and making treatment decisions for dogs with clinical signs suggestive of a urinary tract infection. 

Sutter, CM, Dear, JD, Fine, JR, et al. Evaluation of a rapid immunoassay for bacteriuria in dogs. J Vet Intern Med. 2023; 37( 3): 1015- 1020. doi:10.1111/jvim.16684 

Bottom line — Quick and user-friendly way to diagnose bacteria but still need C/S.

Just putting things in perspective …