Increased time between diagnosis and surgery in slipped capital femoral epiphysis results in increased radiographic deformity.

PURPOSE: Previous work has examined the impact of delay of diagnosis in slipped capital femoral epiphysis (SCFE) but not the impact of delay in treatment after radiographic diagnosis. Due to requirements for long distance transportation from less developed regions for many of our patients, our hospital was able to study variation in time between diagnosis and surgery for SCFE, as related to slip severity. METHODS: This is a retrospective review of patients treated for SCFE between 2005 and 2014 at a tertiary care paediatric hospital. Demographics, time between diagnosis and surgery, radiographic deformity (Southwick angle), postoperative complications and need for further surgery were variables of interest. Statistical analysis included Pearson and Spearman rank correlations and chi-squared tests. RESULTS: The study sample included 147 hips (119 patients). Mean time between radiographic diagnosis and surgery was 20.9 days (sd 46, 0 to 321). The mean Southwick angle (SA) at the time of surgery was 31.9˚ (sd 19.6˚, 1° to 83˚). There was a significant relationship between increased delay and increased SA (0.34, p < 0.001). Increased SA was correlated with need for future significant surgery (0.27, p < 0.01).Patients from less-developed regions, with barriers to timely care, had moderate and severe deformity (SA) (p < 0.01), and required significant further surgery more often than SCFE patients from the local population (p < 0.01). CONCLUSION: The unique referral environment of our hospital provided an opportunity to examine traditional recommendations for treating SCFE promptly after radiographic diagnosis. Delay in treatment is correlated with increased radiographic deformity. LEVEL OF EVIDENCE: III.

In vitro susceptibility of porcine respiratory pathogens to tilmicosin.

Bacterial isolates obtained from swine with various clinical diseases were tested for susceptibility to tilmicosin by minimum inhibitory concentration (MIC) and Kirby-Bauer disk diffusion tests using National Committee on Clinical Laboratory Standards methodology. The tilmicosin MIC90 was < or =0.125 microg/ml for Erysiopelothrix rhusiopathiae, < or = 1 microg/ml for Haemophilus parasuis isolates, 8 microg/ml for Actinobacillus suis and Pasteurella multocida type A, 16 microg/ml for toxigenic and nontoxigenic P. multocida type D, 64 microg/ml for Bordetella bronchiseptica, and >128 microg/ml for Staphylococcus hyicus and Streptococcus suis. The results of disk diffusion testing matched well with the MIC results for each pathogen. This in vitro survey of tilmicosin activity against various swine isolates suggests that further clinical evaluation of tilmicosin in swine may be warranted for disease associated with E. rhusiopathiae, H. parasuis, and A. suis but not B. bronchiseptica, S. suis, or S. hyicus.

Comparison of Pasteurella spp. simultaneously isolated from nasal and transtracheal swabs from cattle with clinical signs of bovine respiratory disease.

Twenty-four matched pairs of isolates of Pasteurella haemolytica and three matched pairs of isolates of Pasteurella multocida were isolated by using a nasal swab and a transtracheal swab from individual calves with clinical signs of bovine respiratory disease. The identity of each matched pair was confirmed biochemically and serologically. The similarity of the isolates obtained from a nasal swab and from a transtracheal swab was compared by using ribotyping and antibiotic susceptibility analyses. Although the calves were sampled only once with a nasal and a transtracheal swab, when both samples were bacteriologically positive the nasal swab identified the same bacterial species as the transtracheal swab 96% of the time. The nasal swab isolate was genetically identical to the transtracheal isolate in 70% of the matched pairs. Six different ribotypes were observed for the P. haemolytica isolates, while only one ribotype was observed for the limited number of P. multocida isolates. Of the six P. haemolytica ribotypes, two ribotypes predominated. All the paired isolates displayed similar susceptibility to ceftiofur, erythromycin, tilmicosin, trimethoprim-sulfamethoxazole, and florfenicol, with some minor variations for ampicillin and spectinomycin. These results suggest that a nasal swab culture can be predictive of the bacterial pathogen within the lung when the isolates are from an acutely ill animal and can be used to determine antibiotic susceptibility.

Efficacy of a bovine Staphylococcus aureus vaccine using interleukin-2 as an adjuvant.

The purpose of this study was to examine the efficacy of a vaccination protocol using recombinant bovine interleukin-2 (rBoIL-2) as an adjuvant with a Staphylococcus aureus vaccine. Holstein dairy cows were immunized with a S. aureus vaccine in conjunction with either saline solution (n = 3), Freund's incomplete adjuvant (FIA; n = 3) or rBoIL-2 (n = 3). Whey and serum were analysed for antibody titer to specific S. aureus antigens. Isolated blood mononuclear cells (BMC) were examined for their ability to proliferate and to produce interleukin-2 (IL-2) and interferon (IFN) after either mitogenic or antigenic stimulation in vitro. Efficacy of the vaccination protocols was assessed by challenging experimental animals intramammarily with 100 colony forming units of S. aureus. Regardless of treatment, all cows exhibited similar serum antibody titers to S. aureus pseudocapsule. Cows treated with saline exhibited a significant increase in serum alpha-toxin antibody titer when compared to levels observed in FIA and rBoIL-2-treated cows. However, cows receiving rBoIL-2 treatment exhibited significantly higher lacteal pseudocapsule antibody titer compared to the other adjuvant groups. Administration of rBoIL-2 did not enhance BMC proliferative responses to the mitogens concanavalin A (ConA), phytohemagglutinin (PHA), pokeweed mitogen (PWM) or interleukin-2 (IL-2) when compared to FIA or saline treated cows. Although cows receiving rBoIL-2 treatment exhibited enhanced cytokine production upon antigenic stimulation, efficacy of the vaccination protocol was inferior compared to the protection offered by saline treatment.