Hans D. Westermeyer

Effects of dietary lysine supplementation on upper respiratory and ocular disease and detection of infectious organisms in cats within an animal shelter.

OBJECTIVE To determine within a cat shelter effects of dietary lysine supplementation on nasal and ocular disease and detection of nucleic acids of Chlamydophila felis, feline calicivirus (FCV), and feline herpesvirus (FHV-1). ANIMALS 261 adult cats. PROCEDURES Cats were fed a diet containing 1.7% (basal diet; control cats) or 5.7% (supplemented diet; treated cats) lysine for 4 weeks. Plasma concentrations of lysine and arginine were assessed at the beginning (baseline) and end of the study. Three times a week, cats were assigned a clinical score based on evidence of nasal and ocular disease. Conjunctival and oropharyngeal swab specimens were tested for FHV-1, FCV, and C felis nucleic acids once a week. RESULTS Data were collected from 123, 74, 59, and 47 cats during study weeks 1, 2, 3, and 4, respectively. By study end, plasma lysine concentration in treated cats was greater than that in control cats and had increased from baseline. There was no difference between dietary groups in the proportion of cats developing mild disease. However, more treated cats than control cats developed moderate to severe disease during week 4. During week 2, FHV-1 DNA was detected more commonly in swab specimens from treated versus control cats. CONCLUSIONS AND CLINICAL RELEVANCE Dietary lysine supplementation in the amount used in our study was not a successful means of controlling infectious upper respiratory disease within a cat shelter. Rather, it led to increases in disease severity and the incidence of detection of FHV-1 DNA in oropharyngeal or conjunctival mucosal swab specimens at certain time points.

Long-term evaluation of the use of Ahmed gonioimplants in dogs with primary glaucoma: nine cases (2000-2008).

OBJECTIVE To evaluate the outcome and describe the complications associated with use of an Ahmed gonioimplant in the treatment of glaucoma in dogs. DESIGN Retrospective case series. ANIMALS 9 client-owned sighted dogs (median age, 9 years) with primary glaucoma. Procedures-Medical records of dogs with primary glaucoma that underwent unilateral gonioimplant placement (in 2000 through 2008), during which a temporalis muscle fascia graft (n = 8) or porcine intestinal submucosa (1) was used to cover the implant tube as it exited the globe, were reviewed. All dogs were treated with mitomycin C in the conjunctival pocket intraoperatively and with tissue plasminogen activator immediately after surgery; 1% prednisolone acetate was applied to the implanted eye daily until failure of the implant. Medical intervention or additional surgery was performed when intraocular pressures (IOPs) were > 20 mm Hg or progressively increasing values were detected. RESULTS After gonioimplant placement, IOP was controlled for a variable period in all dogs. Subsequently, IOP exceeded 20 mm Hg in 7 dogs (median postoperative interval, 326 days). Median interval to vision loss despite interventional surgery was 518 days (range, 152 to 1,220 days). Surgical intervention was necessary in 4 dogs to maintain satisfactory IOP. Implant extrusion attributable to conjunctival dehiscence or necrosis occurred in 4 dogs. At 365 days after surgery, 8 dogs retained vision, and 5 dogs retained vision throughout follow-up. CONCLUSIONS AND CLINICAL RELEVANCE In dogs with medically refractory primary glaucoma, placement of a gonioimplant appears to be effective in maintaining vision.

Breed predisposition to congenital alacrima in dogs

OBJECTIVE To evaluate the clinical characteristics and breed predisposition of congenital alacrima in dogs. Animals studied Dogs with congenital keratoconjunctivitis sicca. PROCEDURES A search of the medical records of the University of Tennessee Veterinary Teaching Hospital from 1974-2005 and the University of California-Davis Veterinary Teaching Hospital from 1986-2006 for dogs under 1 year of age with a diagnosis of keratoconjunctivitis sicca (KCS) was performed. These cases were further reviewed for dogs with a Schirmers tear test I of <or= 5 mm/min before 6 months of age, with no known causes for KCS, which did not respond to appropriate KCS therapy; these cases were considered to have congenital alacrima. These breeds were compared to all other breeds using the Fishers exact test with correction for multiple comparisons. RESULTS Congenital alacrima was identified in 19 dogs representing 11 breeds and mixed breeds. Yorkshire Terriers and Bedlington Terriers were statistically overrepresented compared to reference populations (P < 0.01 and P = 0.04, respectively). CONCLUSIONS Yorkshire terriers are significantly at risk for congenital alacrima compared to other breeds. The significance of the increase in congenital alacrima in Bedlington Terriers in this study may not be clinically relevant and may be due to the small total number of dogs of this breed that presented to the both hospitals. Based on the poor response to therapy in humans with congenital alacrima, it may be prudent to offer guarded prognoses for KCS in juvenile Yorkshire terriers.

Assessment of viremia associated with experimental primary feline herpesvirus infection or presumed herpetic recrudescence in cats.

OBJECTIVE To detect feline herpesvirus type 1 (FHV-1) in blood of cats undergoing experimental primary herpetic disease or with spontaneous disease presumed to be caused by FHV-1 reactivation. ANIMALS 6 young specific-pathogen-free (SPF) cats and 34 adult cats from a shelter. PROCEDURES Conjunctiva and nares of SPF cats were inoculated with FHV-1, and cats were monitored for 21 days. Periodically, blood was collected for CBC, serum biochemical analyses, and detection of FHV-1 DNA via PCR assay. For shelter cats, a conjunctival swab specimen was collected for FHV-1 PCR assay, and blood mononuclear cells were tested via virus isolation (with or without hydrocortisone) and FHV-1 PCR assay. RESULTS All SPF cats developed clinical and clinicopathologic evidence of upper respiratory tract and ocular disease only. Via PCR assay, FHV-1 DNA was detected in blood of all SPF cats at least once between 2 and 15 days after inoculation. Feline herpesvirus type 1 DNA was detected in conjunctival swabs of 27 shelter cats; 25 had clinical signs of herpetic infection. However, virus was not isolated from mononuclear cell samples of any shelter cat regardless of passage number or whether hydrocortisone was present in the culture medium; FHV-1 DNA was not detected in any mononuclear cell sample collected from shelter cats. CONCLUSIONS AND CLINICAL RELEVANCE A brief period of viremia occurred in cats undergoing primary herpetic disease but not in cats undergoing presumed recrudescent herpetic disease. Viremia may be important in the pathogenesis of primary herpetic disease but seems unlikely to be associated with recrudescent disease.

Intracranial extension of retrobulbar blastomycosis (Blastomyces dermatitidis) in a dog

Blastomycosis (Blastomyces dermatitidis) is a fungal disease that is endemic in the southern United States. This case report illustrates the clinical, MRI and histopathologic findings in a dog with invasion of a retrobulbar blastomycotic lesion into the calvarium. A 5-year-old intact female Weimaraner was referred for a 2-month history of change in behavior and recent onset of visual deficits. Magnetic resonance imaging (MRI) examination revealed a large (5.8 × 2.0 × 2.5 cm) mass extending from the left orbit through a circular defect in the left cranioventral aspect of the calvarium caudally to the level of the pituitary fossa and interthalamic adhesion. The mass was heterogeneously iso- to hypointense on T2-W images, slightly hypointense on T1-W images, did not attenuate on fluid attenuated inversion recovery (FLAIR) images, and did not show evidence of susceptibility artifact on T2*-W gradient recalled echo (GRE) images. Vasogenic edema and associated mass effect were noted. The mass showed strong homogeneous contrast enhancement with well-defined margins and had thickening of the adjacent meninges (dural tail sign). Based on MRI findings a malignant neoplastic process was considered most likely and the patient was placed on oral prednisone to decrease peri-tumoral inflammation. The dog initially improved but was euthanized 3 weeks later for worsening clinical signs. Histopathologic assessment of the mass revealed marked pyogranulomatous optic neuritis with intralesional fungal yeasts consistent with blastomycosis (Blastomyces dermatitidis). To our knowledge this is the first report of invasion of a retrobulbar blastomycotic lesion into the calvarium in a dog.

Actinomyces endogenous endophthalmitis in a cat following multiple dental extractions

An 8-year-old, brachycephalic, mixed breed cat underwent full mouth tooth extractions for the treatment of tooth root abscessation. Subsequently, the cat developed anterior uveitis refractory to topical therapy that eventually necessitated enucleation. Actinomyces species were isolated from both the tooth root abscesses and the anterior chamber after enucleation. Histopathology of the enucleated eye revealed panophthalmitis with abundant intralesional bacteria morphologically consistent with Actinomyces. Between the time of tooth root extraction and enucleation (20 weeks), the cat was diagnosed with hyperthyroidism and treated with oral steroids for inflammatory bowel syndrome. We believe this report represents a rare case of endogenous endophthalmitis secondary to dental disease, possibly precipitated by concurrent immunosuppression.

Comparison of two bupivacaine delivery methods to control postoperative pain after enucleation in dogs

OBJECTIVE To compare the efficacy of a preoperative retrobulbar injection of bupivacaine to an intraoperative splash block of bupivacaine in controlling postoperative pain following enucleation in dogs. ANIMALS STUDIED Prospective, randomized, double-masked clinical study of 31 client owned dogs with end-stage ophthalmic disease requiring enucleation. PROCEDURES Dogs admitted for unilateral enucleation were randomly assigned to receive bupivacaine 0.5% (1 mL/kg) into the retrobulbar space either via an inferior-temporal palpebral (ITP) injection preoperatively or an intraoperative splash block. Pain was assessed prior to pre-anesthetic sedation and at 0, 0.25, 0.5, 1, 2, 4 6, 8, and 24 hours (H) after extubation by masked observers using a previously described subjective pain scoring system. Rescue analgesia was initiated if overall pain score was >9 or if the score in any category at any time point was >3. RESULTS There were no adverse reactions. One of 15 dogs that received bupivacaine via a preoperative retrobulbar ITP injection required rescue analgesia. There was no significant difference between groups with regard to the need for rescue analgesia or pain scores at any time point or overall. CONCLUSIONS AND CLINICAL RELEVANCE Pain control using an intraoperative orbital splash administration of bupivacaine is not significantly different to a preoperative retrobulbar injection of bupivacaine.

Effects of sampling instrument and processing technique on DNA yield and detection rate for feline herpesvirus-1 via polymerase chain reaction assay

OBJECTIVE To assess effects of disease severity, sampling instrument, and processing technique on extracted DNA yield and detection rate for feline herpesvirus-1 (FHV-1) via PCR assay. SAMPLE POPULATION Crandell-Rees feline kidney (CRFK) cells grown in vitro and conjunctival samples from 40 eyes of 20 cats. PROCEDURES Samples of CRFK cells (collected by use of a swab or cytology brush, with or without suspension in PBS solution) underwent DNA extraction; DNA yield was quantified spectrophotometrically. In affected cats, signs of herpetic disease were subjectively assessed. Conjunctival swab and brush samples were collected bilaterally for measurement of DNA concentration; a defined mass (DM) of DNA and defined volume (DV) of sample were assessed for FHV-1 via PCR assays. RESULTS For CRFK cells, DNA yields from unsuspended swabs and brushes were greater than for suspended swabs and brushes; suspended swab samples yielded less DNA than suspended brush samples. For conjunctival samples, DNA yields from swabs were greater than for brushes. Clinical score was not correlated with double-stranded DNA yield collected via either sampling instrument; however, cats with FHV-1-positive assay results had higher clinical scores than cats with FHV-1-negative results. Detection of FHV-1 in swab and brush samples was similar. Double-stranded DNA yield and FHV-1 detection were inversely related via DM-PCR assay. The DV-PCR assay had a significantly higher FHV-1 detection rate than the DM-PCR assay. CONCLUSIONS AND CLINICAL RELEVANCE The DV-PCR assay of DNA extracted from an unsuspended swab sample was the preferred method for assessment of conjunctival shedding of FHV-1 in cats.

In vitro evaluation of the inhibitory effect of canine serum, canine fresh frozen plasma, freeze-thaw-cycled plasma, and Solcoseryl™ on matrix metalloproteinases 2 and 9.

OBJECTIVE Compare the efficacy of canine serum, fresh frozen plasma (FFP), freeze-thaw-cycled plasma (FTCP), and Solcoseryl(™) at inhibiting matrix metalloproteinases (MMP) 2 and 9 in vitro. PROCEDURE Matrix metalloproteinases 2 and 9 activity in the presence of serum, FFP, FTCP, or Solcoseryl(™) was assayed using a commercially available fluorogenic gelatinase activity kit. RESULTS Matrix metalloproteinases 2 activity in the presence of serum, FFP, FTCP, and Solcoseryl(™) was 20.84%, 5.76%, 8.10%, and 83.03%, respectively of uninhibited MMP 2 activity. MMP 9 activity in the presence of serum, FFP, FTCP, and Solcoseryl(™) was 57.36%, 58.35%, 49.35%, and -8.69%, respectively of uninhibited MMP 9 activity. CONCLUSION Serum, FFP, and FTCP exhibit similar levels of MMP 2 and 9 inhibitions. Solcoseryl(™) causes minimal MMP 2 inhibition, but profound MMP 9 inhibition.

Visual outcome in cats with hypertensive chorioretinopathy

PURPOSE To investigate factors associated with long-term visual outcome in cats with hypertensive chorioretinopathy. ANIMALS STUDIED Eighty-eight client-owned cats diagnosed with hypertensive chorioretinopathy. PROCEDURE Medical records from cats with systemic hypertension and associated retinal lesions were reviewed. RESULTS Most cats (61%) were blind in both eyes at presentation. Presence of menace response at last follow-up evaluation was positively correlated with presence of menace response at presentation (P = .0025), time to complete retinal reattachment (P < .0001), and gender (P = .0137). Seventy-six of 132 eyes (57.6%) that were blind at presentation regained some vision following treatment. At the time of last evaluation, 101/176 eyes (60%) had a positive menace response, while 34/46 (74%) eyes with a follow-up of >6 months had a positive menace response. Eyes that had a menace response at presentation were 17 and 37 times more likely to have a menace response at last examination compared to eyes blind for less than 2 weeks and eyes blind greater than 2 weeks, respectively. Female cats were overrepresented (62.5% of cases), and male cats were 4.2 times more likely to be visual at time of last examination compared to female cats. CONCLUSIONS With treatment, the prognosis for long-term vision in cats with hypertensive chorioretinopathy, even following complete retinal detachment, is good.