Comparison of 2 sampling methods for molecular detection of bacteria or fungi from feline hair and scale specimens

Skin diseases of cats are among the most frequent client motivations for a veterinary consultation. Both carpet and toothbrush sampling are commonly used to obtain hair and scale samples for microbiologic testing. Although molecular tests have become more accessible and more widely used by clinicians, the ideal collection method for clinical specimens is unclear. To assess their performance in retrieving microbial DNA from clinical samples, we compared the bacterial and fungal DNA load in hair and skin scale samples collected using carpet or toothbrush methods. We evaluated sample DNA yield using fluorometry, spectrophotometry, and quantitative PCR. Despite no measurable differences in sample weight, toothbrush samples yielded significantly higher bacterial (p = 0.028) and fungal (p = 0.005) DNA loads compared to carpet samples, regardless of disease status. The toothbrush method was more effective in harvesting microbial DNA from hair and skin scale samples.

Local treatment for canine anal sacculitis: A retrospective study of 33 dogs

Background

Little information has been published regarding treatment of canine anal sacculitis (AS).

Objectives

Primary objective: determine the outcomes of AS local treatment at the referral dermatology service of the authors' institution. Secondary objective: determine signalment, body condition score (BCS), stool quality and comorbidities associated with AS.

Animals

Thirty‐three dogs with AS presented to the referral dermatology service between 1 January 2010 and 31 March 2021.

Materials and methods

An electronic medical record search was conducted. Information regarding sex, breed, age at disease onset, weight, BCS, stool quality, comorbidities, treatment and treatment outcome were collected. Treatment outcome was categorised as “resolved clinically”, “clinical signs resolved per owner”, “did not complete treatment” or “failed”. Dogs were excluded if seen by another service, not treated for AS, or if perianal sinuses (fistulae), anal sac masses, or anal sac abscesses were identified.

Results

Nineteen dogs were male and 14 female. Twenty‐four breeds were included. Average age at disease onset was 4.4 years. Average BCS was 5.8 of 9. Stool quality was “poor” in seven of 33 and normal in 23 of 33 cases. Atopic dermatitis was the most common comorbidity (12 of 33). Treatment typically consisted of anal sac flushing with saline followed by infusion using a commercially available steroid/antibiotic/antifungal ointment. Treatment was repeated on average 2.9 times. Resolution of AS was obtained in 24 of 33 cases, clinical signs resolved per owner in four of 33, five of 33 cases did not complete treatment, and no cases failed treatment.

Conclusions and clinical relevance

Local treatment with flushing and infusion is effective for treating AS in dogs.

Background – Little information has been published regarding treatment of canine anal sacculitis (AS).

Objectives – Primary objective: determine the outcomes of AS local treatment at the referral dermatology service of the authors' institution. Secondary objective: determine signalment, body condition score, stool quality and comorbidities associated with AS.

Conclusions and clinical relevance – Local treatment with flushing and infusion is effective for treating AS in dogs.

Pathology in Practice

In collaboration with the American College of Veterinary Pathologists.

Validation of the 0-10 verbal numeric scale for assessment of pruritus severity in dogs

BACKGROUND

The pruritus Visual Analog Scale (pVAS) is currently the only validated tool for assessing canine pruritus. A verbal numeric scale (VNS) offers an alternative if clients are not present or able to complete the pVAS.

HYPOTHESIS/OBJECTIVE

To validate the 0-10 VNS and evaluate its interchangeability with the pVAS.

ANIMALS

251 dogs were included in the study.

MATERIALS AND METHODS

Dog owners were asked to assess their pet's pruritus level using the pVAS, the 0-10 VNS and the verbal rating categories (mild, moderate, severe) in one or two subsequent visits. To be valid, VNS must satisfy the following: correlate with pVAS (criterion validity); indicate reduction in itch score after an antipruritic intervention (construct validity); and have scores related to the verbal rating categories that are significantly different (content validity). VNS and pVAS interchangeability and the percentage of clients that preferred the VNS and pVAS also were evaluated.

RESULTS

The VNS and pVAS correlation for visits 1 and 2 was good (r_ICC  = 0.9) and excellent (r_ICC  = 0.94). The VNS scores were significantly decreased after antipruritic interventions (P < 0.001). The VNS scores associated with the verbal rating scale categories (mild, moderate and severe) were significantly different (P < 0.001). The 95% limits of agreement for the pVAS and VAS were outside the limit of acceptability of ±2 (-2.0, 2.57). Most clients (69%) preferred the pVAS to the VNS.

CONCLUSIONS AND CLINICAL RELEVANCE

The VNS is a valid scale to evaluate canine pruritus; however, the VNS and pVAS are not interchangeable.

Patulous Eustachian tube and palatine defect in a Dachshund with chronic unilateral otitis externa and otitis media

BACKGROUND

Patulous Eustachian tube (pET) is a rare dysfunction of the Eustachian tube described in humans. It is characterized by failure of the ET to close, resulting in unrestricted passage of air, sound and material between the nasopharynx and the middle ear.

OBJECTIVE

To report a case of pET associated with otitis in a dog.

ANIMAL

A 6-year old-female spayed Dachshund dog.

METHODS AND MATERIALS

Otoscopic examination, cytological evaluation, culture and susceptibility, computerized tomography (CT), video-otoscopic flushing and surgery.

RESULTS

Left ear otoscopic examination revealed erythema, purulent frothy discharge, ceruminous gland hyperplasia, stenosis and a partial tear of the tympanum. Cytological evaluation from the left external canal showed neutrophils, macrophages, rods and cocci. Aerobic culture showed predominantly multidrug-resistant Pseudomonas aeruginosa. The CT findings of the left ear included chronic changes in the external canal, marked lysis of the tympanic bulla and marked dilation of the ET. During video-otoscope flushing, saline drained through the mouth. Bilateral incomplete hypoplasia of the soft palate was noted. Total ear canal ablation and bulla osteotomy with ET dissection were curative. Histopathological findings were compatible with chronic otitis externa (OE) and media.

CONCLUSION AND CLINICAL IMPORTANCE

To the best of the authors' knowledge, this is the first case of pET described in animals. The ET dysfunction and palatine defect were likely the cause of the otitis in this dog. Clinicians should investigate pET in animals with signs of OE characterized by frothy liquid and food fragments in the ear canal in addition to sneezing after drinking water.

Dermal arteritis of the nasal philtrum: a retrospective study of 23 dogs

BACKGROUND

Dermal arteritis of the nasal philtrum (DANP) is a cutaneous vascular condition that selectively targets large vessels of the nasal philtrum of dogs; little information is published about this disease.

OBJECTIVE

The aim of this study was to report the signalment, clinical signs, treatment options and outcome of dogs with DANP, and to propose a rationale for the clinical diagnosis.

ANIMALS

Twenty-three dogs from four referral veterinary clinics from January 2002 to July 2018.

METHODS AND MATERIALS

Retrospective analysis of medical records of dogs with diagnosis of DANP.

RESULTS

The mean age at disease onset was 5.3 years. Nineteen dogs were pure-bred (11 different breeds) and four were mixed breed. Twenty-three dogs had a clinical diagnosis of DANP and three of these had histopathological confirmation. Eight dogs had episodes of profuse arterial bleeding from the lesion, nine had minor bleeding and six no bleeding. Twenty dogs were managed medically with monotherapy or combined therapy of topical tacrolimus, prednisolone, doxycycline and niacinamide, and/or pentoxifylline. Long-term tacrolimus was prescribed for 15 cases, eight of those cases as sole therapy. Treatment was declined for three dogs and four dogs were lost to follow-up. The lesion was satisfactorily controlled in 12 dogs and well-controlled in four dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

The distinctive presentation of DANP substantiates the clinical diagnosis. Medical treatment seems to be effective in controlling DANP and tacrolimus used as sole or adjunctive therapy appears to manage the disease satisfactorily.

Canine Pruritus Visual Analog Scale: how does it capture owners' perception of their pet's itching level?

BACKGROUND

Accurate measurement of pruritus severity is difficult in veterinary medicine.

OBJECTIVES

To determine how the changes in Pruritus Visual Analog Scale (PVAS) scores at follow-up visits agree with the owners' perceptions of improvement of their pet's pruritus.

ANIMALS

One hundred and ninety two pruritic dogs were included in the prospective study and 196 in the retrospective study.

METHODS AND MATERIALS

Owners were randomly assigned into five groups and PVAS scores were recorded during two consecutive visits. Group A: previous scores were shown before completing the PVAS; Group B: PVAS was completed then owners were shown previous scores and asked to repeat the PVAS; Group C: PVAS was completed as reported previously; Group D: PVAS and a 0-10 verbal scale (VS) were completed. Retrospectively, PVAS scores were analysed during at least three consecutive visits. The average percentage and kappa agreements were calculated for all groups. In addition, PVAS and VS scores were compared in Group D.

RESULTS

The average percentage and kappa agreements were higher in groups A (96%; 0.81), B [before (80%; 0.54), after (82%; 0.59) previous score] and D (85%; 0.47). Group C (79%; 0.37) had the lowest agreement. PVAS and VS scores were not significantly different (P = 0.56) in Group D. The average percentage and kappa agreements for the retrospective study were 50.8% and 0.25. The highest values (63%; 0.355) were noted at 30-60 day visit intervals.

CONCLUSIONS AND CLINICAL IMPORTANCE

Showing owners previous scores could improve how PVAS captures the owner's perception of their dog's itching level.

Salivary proteomics of healthy dogs: An in depth catalog

Objective

To provide an in-depth catalog of the salivary proteome and endogenous peptidome of healthy dogs, evaluate proteins and peptides with antimicrobial properties, and compare the most common salivary proteins and peptides between different breed phylogeny groups.

Methods

36 healthy dogs without evidence of periodontal disease representing four breed phylogeny groups, based upon single nucleotide polymorphism haplotypes (ancient, herding/sighthound, and two miscellaneous groups). Saliva collected from dogs was pooled by phylogeny group and analyzed using nanoscale liquid chromatography-tandem mass spectrometry. Resulting tandem mass spectra were compared to databases for identification of endogenous peptides and inferred proteins.

Results

2,491 proteins and endogenous peptides were found in the saliva of healthy dogs with no periodontal disease. All dog phylogeny groups’ saliva was rich in proteins and peptides with antimicrobial functions. The ancient breeds group was distinct in that it contained unique proteins and was missing many proteins and peptides present in the other groups.

Conclusions and clinical relevance

Using a sophisticated nanoscale liquid chromatography-tandem mass spectrometry, we were able to identify 10-fold more salivary proteins than previously reported in dogs. Seven of the top 10 most abundant proteins or peptides serve immune functions and many more with various antimicrobial mechanisms were found. This is the most comprehensive analysis of healthy canine saliva to date, and will provide the groundwork for future studies analyzing salivary proteins and endogenous peptides in disease states.

Evaluation of intraepidermal nerve fibres in the skin of normal and atopic dogs

BACKGROUND

Interest in intraepidermal nerve fibres (IENFs) is rising in human medicine, because variations in fibre density occur in some diseases and these neurites might contribute to disease pathogenesis. An increase in IENF density is seen in human atopic dermatitis (AD); there are no such data in atopic dogs.

OBJECTIVES

To compare the prevalence of IENFs in normal and atopic canine skin.

METHODS

Eight millimetre skin punch biopsies were taken from six sites of 25 healthy dogs without dermatitis and compared to lesional and nonlesional skin samples of dogs with AD (23 and 14 dogs, respectively). Thirty micrometre-thick paraffin-embedded sections were stained by indirect immunofluorescence for neuronal beta-3 tubulin. Only sections with detectable dermal nerves were then screened for the presence of IENFs.

RESULTS

IENFs were identified in all 25 normal nasal planum sections, but in only one biopsy collected from each of the normal canine haired skin (NCHS) sites. As there was no significant difference in IENF prevalence between NCHS areas, they were grouped together. The rate of detection of IENFs was significantly higher (one-tailed Fisher's test, P = 0.004) in lesional AD specimens (18 of 23; 78%) than in nonlesional AD (four of 14; 29%) and NCHS specimens (four of 111; 4%, P < 0.0001). The prevalence of IENF detection in nonlesional AD samples was significantly higher than in normal canine skin (P = 0.006).

CONCLUSIONS AND CLINICAL IMPORTANCE

IENFs are detected more commonly in canine AD than in normal haired skin; these results are comparable to those seen for human AD.

Can immunosuppressive therapy facilitate the diagnosis and affect the clinical signs of canine scabies? A retrospective study of 79 cases

BACKGROUND

Scabies infestation is one of the most pruritic dermatoses of dogs. It is often misdiagnosed and dogs are treated with immunomodulatory drugs (IMD) to relieve pruritus.

HYPOTHESIS/OBJECTIVES

The primary goals of this study were to determine the impact of IMD on skin scraping results, pruritus level and extent of skin lesions, and to evaluate whether disease duration is associated with positive skin scrapings and contagion.

ANIMALS

Seventy nine dogs with a final diagnosis of scabies.

METHODS

Inclusion in this retrospective study required a positive skin scraping for scabies or a clinical response to an acaricidal treatment trial.

RESULTS

The average pruritus score of dogs that received IMD (8.71) was significantly higher than those that did not (7.43; P = 0.03). However, there were no significant differences in either the rates of positive skin scrapings (79.6% versus 59.1%; P = 0.13) or the mean number of body sites affected (3.8 versus 3.4; P = 0.30) between dogs that received IMD and those that did not. Neither skin scraping status nor duration of clinical signs were correlated with a report of contagion within the household.

CONCLUSION/CLINICAL IMPORTANCE

IMD was associated with a significant increase in the pruritus level, but not with the mean number of lesional body sites. Dogs exposed to IMD had a 20.5% higher rate of positive skin scrapings. This difference could be clinically relevant and lack of statistical significance may indicate an underpowered study.

Breed-specific reference intervals for assessing thyroid function in seven dog breeds

Thyroxine (T4), free T4 (FT4), and thyrotropin (TSH) concentrations were measured in serum from 693 healthy representatives from 7 dog breeds (Alaskan Malamute, Collie, English Setter, Golden Retriever, Keeshond, Samoyed, or Siberian Husky) to determine whether breed-specific reference intervals (RIs) are warranted. Veterinarians reviewed the health history, performed a physical examination, and approved laboratory data for the enrolled dogs. Many purebred dogs had T4 and FT4 concentrations that were at, or below, the lower limits previously determined for non–breed-specific RIs. Mean concentrations of T4, FT4, and TSH varied significantly among breeds. The range of mean concentration of T4 (19.7 nmol/L [1.53 µg/dL] in English Setters to 29.0 nmol/L [2.25 µg/dL] in Keeshonds) and FT4 (12.6 pmol/L [0.98 ng/dL] in English Setters to 20.2 pmol/L [1.57 ng/dL] in Samoyeds) was considerable. Median TSH values ranged from 6.10 mIU/L (0.07 ng/mL; Alaskan Malamute and Golden Retriever) to 17.6 mIU/L (0.26 ng/mL; Collie). Mean T4 and FT4 concentrations were higher in females. Increasing age was associated with decreasing T4 and FT4, and increasing TSH concentration. The substantial ranges across breeds of measures of central tendency (mean, median) for all hormones indicate that breed-specific RIs are warranted. RIs encompassing the central 95% of reference values for all breeds combined, and for individual breeds, were calculated using nonparametric (TSH) and robust (T4, FT4) methods. Use of breed-specific RIs in combination with careful attention to the potential for pre-analytical and analytical variability in test results will improve thyroid function assessment in these breeds.

Frequency of urinary tract infection in dogs with inflammatory skin disorders treated with ciclosporin alone or in combination with glucocorticoid therapy: a retrospective study

BACKGROUND

Few studies have investigated the frequency of urinary tract infection (UTI) in dogs receiving long-term ciclosporin therapy.

HYPOTHESIS/OBJECTIVES

The goal of the study was to investigate the frequency of UTI in dogs receiving ciclosporin with or without glucocorticoids. A secondary goal was to determine whether bacteriuria, pyuria and urine specific gravity were good predictors of UTI, and if ciclosporin dose, concurrent ketoconazole therapy, sex or duration of therapy affected the frequency of UTI. Animals -  Eighty-seven dogs with various inflammatory skin disorders and 59 control dogs with inflammatory skin conditions that had not received glucocorticoids or ciclosporin for 6 months were enrolled.

METHODS

This study was retrospective. The first urine culture from dogs receiving ciclosporin was compared with control dogs using Fisher's exact test. A logistic mixed model was used to test for association between a positive bacterial culture and duration of treatment, dose of ciclosporin, concurrent ketoconazole therapy and sex. The sensitivities and specificities for bacteriuria, pyuria and urine specific gravity were determined.

RESULTS

Twenty-six of 87 (30%) ciclosporin-treated dogs had at least one positive culture. Compared with 3% positive control samples, 15% were positive in treated dogs (P=0.027). The sensitivity and specificity were, respectively, 64.1 and 98.1% for bacteriuria, 74.4 and 70.9% for pyuria, and 56.4 and 65.3% for urine specific gravity. All other analysed parameters were not significantly different.

CONCLUSIONS AND CLINICAL IMPORTANCE

The results suggest that routine urine cultures and assessment of bacteriuria by cystocentesis should be part of the monitoring for dogs on long-term ciclosporin with and without glucocorticoids.

The expression of histamine H4 receptor mRNA in the skin and other tissues of normal dogs

The histamine 4 (H(4)) receptor was first cloned and characterized in 2000 using the human H(3) receptor DNA sequence. The H(4) receptor has been shown to participate in various aspects of inflammation, such as chemotaxis, upregulation of adhesion molecule expression and modulation of cytokine secretion. The primary goal of this study was to determine whether H(4) receptor mRNA is expressed in normal canine skin by performing an RT-PCR. An additional goal was to determine the expression of this receptor in the colon, liver, spleen and kidney. Tissues were collected from five healthy, young-adult pit bull dogs. Samples were immediately placed in RNAlater(®) solution and stored at -20°C until processed. The amplified products in all skin samples in addition to the colon, liver, spleen and kidney (variable expression) had the expected size of 400-500 bp. The sequenced amplicons matched the National Center for Biotechnology Information published sequence for the canine H(4) receptor. The study results showed that canine normal skin expresses the H(4) receptor mRNA. Further studies using immunohistochemistry should be conducted to demonstrate the expression of the H(4) receptor at the protein level and to localize the expression of this receptor in the skin.

The efficacy of imiquimod 5% cream (Aldara® in the treatment of aural plaque in horses: a pilot open-label clinical trial

Aural plaques affect at least 22% of horses and can be asymptomatic or cause ear sensitivity. Immunohistochemical and electron microscopy studies have shown a strong association between aural plaques and papilloma virus. The purpose of this study was to investigate the efficacy of imiquimod 5% cream, an immune response modifier with potent antiviral activity, in the treatment of equine aural plaques. Twenty-one horses were enrolled and 16 completed the study. Imiquimod 5% cream was applied three times a week, every other week. When both ears were affected only the worst affected ear was treated. Adverse effects in all horses included marked local inflammation, exudation and thick crust formation at the site of treatment and the adjacent skin. Removal of the crust before treatment was painful and required sedation in most horses. Complete resolution of lesions was noted in all horses immediately post-treatment and the long-term resolution rate was 87.5%. Duration of therapy ranged from 1.5 to 8 months (median: 2.9 mean: 3.5). All horses were followed-up for 12-22 months after treatment was discontinued and only two horses had a recurrence of lesions. Clinical signs related to the aural plaques prior to treatment were reported in 11 of 16 (68.8%) horses and included resistance to touching the ears and bridling. Complete resolution of these signs was reported by the owners in all of the horses followed-up for at least 12 months. In conclusion, the topical application of imiquimod 5% cream is an efficacious treatment for aural plaques in horses.

Characterization and quantification of ceramides in the nonlesional skin of canine patients with atopic dermatitis compared with controls

As in humans, there is mounting evidence in support of an abnormal skin barrier contributing to the pathogenesis of canine atopic dermatitis (AD). Studies in people with AD have associated an abnormal skin barrier with deficiencies in ceramides, which represent important components of the stratum corneum (SC) intercellular lipid lamellae. Therefore, the goal of this study was to determine if the SC of dogs with AD is deficient in ceramides compared to normal dogs. Samples of SC were obtained from nonlesional skin of the caudal abdomen of 14 patients with AD and 14 age-, breed- and sex-matched healthy controls using a cyanoacrylate stripping procedure, and the subclass and relative amount of ceramides were assessed blindly by thin layer chromatography. Paired t-tests using R statistical computer software revealed the percentage amounts of ceramides 1 and 9 were significantly lower in nonlesional skin of AD dogs compared to controls (P= 0.034 and P= 0.047, respectively), and the cholesterol percentage amount was significantly higher in AD dogs than in controls (P= 0.016). Furthermore, the cholesterol/ceramide ratio was significantly higher in the AD group with respect to controls (P= 0.014). These findings suggest that decreased amounts of ceramides in the skin of dogs with AD may be involved in the impaired barrier function of their skin.

Effects of a single injection of methylprednisolone acetate on serum biochemical parameters in 11 cats

BACKGROUND

Therapeutic use of corticosteroids has been implicated in a variety of serum biochemical abnormalities in dogs; however, the effects in cats are less well characterized.

OBJECTIVE

The objective of this brief communication is to report serum biochemical changes in response to methylprednisolone acetate (MPA) in adult cats.

METHODS

Serum biochemical profiles were performed on 11 cats with dermatologic diseases at baseline, 3-6 days, and 16-24 days after a single intramuscular dose of 5 mg/kg MPA.

RESULTS

Median serum albumin and bicarbonate concentrations and amylase activity were increased compared to baseline at both post-treatment time points; aspartate aminotransferase activity and magnesium concentration were increased at 3-6 days post-treatment only; and alkaline phosphatase activity and total calcium concentration were increased at 16-24 days post-treatment only. Median serum creatinine concentration was decreased compared to baseline at both post-treatment time points. Examination of data from individual cats revealed significant variability in serum biochemical changes in response to MPA. No adverse clinical reactions to the drug were reported.

CONCLUSIONS

A single dose of MPA results in significant changes in some serum biochemical values in cats, although individual responses will vary.

Efficacy of imiquimod 5% cream in the treatment of equine sarcoids: a pilot study

Imiquimod is an immune response modifier with potent antiviral and antitumour activity. The objective of this pilot study was to evaluate the efficacy of an imiquimod 5% cream (Aldaratrade mark: 3M, Saint Paul, MN, USA) as a topical treatment for equine sarcoids. Fifteen horses with a total of 19 tumours were enrolled, including mixed (7), fibroblastic (5), flat (3), verrucous (2), and nodular (2) types. Baseline data included history, physical examination, tumour location, measurement and digital photography. Imiquimod was applied by the owners three times a week until complete resolution of the tumour or 32 weeks, whichever occurred first. Tumours were measured and photographed every 4 weeks. Treatment efficacy was defined as 75% or greater reduction of tumour size by the end of the trial. Four sarcoids were withdrawn from the study. Twelve of the remaining 15 tumours (80%) showed more than 75% reduction in size and nine (60%) totally resolved between 8 and 32 weeks. The most common adverse effects of exudation, erythema, erosions, depigmentation and alopecia were limited to the tumour and adjacent areas. The results suggest that topical imiquimod is a therapeutic option for the treatment of equine sarcoids, although more detailed studies are required to corroborate these initial findings.

Hemodynamic effects of methylprednisolone acetate administration in cats

OBJECTIVE

To investigate the mechanisms by which corticosteroid administration may predispose cats to congestive heart failure (CHF).

ANIMALS

12 cats receiving methylprednisolone acetate (MPA) for the treatment of dermatologic disorders.

PROCEDURE

The study was conducted as a repeated-measures design. Various baseline variables were measured, after which MPA (5 mg/kg, IM) was administered. The same variables were then measured at 3 to 6 days and at 16 to 24 days after MPA administration. Evaluations included physical examination, systolic blood pressure measurement, hematologic analysis, serum biochemical analysis, thoracic radiography, echocardiography, and total body water and plasma volume determination.

RESULTS

MPA resulted in a substantial increase in serum glucose concentration at 3 to 6 days after administration. Concurrently, RBC count, Hct, and hemoglobin concentration as well as serum concentrations of the major extracellular electrolytes, sodium and chloride, decreased. Plasma volume increased by 13.4% (> 40% in 3 cats), whereas total body water and body weight slightly decreased. All variables returned to baseline by 16 to 24 days after MPA administration.

CONCLUSIONS AND CLINICAL RELEVANCE

These data suggest that MPA administration in cats causes plasma volume expansion as a result of an intra to extracellular fluid shift secondary to glucocorticoid-mediated extracellular hyperglycemia. This mechanism is analogous to the plasma volume expansion that accompanies uncontrolled diabetes mellitus in humans. Any cardiovascular disorders that impair the normal compensatory mechanisms for increased plasma volume may predispose cats to CHF following MPA administration.

The impact of body site, topical melatonin and brushing on hair regrowth after clipping normal Siberian Husky dogs

The aims of this study were to determine the impact of body site, vigorous brushing and topical melatonin treatment on hair regrowth after clipping normal dogs. Siberian Husky dogs were randomly assigned to three groups of eight dogs each. All dogs had the lumbosacral region and both lateral thighs clipped. The left thigh and lumbosacral area received no treatment and were compared in all 24 dogs. Eight dogs had the right thigh treated with 0.1% melatonin twice daily for 2 months, and hair regrowth was compared with the left thigh. Eight dogs had the right thigh brushed twice daily for 2 months, and hair regrowth was compared with the left thigh. Eight dogs had neither thigh treated. Hairs were plucked before and 2 months postclipping, and the proportion of hair growth from the original length was calculated and compared as described above. Biopsy samples were collected before and after treatment to determine if brushing induced dermal inflammation and melatonin increased the proportion of anagen follicles. Proportionally, left thigh hairs were significantly longer compared to lumbosacral hairs 2 months postclipping. No significant differences in hair regrowth were noted between the nontreated thigh and the thigh treated with melatonin or brushed. No significant difference in dermal inflammation was noted before and after brushing. No significant differences were observed in the proportion of anagen follicles before and after topical melatonin treatment. Our results showed that the hairs in the lumbosacral region were proportionally shorter than lateral thigh hairs 2 months postclipping. Moreover, topical melatonin and brushing had no impact on hair regrowth after clipping normal dogs.

Frequency of urinary tract infection among dogs with pruritic disorders receiving long-term glucocorticoid treatment

OBJECTIVE

To determine frequency of urinary tract infection (UTI) among dogs with pruritic disorders that were or were not receiving long-term glucocorticoid treatment.

DESIGN

Observational study.

ANIMALS

127 dogs receiving glucocorticoids for > 6 months and 94 dogs not receiving glucocorticoids.

PROCEDURE

Bacterial culture of urine samples was performed in dogs receiving long-term glucocorticoid treatment, and information was collected on drug administered, dosage, frequency of administration, duration of glucocorticoid treatment, and clinical signs of UTI. For dogs not receiving glucocorticoids, a single urine sample was submitted for bacterial culture.

RESULTS

Multiple (2 to 6) urine samples were submitted for 70 of the 127 (55%) dogs receiving glucocorticoids; thus, 240 urine samples were analyzed. For 23 of the 127 (18.1%) dogs, results of bacterial culture were positive at least once, but none of the dogs had clinical signs of UTI. Pyuria and bacteriuria (present vs absent) were found to correctly predict results of bacterial culture for 89.9% and 95.8% of the samples, respectively. Type of glycocorticoid, dosage, frequency of administration, and duration of treatment were not associated with frequency of UTI. None of the urine samples from dogs not receiving glucocorticoids yielded bacterial growth. The frequency of UTI was significantly higher for dogs treated with glucocorticoids than for dogs that had not received glucocorticoids.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that dogs receiving long-term glucocorticoid treatment have an increased risk of developing a UTI. On this basis, we recommend that urine samples be submitted for bacterial culture at least yearly for such dogs.

The effect of body region on the canine hair cycle as defined by unit area trichogram

The impact of anatomic location on trichogram analysis of the hair cycle phases was evaluated in 15 clinically normal dogs. The purposes of this study were to determine if the number of hairs in anagen and telogen vary among anatomic sites within a dog and to see whether there is an optimal region to sample hairs for canine trichogram evaluation of the hair cycle phases. In each dog eight sites were sampled. Four (26.7%) of the 15 dogs had no significant differences in the number of hairs in anagen and telogen among the eight body sites examined. Nine (81.8%) of the remaining 11 dogs had only one site that revealed significant differences in the number of hairs in anagen or telogen. In seven (77.8%) of these dogs only the anagen differed significantly, and in two (22.2%) dogs both phases differed significantly. Two (18.2%) dogs revealed two sites with significant differences in the number of hairs in anagen. The number of hairs in anagen and telogen in the shoulder area did not vary significantly in any of the dogs. This observation, coupled with the ease of sampling at this site, indicates that the shoulder is the site of choice when studying variations in ratios of hair cycle phases using unit area trichogram. Our results also suggest that numbers of telogen and anagen hairs from body regions with different hair shaft lengths do not vary significantly, and the occasional inconsistent results noted at some body sites might be due to sample collection technique.

An analysis of canine hair re-growth after clipping for a surgical procedure

Hair growth and replacement have been studied extensively in humans, sheep and laboratory rodents, but in dogs and other mammalian species few studies have been published. The objectives of this study were: (1) to determine the time required for the hair to re-grow in dogs after clipping for a surgical procedure; (2) to define whether the season of the year influenced the period of time required for re-growth and; (3) to determine if season might influence the telogen: anagen ratio. Eleven Labrador retrievers were recruited during spring, 10 during summer, six during autumn and 10 during winter. Hairs re-grew to their preclipped length in 14.6 weeks, 14.5 weeks, 13.6 weeks and 15.4 weeks when shaved in the spring, summer, autumn and winter, respectively. The differences in these values were not significant suggesting that season has no effect on the rate of hair re-growth in Labrador retrievers housed indoors (P = 0.12). The mean values for the telogen: anagen ratio in each season were: 5.2 (spring), 6.1 (summer), 9.5 (autumn), and 5.3 (winter). The differences in these values also were not significant (P = 0.89). The percentage of hairs in telogen was over 80% in all four seasons.

Effects of propofol-induced sedation on intradermal test reactions in dogs with atopic dermatitis

We compared the effect of propofol and saline control on intradermal test reactions in dogs with atopic dermatitis undergoing outpatient intradermal testing (IDT). Nineteen dogs were used in this clinical study. Patients were randomly allocated to receive either intravenous (IV) propofol or IV 0.9% saline, and IDT was performed on the right or left (randomized) lateral thorax. One investigator, unaware of the treatments, interpreted all IDT results. Injection sites were analysed using a subjective and objective method. A value of P <or= 0.05 was considered significant. When all injection sites were subjectively analysed for reactions >or= 1+ on all dogs, significantly more positive sites were apparent during propofol sedation than during saline administration. In addition, the greater number of individual dogs experiencing more positive reactions >or= 1+ during propofol sedation was significant. When subjectively analysing reactions >or= 2+, the greater number of positive reactions and the greater number of dogs with more positive reactions observed during propofol treatment was not significantly different from the saline control. When analysed objectively, the greater number of positive reactions observed during propofol sedation was not significant. A greater number of dogs had higher subjective scores and larger objective measurements during propofol sedation compared with saline administration. In summary, propofol sedation was associated with an overall greater number of positive IDT reactions compared with the saline control. Although not always significant, this difference should be considered when choosing propofol for skin testing dogs with atopic dermatitis.

Comparison of colloid, thyroid follicular epithelium, and thyroid hormone concentrations in healthy and severely sick dogs

OBJECTIVES

To compare serum concentrations of total thyroxine (TT4), free thyroxine (fT4), and thyroid-stimulating hormone (TSH), as well as measures of thyroid follicular colloid and epithelium, between groups of healthy dogs and severely sick dogs.

DESIGN

Cross-sectional study.

ANIMALS

61 healthy dogs and 66 severely sick dogs.

PROCEDURE

Serum samples were obtained before euthanasia, and both thyroid lobes were removed immediately after euthanasia. Morphometric analyses were performed on each lobe, and serum TT4, fT4, and TSH concentrations were measured.

RESULTS

In the sick group, serum TT4 and fT4 concentrations were less than reference range values in 39 (59%) and 21 (32%) dogs, respectively; only 5 (8%) dogs had high TSH concentrations. Mean serum TT4 and fT4 concentrations were significantly lower in the sick group, compared with the healthy group. In the healthy group, a significant negative correlation was found between volume percentage of colloid and TT4 or fT4 concentrations, and a significant positive correlation was found between volume percentage of follicular epithelium and TT4 or fT4 concentrations. A significant negative correlation was observed between volume percentages of colloid and follicular epithelium in both groups.

CONCLUSIONS AND CLINICAL RELEVANCE

TT4 and fT4 concentrations are frequently less than reference range values in severely sick dogs. Therefore, thyroid status should not be evaluated during severe illness. The absence of any significant differences in mean volume percentages of follicular epithelium between healthy and severely sick dogs suggests that these 2 groups had similar potential for synthesizing and secreting thyroid hormones.

Dermal arteritis of the nasal philtrum in a Giant Schnauzer and three Saint Bernard dogs

Arteritis of the nasal philtrum is described in four dogs. Two of the Saint Bernards were related. The lesions were solitary, well-circumscribed, linear ulcers that were neither pruritic nor painful. The age of the dogs at the time the owners first noticed the lesion ranged from 3 to 6 years. The ulcers had been present for 0.5-5 years before diagnosis was pursued. Three of the dogs experienced repeated, mild episodes of arterial bleeding from the ulcers. Two dogs also experienced a severe episode of bleeding that required surgical intervention. Histopathological findings included a V-shaped ulcer, neutrophilic dermal inflammation subjacent to the ulcer and lymphoplasmacytic dermatitis bordering the ulcer. The most remarkable pathological findings were present in the deep dermal arteries and arterioles subjacent to the ulcer. The changes were characterized by subendothelial spindle cell proliferation with marked extracellular matrix deposition that stained blue with Alcian Blue (mucin) and Masson's trichrome (collagen) and resulted in intimal thickening, and stenosis of dermal arteries and arterioles. Immunohistochemical studies suggested that the proliferating spindle cells were of either myofibroblast or smooth muscle origin (actin and vimentin positive). Anti-inflammatory therapy (glucocorticoids; tetracycline and niacinamide; fish oil) may be beneficial for long-term control of this condition, however, long-term maintenance treatment appears to be necessary.