Characteristics of canine nasal discharge related to intranasal diseases: a retrospective study of 105 cases

Comparison of culture-dependent and -independent bacterial detection results on nasal swabs in dogs with nasal discharge

OBJECTIVES

The role of bacterial communities in the pathophysiology of canine nasal disease is still unclear. How and when to treat dogs with suspected secondary bacterial rhinitis and on which test to rely before making a decision to treat with antimicrobials has not been established. The objective is to compare the results of bacterial identification using agar-plate cultures and 16S rRNA gene amplicon sequencing in dogs with nasal discharge suspected to be of bacterial origin.

MATERIALS AND METHODS

Twenty-nine client-owned dogs presented for investigation of nasal disease were included in the study. Paired swabs were collected from the same affected nasal cavity. One swab was streaked on 4 agar media (Columbia Blood Agar, MacConkey, Chapman and Edward's). The other swab was stored in a sterile cryotube at -80°. Extracted DNA underwent a polymerase chain reaction targeting the V1-V3 region of the 16S rRNA gene.

RESULTS

At least one of the species detected by amplicon sequencing with a relative abundance of >10% was also identified by culture in 14 cases (48.3%), in association with marked predominance of one taxon (>80% relative abundance) in six of 14 cases. In 12 dogs (41.4%), the cultured isolates were rare or undetected components of the corresponding sequence libraries. A negative culture in the face of bacterial predominance (>50% relative abundance) of a potentially pathogenic bacteria detected by sequencing occurred in 17% (n=5) of cases; however, the use of other agar media may have decreased this percentage.

CLINICAL SIGNIFICANCE

Standard culture does not reliably predict the bacterial profile detected by 16S rRNA gene amplicon sequencing.

Construction of diagnostic prediction model for canine nasal diseases using less invasive examinations without anesthesia

Advanced imaging techniques under general anesthesia are frequently employed to achieve a definitive diagnosis of canine nasal diseases. However, these examinations may not be performed immediately in all cases. This study aimed to construct prediction models for canine nasal diseases using less-invasive examinations such as clinical signs and radiography. Dogs diagnosed with nasal disease between 2010 and 2020 were retrospectively investigated to construct a prediction model (Group M; GM), and dogs diagnosed between 2020 and 2021 were prospectively investigated to validate the efficacy (Group V; GV). Prediction models were created using two methods: manual (Model 1) and LASSO logistic regression analysis (Model 2). In total, 103 and 86 dogs were included in GM and GV, respectively. In Model 1, the sensitivity and specificity of neoplasia (NP) and sino-nasal aspergillosis (SNA) were 0.88 and 0.81 in GM and 0.92 and 0.78 in GV, respectively. Those of non-infectious rhinitis (NIR) and rhinitis secondary to dental disease (DD) were 0.78 and 0.88 in GM and 0.64 and 0.80 in GV, respectively. In Model 2, the sensitivity and specificity of NP and SNA were 0.93 and 1 in GM and 0.93 and 0.75 in GV, respectively. Those of NIR and DD were 0.96 and 0.89 in GM and 0.80 and 0.79 in GV, respectively. This study suggest that it is possible to create a prediction model using less-invasive examinations. Utilizing these predictive models may lead to appropriate general anesthesia examinations and treatment referrals.

Noninvasive Thermographic Photographing as an Assessment of the State of Discomfort in a Dog Receiving Radiation Therapy

Simple Summary

In humans, radiation induces dilation of the capillaries and inflammatory reactions, which raise skin temperature; and thermography is used to detect abnormalities after radiation therapy. However, in the field of veterinary nursing, there are no reports objectively evaluating the condition of dogs after radiation therapy using thermography. Therefore, we aimed to investigate the nasal irradiation temperature, behavioral changes, and post-irradiation pain scores in a dog receiving radiation therapy for intranasal tumors. There were no differences in behavior before and after irradiation, and pain scores were low, but the nasal planum temperature increased significantly after irradiation. Since there are individual differences in stress-related behaviors, such as pain and discomfort, assessing a dog’s pain using only subjective assessment methods, such as appearance and behavioral evaluation, is limited. In this study, we used thermography to understand changes in conditions that could not be detected by routine monitoring alone. This method is non-invasive, objective, and indispensable for proposing appropriate care.

Abstract

In humans, radiation induces dilation of capillaries and inflammatory reactions to raise skin temperature. Thermography is used to detect abnormalities after radiation therapy (RT). However, in veterinary nursing, objective evaluation of the condition of dogs after RT using thermography has not been reported. We investigated the nasal irradiation temperature, behavioral changes, and post-irradiation pain scores in a dog receiving RT for intranasal tumors. The temperature of the nasal planum gradually increased after irradiation, reaching a significantly higher value at 120–240 min. The highest temperature was 42.3 °C and the average temperature increased by 4.4 °C. Behavioral analysis pre- and post-RT did not vary significantly. Post-RT pain levels evaluated by the pain scale ranged from 0 to 1 throughout. No veterinary treatment was provided. In humans, increased skin temperature after radiation causes psychological stress, i.e., pain and discomfort, but no such behavioral changes were observed in this case. Given individual differences in stress-related behaviors, such as pain and discomfort, assessing a dog’s painfulness using only subjective methods, such as appearance and behavioral evaluation, is limited. We used thermography to assess changes in conditions not detectable by routine monitoring alone. This method is non-invasive, objective, and indispensable for providing appropriate care.

Nasal foreign bodies identified by rhinoscopy in dogs: 42 cases

OBJECTIVE

To evaluate signalment, clinical presentation, location and type of nasal foreign bodies identified by rhinoscopy in dogs.

MATERIALS AND METHODS

We retrospectively reviewed medical records from dogs that presented for consultation between April 2012 and June 2019 and were diagnosed with nasal foreign body via rhinoscopy.

RESULTS

Forty-two dogs met the study's inclusion criteria. Thirty (71.4%; 30/42) were purebreds. Males accounted for 59.5% (25/42) of cases. The median age was 4.0 years old and 76.2% (32/42) were dogs up to 7 years of age. Mean bodyweight was 21.8 kg and dogs weighing more than 10 kg were overrepresented (78.6%; 33/42). Sneezing occurred in 78.6% (33/42) of cases. Foreign body retrieval was achieved by rhinoscopy in all cases. The foreign body was extracted from the right nasal cavity in 52.4% (22/42) of cases and from the left one in 42.9% (18/42). Two dogs (4.8%; 2/42) presented with one foreign body in each nasal cavity. Most nasal cavity foreign bodies (90.5%; 38/42) were grass awns. Three (7.2%; 3/42) were mineral and one (1/42) was fabric. Follow-up was documented for 35 patients, of which 97.1% (34/35) experienced resolution of clinical signs. Seven cases (16.7%; 7/42) were lost to follow-up.

CLINICAL SIGNIFICANCE

Nasal foreign bodies were more common in dogs up to 7 years of age and heavier than 10 kg. Sneezing was the primary clinical sign. The vast majority of foreign bodies were grass awns and rhinoscopy was an effective means of nasal cavity foreign body retrieval.

Upper digestive tract abnormalities in dogs with chronic idiopathic lymphoplasmacytic rhinitis

BACKGROUND

Chronic idiopathic lymphoplasmacytic rhinitis (CILPR) is a common inflammatory disorder of unknown etiology affecting the nasal cavity of dogs. The diagnosis is made by exclusion of other causes of nasal disease and specific therapeutic protocols are lacking. In human medicine, a relationship between CILPR and gastrointestinal clinical signs has been postulated, and remission of respiratory signs after clinical trials with medications for gastrointestinal disorders has been observed.

OBJECTIVES

To describe history, clinical presentation, endoscopic and histopathologic concurrent respiratory and digestive tract abnormalities, and to evaluate improvement of respiratory signs after treatment for gastrointestinal signs.

ANIMALS

Twenty-five dogs with CILPR.

METHODS

Prospective study. For inclusion, following information had to be available: respiratory and digestive clinical signs, airway and digestive tract endoscopic abnormalities, histologic evaluation of respiratory and gastrointestinal tract biopsy specimens, and clinical response to different treatment strategies.

RESULTS

Twenty-two dogs had endoscopic gastrointestinal lesions, whereas 13 dogs had concurrent gastrointestinal signs. Most esophageal and duodenal endoscopic abnormalities were classified as moderate or severe. Respiratory and gastrointestinal tract histologic evaluation identified mostly chronic inflammation. Remission or marked improvement of respiratory signs was observed in the majority of dogs treated only for gastrointestinal signs up to 12 months after endoscopy. No significant associations between treatments and follow-up information were found.

CONCLUSION AND CLINICAL IMPORTANCE

Nasal and upper digestive tract abnormalities coexist in some dogs with CILPR. Lack of standardized therapeutic protocols suggests caution when interpreting improvement in nasal clinical signs. Additional studies are needed to explore the possibility of a cause-effect relationship between the 2 processes.

Oral administration of voriconazole with surgical fungal plaque debridement for the treatment of sinonasal aspergillosis with cribriform plate lysis in three dogs

CASE DESCRIPTION

3 dogs with chronic sinonasal signs (sneezing, nasal discharge, or epistaxis [or a combination of signs]) were examined.

CLINICAL FINDINGS

For all 3 dogs, CT revealed variable degrees of nasal turbinate destruction and frontal sinus involvement with cribriform plate lysis. Fungal plaques were detected during rhinoscopy or sinusoscopy. Results of fungal culture (2 dogs) or cytologic examination of a plaque specimen (1 dog) supported a diagnosis of sinonasal aspergillosis.

TREATMENT AND OUTCOME

All dogs underwent surgical rhinotomy or sinusotomy (or both) for fungal plaque debridement followed by oral treatment with voriconazole and periodic physical examinations, clinicopathologic analyses, and assessments of serum drug concentrations for a period ≥ 22 weeks. All dogs had considerable to complete reduction of their clinical signs and tolerated voriconazole treatment with minimal adverse effects. Adverse effects included development of reversible neurotoxicosis (associated with high serum voriconazole concentration) and mildly high serum liver enzyme activities. The dosage of voriconazole administered to achieve therapeutic serum concentrations (2.5 to 3.3 mg/kg [1.1 to 1.5 mg/lb], PO, q 12 h) was substantially lower than dosages suggested by previously published studies in dogs. The 3 dogs remained clinically normal or had mild clinical signs after voriconazole discontinuation for follow-up times of 6 to 15 months.

CLINICAL RELEVANCE

Findings in these 3 dogs indicated that surgical fungal plaque debridement followed by oral treatment with voriconazole may be an effective treatment option for dogs with sinonasal aspergillosis and cribriform plate lysis. Further evaluation of this treatment regimen with repeated CT examinations and longer follow-up times is warranted.

CT findings in 20 dogs and six cats with confirmed nasal foreign bodies

The diagnosis and treatment of nasal foreign bodies usually includes a combination of rhinoscopy and imaging techniques, such as CT. The purpose of this retrospective, multicenter study was to describe the CT characteristics of nasal foreign bodies in dogs and cats and to determine if different nasal CT features exist between acute and chronic cases. Twenty dogs and six cats met the inclusion criteria. Eleven nasal foreign bodies (42%) were detected confidently with CT. The foreign body had a linear shape in 81% of cases and displayed a "tubular-like appearance" in 54% of cases. In five cases (19%), a foreign body was suspected but not clearly visible. Additional CT changes were present in the nasal passages in 96% of the cases. The presence of turbinate destruction (P = .021) and mucosal thickening (P = .014) on CT were associated with the presence of a chronic nasal foreign body. In this sample, the nature of the foreign body did not influence its visibility and was not associated with specific CT characteristics. Computed tomography may be useful in the investigation of nasal foreign bodies, however, a negative CT examination does not exclude their presence.

Canine Nasal Disease: An Update

Nasal disease in dogs is common and is often accompanied by chronic nasal discharge with or without other clinical signs. A thorough history and physical examination often guide the most appropriate choice of diagnostic testing to provide the best chance of attaining a diagnosis as to cause, and therefore, the most appropriate treatment. The purpose of this article is to guide the practitioner through a logical approach to the evaluation of dogs that are presented with signs of nasal disease.

Scopulariopsis brevicaulis Rhinosinal Infection in a Dog

A 1 yr old castrated male American Staffordshire terrier mix was treated for Scopulariopsis brevicaulis that was discovered during an evaluation of chronic rhinosinusitis. A sinusotomy was performed, with intraoperative infusion of amikacin-impregnated gel and systemic administration of postoperative amikacin. Antibiotic therapy was initially chosen because of historic culture of Mycoplasma. Fungal culture of the frontal sinus identified S. brevicaulis by combined phenotypic characterization and DNA sequencing after morphologic analysis failed to identify the organism. Systemic terbinafine therapy was instituted after fungal culture results were available. The patient recovered well and has had no clinical relapse of disease 3 yr after treatment. This is the first reported case of a fungal rhinosinusitis caused by S. brevicaulis in a dog. Reports of Scopulariopsis infections in humans indicate that treatment of S. brevicaulis infection is hampered by multidrug resistance; prognosis may be poor in people with invasive infections and is currently unknown in dogs. Multimodal therapy, including concurrent surgical and systemic intervention, may be necessary to optimize treatment success.

The evaluation of three treatment protocols using oral prednisone and oral meloxicam for therapy of canine idiopathic lymphoplasmacytic rhinitis: a pilot study

Background

Idiopathic lymphoplasmacytic rhinitis (LPR) is a common inflammatory disorder of the nasal cavity in dogs due to unknown etiology. It is characterised by non-specific clinical signs, including nasal discharge, epistaxis and breathing problems. Diagnosis is usually based on the histopathologic identification of infiltrating plasmocytes and lymphocytes in the nasal mucosa and the exclusion of other underlying diseases. Treatment strategies include glucocorticoids, non-steroidal anti-inflammatory drugs, antibiotics and antifungal medications. The aim of this study was to evaluate the efficacy of various therapeutic protocols for managing canine lymphoplasmacytic rhinitis based on the results of clinical, endoscopic and histological examinations, and to determine the relapse rate for LPR in dogs.

Twenty dogs of different breeds and both sexes, aged 1 to 14 years, were divided into four groups, each consisting of five dogs, including three experimental groups diagnosed with LPR and a control group.

The dogs from the first experimental group were administered prednisone orally at 1 mg/kg/day in the first 4 weeks and 0,5 mg/kg/day in the following 2 weeks. The second group of dogs was administered meloxicam orally at 0,1 mg/kg/day in the first 3 weeks, followed by prednisone at 1 mg/kg/day in the following 2 weeks and 0,5 mg/kg/day in the last week of the treatment. The dogs from the third experimental group were administered meloxicam orally at 0,1 mg/kg/day for 6 weeks. The control group of dogs was administered empty gelatin capsules (placebo) orally for 6 weeks. Clinical signs, endoscopic and histopathologic lesions were scored before and after treatment. Groups were compared using Chi- squared statistics in a 2 × 2 table for pre- versus post-treatment scores.

Results

Clinical signs persisted in the group treated with meloxicam and were mostly resolved in prednisone-treated dogs. However, endoscopic and histological changes were still observed in these two groups after treatment. The severity of all diagnostic features was reduced in the group treated with meloxicam for 3 weeks followed by prednisone for 3 weeks. The significant differences (p < 0.05) were noted between experimental and control groups. The dogs showed a statistically significant reduction in characteristics of the LPR before and after treatment, as measured by clinical signs (Group 1vs.4 p = 0.00, group 2 vs 4 p = 0.00, group 3 vs 4 p = 0,01), by endoscopy (1 vs 4 p = 0,01, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03), and by histopathology (groups 1 vs 4 p = 0,00, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03). The significant differences were noted between experimental groups, as measured by endoscopy (group 2vs 3 p = 0,04), and by relapse rate (groups 1 and 2 p = 0,03, groups 2 and 3 p = 0,01).

Conclusions

The three treatment protocols administered to dogs improved clinical, endoscopic and histological status. However, oral administration of meloxicam for 3 weeks, followed by prednisone for 3 weeks, appeared to be the most successful treatment. These patients remained asymptomatic for 6 months.

Emergence of nasal chondrosarcoma in a dog with nasal polyposis

Whilst the malignant transformation of nasal polyps or secondary development of nasal neoplasia after chronic inflammation is likely to be relatively rare, this potential complication should be considered, and the clinician should be vigilant for evidence of malignant transformation.

Leiomyoma in the nasal cavity of a dog

A 7-year-old, 34-kg, neutered male Labrador retriever was presented with a 1-year history of intermittent sneezing with occasional left-sided epistaxis. CT revealed a mass in the left nasal cavity. Histopathological analysis of rhinoscopy-guided tissue biopsies was consistent with chronic necrotic and ulcerative rhinitis. Surgical debridement by ventral rhinotomy was subsequently performed and histopathological diagnosis was leiomyoma. Complete resolution of the nasal discharge and reduced sneezing frequency were observed after surgery. Fourteen months postoperatively, CT detected no regrowth of the mass.

Severity of Nasal Inflammatory Disease Questionnaire for Canine Idiopathic Rhinitis Control: Instrument Development and Initial Validity Evidence

BACKGROUND

Effective treatments are needed for idiopathic chronic rhinitis in dogs, but assessment of efficacy requires a practical, quantifiable method for assessing severity of disease.

OBJECTIVES

To develop and perform initial validity and reliability testing of an owner-completed questionnaire for assessing clinical signs and dog and owner quality of life (QOL) in canine chronic rhinitis.

ANIMALS

Twenty-two dogs with histopathologically confirmed chronic rhinitis and 72 healthy dogs.

METHODS

In this prospective study, an online questionnaire was created based on literature review and feedback from veterinarians, veterinary internists with respiratory expertise, and owners of dogs with rhinitis. Owners of affected dogs completed the questionnaire twice, 1 week apart, to test reliability. Healthy dogs were assessed once. Data were analyzed using the Rasch Rating Scale Model, and results were interpreted using Messick's framework for evaluating construct validity evidence.

RESULTS

Initial item generation resulted in 5 domains: nasal signs, paranasal signs, global rhinitis severity, and dog's and owner's QOL. A 25-item questionnaire was developed using 5-point Likert-type scales. No respondent found the questionnaire difficult to complete. Strong psychometric evidence was available to support the substantive, generalizability, content, and structural aspects of construct validity. Statistical differences were found between responses for affected and control dogs for all but 2 items. These items were eliminated, resulting in the 23-item Severity of Nasal Inflammatory Disease (SNIFLD) questionnaire.

CONCLUSIONS AND CLINICAL IMPORTANCE

The SNIFLD questionnaire provides a mechanism for repeated assessments of disease severity in dogs with chronic rhinitis.

Pollen Allergies in Humans and their Dogs, Cats and Horses: Differences and Similarities

Both humans and their most important domestic animals harbor IgE and a similar IgE receptor repertoire and expression pattern. The same cell types are also involved in the triggering or regulation of allergies, such as mast cells, eosinophils or T-regulatory cells. Translational clinical studies in domestic animals could therefore help cure animal allergies and at the same time gather knowledge relevant to human patients. Dogs, cats and horses may spontaneously and to different extents develop immediate type symptoms to pollen allergens. The skin, nasal and bronchial reactions, as well as chronic skin lesions due to pollen are in principle comparable to human patients. Pollen of various species most often causes allergic rhinitis in human patients, whereas in dogs it elicits predominantly eczematous lesions (canine atopic dermatitis), in horses recurrent airway obstruction or hives as well as pruritic dermatitis, and in cats bronchial asthma and so-called cutaneous reactive patterns (eosinophilic granuloma complex, head and neck pruritus, symmetric self-induced alopecia). In human allergy-specific IgE detection, skin tests or other allergen provocation tests should be completed. In contrast, in animals IgE and dermal tests are regarded as equally important and may even replace each other. However, for practical and economic reasons intradermal tests are most commonly performed in a specialized practice. As in humans, in dogs, cats and horses allergen immunotherapy leads to significant improvement of the clinical symptoms. The collected evidence suggests that canines, felines and equines, with their spontaneous allergies, are attractive model patients for translational studies.