Eosinophilic bronchitis, eosinophilic granuloma, and eosinophilic bronchopneumopathy in 75 dogs (2006-2016)

Presumed pseudo-Pelger-Huët anomaly and basophilia secondary to chronic lymphocytic leukemia in a dog

A 10-year-old neutered male Maltese dog was presented for an investigation of lymphocytosis. The dog was up-to-date on vaccinations and deworming. Physical examination did not reveal any significant abnormalities. A complete blood cell count (CBC) showed mild leukocytosis with moderate lymphocytosis, basophilia, and moderate neutropenia, but no significant left shift or toxic change. Serum biochemistry and urinalysis were unremarkable. All performed tests for infectious agents common in this geographical region were negative. No significant abnormalities were found on abdominal ultrasound examination. Multiparametric flow cytometry of peripheral blood showed a CD8+ T-cell lymphocytosis, and PCR for antigen receptor rearrangement revealed a clonal expansion of the T-cell receptor gamma chain genes. A clinical diagnosis of chronic lymphocytic leukemia (CLL) was made, and follow-up was recommended. On Day 48 post-presentation, the CBC showed mild non-regenerative anemia (NRA), moderate leucocytosis due to moderate to marked lymphocytosis, basophilia, and a marked increase in hyposegmented neutrophils with mild toxic change in the absence of neutrophilia or neutropenia. Treatment with chlorambucil and prednisolone was initiated. On Days 87 and 197 post-presentation, the CBC showed mild NRA, with progressively decreasing numbers of hyposegmented neutrophils. The dog remained without clinical signs. Basophilia and probable pseudo-Pelger-Huët anomaly were possibly secondary to CLL. To the authors' knowledge, this is the first report of these two hematologic conditions secondary to CLL in dogs. Recognition of a pseudo-Pelger-Huët anomaly is clinically relevant to avoid misinterpretation as a marked left shift due to severe inflammation and prevent unnecessary urgent therapeutic actions.

Feline herpesvirus-1-related multiple respiratory eosinophilic nodules in an adult cat receiving long-term oral prednisolone

Case summary

A 10-year-old male castrated domestic shorthair cat was presented for evaluation of a 3-day history of increased inspiratory effort. The cat had received prednisolone 1 mg/kg PO q24h for 1 year due to chronic diarrhea. On physical examination, the patient exhibited severe stridor, intermittent open-mouth breathing and bilateral mucopurulent nasal discharge. Subcutaneous emphysema was palpated over the dorsal cervical region. Mild hypoventilation (PvCO2 55.1 mmHg; approximate reference interval 35-45 mmHg) was identified. Cervicothoracic radiographs showed marked gas tracking within cervical soft tissues with concurrent laryngeal thickening, pulmonary nodules, a bronchial pulmonary pattern, pneumomediastinum and aerophagia. The cat was hospitalized and treated overnight with oxygen and intravenous fluid therapy before anesthesia the next day. On laryngoscopy, a large tracheal mass was observed arising from the right subglottic region and was removed using biopsy forceps. CT revealed an additional mass at the level of the tracheal bifurcation causing marked luminal narrowing of the trachea and proximal main bronchi. The cat made a good initial recovery, although moderate stridor persisted. Five days later, the cat was re-examined due to recurrence of respiratory distress and orthopnea, and the owner elected euthanasia. Histopathology revealed severe nodular obstructive eosinophilic plasmacytic laryngotracheitis with intranuclear inclusion bodies positive for feline herpesvirus-1 on immunohistochemistry.

Relevance and novel information

This report describes the presentation and management of a cat with respiratory distress secondary to intratracheal eosinophilic masses caused by feline herpesvirus-1. Although the outcome was ultimately unsatisfactory, to the authors' knowledge, this clinical presentation has not been previously reported.

Hematologic Abnormalities and Diseases Associated with Moderate-to-Marked Basophilia in a Large Cohort of Dogs

Basophilia is a rare hematologic finding in dogs. This research aimed to describe the hematologic and clinical characteristics of dogs with moderate-to-marked basophilia. CBC reports with blood smear examinations from dogs presented to the North Carolina State University Veterinary Teaching Hospital were retrospectively reviewed for basophilia (>193 cells/µL). We classified basophilia as moderate when counts were ≥500 cells/µL and marked when they reached ≥1000 cells/µL. We compared the hematologic and clinical profiles of dogs with moderate-to-marked basophilia (the basophilia group) to those without basophilia, serving as our control group. In addition, we investigated differences between dogs with marked basophilia versus those with moderate basophilia, as well as between dogs in the basophilia group with and without concurrent eosinophilia. Diseases associated with moderate-to-marked basophilia included eosinophilic lung disease (p < 0.0001), leukemia/myeloproliferative neoplasms (p = 0.004), parasitic infection (p = 0.004), mast cell tumor (p = 0.005), and inflammatory bowel disease (p = 0.02). Overall, dogs with marked basophilia had a lower frequency of inflammatory diseases (51% vs. 70%, p = 0.009) and a higher frequency of neoplastic diseases (48% vs. 26%, p = 0.003) compared to those with moderate basophilia. In the basophilia group, concurrent eosinophilia was only seen in 36% of dogs. Dogs with concurrent eosinophilia were more often diagnosed with inflammatory diseases (77% vs. 58%, p = 0.006), with fewer diagnoses of neoplasia (19% vs. 40%, p = 0.001), compared to dogs without concurrent eosinophilia. The findings of this study offer veterinary clinicians valuable guidance in determining diagnostic priorities for dogs with moderate-to-marked basophilia.

Diagnostic Contribution of Bronchoalveolar Lavage Sampling and Fungal Culture in a Dog With Pulmonary Coccidioidomycosis

A 7-year-old, male neutered, Miniature Australian Shepherd from Arizona was presented for evaluation of a 3-month history of progressive cough. Thoracic radiographs revealed a focal alveolar pulmonary pattern and suspected tracheobronchial lymph node enlargement. Serum anti-Coccidioides spp. IgM/IgG antibodies were not detected by agar gel immunodiffusion performed by 2 different reference commercial veterinary laboratories approximately 3.5 and 3.75 months after respiratory tract signs were first noted. The dog failed to respond to empiric therapy with a cough suppressant and various antibiotics. Tracheobronchoscopy and bronchoalveolar lavage (BAL) were subsequently performed and cytological examination of the BAL fluid identified marked neutrophilic inflammation characterized by mildly degenerate neutrophils and no infectious organisms. Bacterial cultures were negative but fungal cultures revealed growth of Coccidioides spp. Clinical signs improved shortly after initiation of fluconazole administration and the dog achieved long-term sustained clinical remission. Here, we provide a description of a dog with pulmonary coccidioidomycosis diagnosed with fungal culture of BAL fluid. Airway sampling with cytological examination and fungal culture should be considered in dogs with persistent respiratory related clinical signs, negative antibody serology, and that have lived in or traveled to endemic areas.

[Inhalation therapy in dogs and cats with chronic lower airway disease - a literature review]

Chronic respiratory diseases are prevalent medical conditions in dogs and cats requiring lifelong treatment. Mainstay of therapy for chronic inflammatory respiratory diseases are glucocorticoids. Concurrent treatment with bronchodilators may be necessary to control clinical signs sufficiently. Due to the successful use in people as well as subsequent reduction of adverse effects of long-term glucocorticoid therapy, inhalative therapy has become increasingly important in veterinary medicine as well. Primarily spacers or valved holding chambers, in combination with metered dose inhalers, are used in dogs and cats. The technical properties of these devices, as well as their use and maintenance will be described in the following article. Furthermore, the existing literature regarding efficacy of inhalative medications for therapy of chronic inflammatory airway diseases in dogs and cats will be summarized.

Peripheral blood eosinophilia in dogs: Prevalence and associated diseases

BACKGROUND

Canine eosinophilia has not been evaluated over the last two decades. As in human local differences, changes in the prevalence and associated diseases over time can be expected.

OBJECTIVE

This study aims to determine the prevalence and causes of marked blood eosinophilia in dogs.

METHODS

Retrospective study. A total of 317 clinical histories of dogs with an eosinophil concentration > 1.5 × 109 /L (marked eosinophilia) between 2013 and 2017 were evaluated. Patients were allocated to 10 groups according to their major clinical findings.

RESULTS

Eosinophilia was present in 1,592 of 10,829 dogs (14.7%); it was mild (0.8-1.49 × 109 /L) in 78.4%, moderate (1.5 - 4.9 × 109 /L) in 20.5% and severe (> 5 × 109 /L) in 1.1% of cases. Rottweilers were overrepresented (16.1%). Of 317 cases with marked eosinophilia, 19.6% had neoplasia, 19.1% gastrointestinal disorders, 13.6% health check, 10.4% endoparasites, 6% respiratory, 5.4% neurologic, 5.4% dermatologic, 4.8% urogenital, 3.2% endocrine disorders and 12.6% miscellaneous. Lymphomas (29%) and mast cell tumours (12.9%) were the most frequent tumours in the neoplasia group. A total of 72.6% of tumour-bearing dogs were older than 8 years, while 63.6% of dogs had endoparasites, and 86% of apparently healthy dogs were younger than 5 years. Eosinophilia was significantly higher in patients with respiratory disorders (p < 0.0146). Leukocytosis was found in 50.2% of cases.

CONCLUSION

Malignancy was the most common cause of marked blood eosinophilia in older dogs and endoparasitism in younger dogs. Eosinophilia was common in apparently healthy young dogs and may be related to undiagnosed parasitic infestations.

Pulmonary eosinophilic granulomatosis in a dog

A two-year-old female Prague Ratter dog was presented for evaluation of cough, exercise intolerance and worsening dyspnea. A previous treatment with antibiotics did not resolve the clinical signs. A diagnostic approach revealed peripheral eosinophilia, endoscopic bronchial changes, and bronchoalveolar lavage with eosinophilic inflammation. Thoracic radiographs revealed a solitary mass and bilateral interstitial lung pattern. These radiographic findings were confirmed by computed tomography and ultrasound-guided biopsy of the lung mass. Treatment with prednisolone and azathioprine was initiated. Two months afterwards, the granuloma was no longer detectable radiographically. All medication was gradually discontinued after nine months and currently, after almost three years, the dog remains free of clinical signs.

Presence of bronchial nodules, younger age, and heavier body weight are associated with a diagnosis of eosinophilic lung disease in dogs with cough

OBJECTIVE

To describe the association between a diagnosis of eosinophilic lung disease (ELD) in dogs with signalment and bronchoscopic features and evaluate the accuracy of visualization of nodules for the diagnosis of ELD.

ANIMALS

781 dogs with cough that underwent bronchoscopy between 2014 and 2016.

PROCEDURES

Data were extracted from the medical records of each included dog. Multivariable logistic regression was performed to investigate associations between ELD and patient characteristics.

RESULTS

ELD was diagnosed in 113 (14.5%) dogs. More than 3 nodular lesions of the bronchial mucosa were detected in 64 (8.2%) dogs. The odds of having ELD were greater in dogs with nodules (adjusted OR [aOR], 26.0; 95% CI, 13.0 to 52.0) and static bronchial collapse (aOR, 2.3; 95% CI, 1.1 to 4.6), and lower in dogs having focal versus diffuse inflammation (aOR, 0.05; 95% CI, 0.01 to 0.37). The odds of having ELD decreased for each 1-year increase in age (aOR, 0.86; 95% CI, 0.80 to 0.92), and increased for each 1-kg increase in weight (aOR, 1.04; 95% CI, 1.01 to 1.06). Visualization of nodules during bronchoscopy had a overall accuracy of 89.4% (95% CI, 87.0% to 91.4%), sensitivity of 41.6% (32.4% to 51.2%), and specificity of 97.5% (96.0% to 98.5%) for a diagnosis of ELD.

CLINICAL RELEVANCE

On the basis of high specificity and negative predictive value, lack of visualization of bronchial nodules during bronchoscopy can be used to preliminarily rule out ELD. However, visualization of bronchial nodules does not imply presence of ELD. This could be especially relevant when results of BAL cytology are available several days after the actual bronchoscopy.

Eosinophilic pulmonary granulomatosis resembling a pulmonary carcinoma in a dog in Hong Kong

Background

Canine Eosinophilic Pulmonary Granulomatosis (EPG) is a severe form of eosinophilic pulmonary disease that carries a guarded prognosis, responds poorly to therapy and recurs frequently. Most studies have reported a caudal lobar pulmonary distribution and a poorer prognosis in idiopathic cases.

Case Description

A 7-year-old dog was presented for persistent cough, hyporexia, and weight loss. Eosinophilia and basophilia were transiently present, and an antigen test for heartworm disease was negative. Radiographic studies, followed by a computed tomography (CT) scan revealed nodular lesions and a large mass in the left cranial lobar region suggestive of neoplasia. Cytological and histopathological evaluation was consistent with EPG. The dog responded positively to corticosteroids and has since remained free of disease.

Conclusion

EPG in dogs can resemble primary pulmonary neoplasia with secondary intra-pulmonary metastasis. Contrary to previous reports, idiopathic EPG can present with a cranial pulmonary distribution and respond positively to therapy.

Association between respiratory clinical signs and respiratory localization in dogs and cats with abnormal breathing patterns

The diagnostic values of respiratory signs have been under-investigated in pets. The study aim was to explore commonly assumed associations between respiratory signs and disease localization in pets with abnormal breathing patterns (ABP). Dogs and cats with ABP presenting to three hospitals were included if investigations permitted disease localization. Hypothesized associations between respiratory signs and disease location were evaluated via mixed-effects logistic regression. Sensitivity, specificity, and positive diagnostic likelihood ratio were calculated. One-hundred and fifteen dogs and 49 cats with ABP were recruited. Confirmed associations included: inspiratory effort with extra-thoracic airway disease (odds ratio [OR], 9.1; 95% confidence interval [95% CI] 3.0-27.2); expiratory effort with intra-thoracic airway disease (OR, 6.5; 95% CI, 2.3-18.1); paradoxical breathing and attenuation of heart/lung sounds with pleural space disease (paradoxical breathing: OR, 4.5; 95% CI 1.7-12.1; sound attenuation: OR, 11.5; 95% CI 4.0-33.3); decreased nasal airflow and stertor with nasal/pharyngeal disease (nasal airflow: OR, 26.2; 95% CI 8.1-84.8; stertor: OR, 155.2; 95% CI 24.9-968.8); stridor with laryngeal or tracheal disease (laryngeal disease: OR, 39.9; 95% CI 7.6-209.0; tracheal disease: OR, 32.4; 95% CI 4.2-248.0); tracheal sensitivity with bronchial disease (OR, 3.8; 95% CI 1.5-9.6); crackles with pulmonary or bronchial disease (pulmonary disease: OR, 5.4; 95% CI 2.1-13.8; bronchial disease: OR, 3.9; 95% CI 1.6-9.8); and goose honking with tracheal disease (all dogs with goose honking had tracheal involvement). Select respiratory signs provide guidance to localize and prioritize causes of the underlying respiratory disease in pets, allowing targeted interventions in animals with ABP.

Topographical distribution and radiographic pattern of lung lesions in canine eosinophilic bronchopneumopathy

OBJECTIVES

To evaluate the radiographic lung pattern and topographical distribution in canine eosinophilic bronchopneumopathy.

MATERIALS AND METHODS

Medical records were retrospectively reviewed for dogs diagnosed with eosinophilic bronchopneumopathy. Lateral thoracic radiographs were examined for the presence of increased radiopacity, classification of pattern, topography of lung changes (cranioventral, perihilar, caudodorsal, caudoventral) and severity of pulmonary lesions.

RESULTS

Forty-four cases were identified with the Labrador retriever being the most commonly affected breed; there was a mean age of 5 years and an equal gender distribution. Coughing was the most common clinical sign. Circulating eosinophilia was present in 39% of dogs, with a mean peripheral eosinophilia of 5.1×10⁹ cells/L and a mean bronchoalveolar lavage fluid eosinophilia of 40%. Eighty percent of dogs had an abnormal lung pattern in at least one of the four lung fields; the remaining had normal thoracic radiographs. The most common patterns were a bronchial and a bronchointerstitial pattern, with 41 and 89% distribution to the caudodorsal lung field, respectively.

CLINICAL SIGNIFICANCE

A bronchial and bronchointerstitial pattern are the most common radiographic lung patterns seen in canine eosinophilic bronchopneumopathy with these patterns most frequently topographically distributed to at least the caudodorsal lung field. Furthermore, within the caudodorsal lung field, a bronchointerstitial pattern predominates. This radiographic and topographical finding may allow eosinophilic bronchopneumopathy to take precedence on a differential diagnoses list before confirmatory bronchoalveolar lavage fluid sampling.

Clinical features and long-term follow-up of 70 cases of canine idiopathic eosinophilic lung disease

BACKGROUND

Canine idiopathic eosinophilic lung disease (ELD) is sparsely documented in the literature.

METHODS

Clinical presentation and outcome of dogs diagnosed with ELD (eosinophilic bronchitis or eosinophilic bronchopneumonia) were reviewed. Subgroups were made based on chronicity of clinical signs and findings of thoracic imaging: NCI (no changes in thoracic imaging), BRON (bronchial/peribronchial pattern), INT (bronchointerstitial/interstitial/alveolar).

RESULTS

Seventy cases were included. There were more young to adult, crossbreed and female dogs. Compared with the other two groups NCI dogs showed lower bronchoalveolar lavage fluid eosinophilic pleocytosis and absence of circulating eosinophilia, bronchiectasis or death due to respiratory disease. All dogs responded clinically to corticosteroids. Median treatment duration was four months. Remission (no clinical signs after treatment discontinuation for >one month) and long-term remission (>six months) was achieved in 60 per cent, and 51 per cent of patients, respectively. Relapse occurred in 26 per cent of cases after remission but was rare (3 per cent) after long-term remission. The one-year, two-year and four-year survival to death due to respiratory disease was 98 per cent, 97 per cent and 91 per cent, respectively.

CONCLUSION

Prognosis and initial clinical response for ELD was generally good although achievement of long-term remission was only seen in 51 per cent of dogs. Different outcomes based on chronicity of signs, corticosteroid dose, thoracic imaging abnormalities and other clinical variables were not appreciated.

Eosinophilic bronchitis, eosinophilic granuloma, and eosinophilic bronchopneumopathy in 75 dogs (2006-2016)

Background

Eosinophilic lung disease is a poorly understood inflammatory airway disease that results in substantial morbidity.

Objective

To describe clinical findings in dogs with eosinophilic lung disease defined on the basis of radiographic, bronchoscopic, and bronchoalveolar lavage fluid (BAL) analysis. Categories included eosinophilic bronchitis (EB), eosinophilic granuloma (EG), and eosinophilic bronchopneumopathy (EBP).

Animals

Seventy‐five client owned dogs.

Methods

Medical records were retrospectively reviewed for dogs with idiopathic BAL fluid eosinophilia. Information abstracted included duration and nature of clinical signs, bronchoscopic findings, and laboratory data. Thoracic radiographs were evaluated for the pattern of infiltrate, bronchiectasis, and lymphadenomegaly.

Results

Thoracic radiographs were normal or demonstrated a bronchial pattern in 31 dogs assigned a diagnosis of EB. Nine dogs had intraluminal mass lesions and were bronchoscopically diagnosed with EG. The remaining 35 dogs were categorized as having EBP based on radiographic changes, yellow green mucus in the airways, mucosal changes, and airway collapse. Age and duration of cough did not differ among groups. Dogs with EB were less likely to have bronchiectasis or peripheral eosinophilia, had lower total nucleated cell count in BAL fluid, and lower percentage of eosinophils in BAL fluid compared to dogs in the other 2 groups. In contrast to previous reports, prolonged survival (>55 months) was documented in dogs with EG.

Conclusions and Clinical Importance

Dogs with eosinophilic lung disease can be categorized based on imaging, bronchoscopic and BAL fluid cytologic findings. Further studies are needed to establish response to treatment in these groups.