Marc Henroteaux

Eosinophilic bronchopneumopathy in dogs

Eosinophilic bronchopneumopathy was diagnosed in 23 young dogs. Clinical signs included cough, gagging, and retching in all dogs, dyspnea in 21 dogs (91%), and nasal discharge in 12 dogs (52%). The most common radiographic findings were a moderate to severe bronchointerstitial pattern (68%, 13 of 19 dogs). Bronchoscopic findings included the presence of abundant yellow-green mucus or mucopurulent material (70%, 16 of 23 dogs) and severe mucosal thickening with an irregular or polypoid appearance (52%, 12 of 23 dogs), with partial airway closure during expiration in 3 dogs (13%). Peripheral blood eosinophilia was noted in 14 of 23 dogs (61%). Inflammatory cells in brush or bronchoalveolar lavage fluid cytologic preparations comprised more than 50% eosinophils in 14 of 23 dogs (61%), and 20-50% eosinophils in 6 dogs (26%). Eosinophilic infiltration of the bronchial mucosa was observed in biopsies from 19 dogs and was graded as mild (37%, 7 dogs), moderate (32%, 6 dogs), or severe (32%, 6 dogs). The mean serum immunoglobulin A concentration was almost double that of a population of 20 healthy dogs of various breeds. Oral glucocorticoids were administered on alternate days with progressive tapering of the dose; the dosage at maintenance varied between 0.1 and 1.0 mg/kg every other day. No relationship was found between the duration of clinical signs and the maintenance dosage or the cytologic and histopathologic grades.

Laryngeal rhabdomyoma in a golden retriever

A three-year-old male golden retriever had had progressive dyspnoea, exercise intolerance, stridor, and a modified bark for five months. A mass 2 cm in diameter was present dorsal to the right side of the larynx. Histological examination revealed cross-striations in some elongated cells, consistent with a diagnosis of rhabdomyoma, a diagnosis which was confirmed by positive immunohistochemical staining for myoglobin and desmin. The mass could not be removed without total laryngectomy and a permanent tracheostomy and the dog was euthanased.

Effects of dobutamine on isovolumic and ejection phase indices of cardiac contractility in conscious healthy dogs.

The aim of this study was to determine cardiac contractility using indices derived from cardiac catheterisation in conscious healthy dogs during dobutamine infusion. Eight dogs were studied. An ECG was recorded together with left ventricular pressure and volume which were measured using a conductance catheter with an integrated microtip pressure sensor. Eight indices of left ventricular systolic performance were derived from these records. Measurements were realised under basal conditions and during an incremental dobutamine challenge. The maximal rate of rise in ventricular pressure (max dP/dt), max dP/dt divided by the developed pressure and the mean systolic ejection rate were the most sensitive indices to detect dobutamine induced changes in contractility with maximal percentage changes of 122+/-11 per cent, 130+/-7 per cent and 102+/-24 per cent respectively. Ejection fraction increased significantly during dobutamine infusion (maximal percentage change of 43+/-9 per cent) whereas the pre-ejection period (PEP) and the left ventricular ejection time (LVET) decreased significantly (maximal percentage change of -41+/-2 per cent and -28+/-3 per cent respectively). All these six indices were significantly correlated with each other. Conversely, the ratio PEP/LVET and the LVET corrected for heart rate dependency showed a maximal percentage change of only -10+/-1 per cent and -16+/-7 per cent, respectively, during the dobutamine infusion and were not significantly correlated with the other contractility indices. This study demonstrated the feasibility of the conductance method to determine cardiac contractility in conscious healthy dogs submitted to a pharmacological stress testing and provides control values for eight indices of left ventricular contractility during dobutamine infusion at increasing dosages.

Cardiac Performance in Conscious Healthy Dogs During Dobutamine Infusion

The aim of this study was to determine the cardiac performance of conscious healthy dogs during stimulation with dobutamine. Eight healthy unsedated beagle dogs were used. Cardiac output was measured by the thermodilution technique and blood pressures by extravascular pressure transducers. Dobutamine challenge at a dosage ranging from 27.5 to 50 micrograms kg-1 min-1 induced a significant rise in cardiac power index (CPI), cardiac index (CI), stroke index (SI) and heart rate (HR) and a significant decrease in pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR). The highest CPI was 2.05 times greater than its basal resting value. The CI was primarily responsible for this increase in CPI. The SI and HR contributed approximately 55 per cent and 45 per cent respectively of the maximal increase in CI.

Hormonal response to dobutamine cardiac stress testing in a conscious canine model of early left ventricular dysfunction induced by chronic rate overload.

The aims of this study were to investigate (1) hormonal activation before and during dobutamine cardiac stress testing (DST) in a canine model of early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP) and (2) the relationship between this hormonal profile and carnitine concentrations. Before the pacing period, the 6 dogs were assigned to 2 groups according their baseline total plasma carnitine concentration. A DST was performed on each dog before activation of the pacemaker and every 3 to 4 days during development of 3 progressive stages of ELVD (stages 1, 2 and 3). Plasma atrial natriuretic factor (ANF), angiotensin II (ANG II) and endothelin-1 (ET-1) levels were measured at the start and at the end of each DST. Effects of ELVD, DST and plasma carnitine concentration on these measurements were tested. The RRVP induced a significant increase of ANF and ANG II and a non significant trend toward increase of ET-1 in all dogs. Before the pacing period, ANF remained constant during the DST in dogs with normal total plasma carnitine concentration, while it significantly decreased in dogs with low total plasma carnitine concentration. Dobutamine stress testing induced a significant decrease in ANF in all dogs in ELVD. Dobutamine infusion induced a significant increase in ANG II in all dogs before as well as during the pacing period while ET-1 was unchanged. These results suggest that investigation of the hormonal profile before and after a dobutamine challenge might provide important diagnostic information in dogs with asymptomatic or mildly symptomatic cardiac dysfunction of different origins.

Nonresponsive generalized bacterial infection associated with systemic lupus erythematosus in a Beauceron.

A case of concurrent canine systemic lupus erythematosus (SLE) and generalized bacterial infection in a six-year-old female Beauceron is reported. The dog presented with purulent nasal and ocular discharges, skin lesions (including seborrhea, hyperkeratotic areas, and papules as well as ecchymoses around the eyes, on both sides of the pinnae, and on the vulva), generalized lymph node enlargement, a mitral murmur, and lameness. Later, facial swelling, a retrobulbar abscess, and a cough also developed. Occurrence of a generalized bacterial infection was established by culture of group-C, beta-hemolytic Streptococcus from the throat, the mouth, a biopsy site (popliteal lymph node area), the retrobulbar abscess, and the lung. The diagnosis of SLE was based on the clinical signs and particularly on the occurrence of antinuclear antibody (ANA) and antidoublestranded-desoxyribonucleic acid (ds-DNA) antibody. Interestingly, the latter type of antibodies were also detected in two young female puppies whelped by this dog. Salient histological findings included an extreme cell depletion of the lymph nodes and spleen and severe pneumonitis and peribronchiolitis. The results of this case indicate that a definite diagnosis of canine SLE can, at times, be made on the basis of the presence of serum ANA and ds-DNA antibodies.