Atualização sobre a epidemiologia de Dirofilaria immitis na América do Sul e no México: revisão de literatura

Dirofilaria immitis é um nematoide de ampla distribuição geográfica, que ocorre com maior frequência em áreas quentes e úmidas do planeta. O primeiro registro de sua ocorrência na América do Sul foi realizado em 1878, no Brasil. Naquela época os registros eram poucos e raramente de fácil obtenção, razão pela qual reuni-los facilitará a recuperação da memória ao longo dos anos. Quatro bases de dados (Scopus, MEDLINE, LILACS e PubMed) foram estudadas utilizando-se as palavras-chave “Dirofilaria” ou “heartworm”, os nomes dos países da América do Sul e o México. Nenhum registro foi encontrado para quatro países (Bolívia, Equador, Guiana Francesa e Uruguai) e para outros três (Suriname, Guiana e Paraguai) os registros eram antigos. Apenas o Chile é o território onde houve estudos registrados com ausência do parasita. Os outros países (México, Peru, Colômbia, Venezuela, Argentina e Brasil) apresentam registros com frequência variável no tempo ou no espaço. Assim, as informações reunidas indicam que infecções por D. immitis ocorrem na maior parte da América do Sul e no México e que os médicos veterinários devem instituir programas preventivos para garantir cuidados médicos de qualidade aos pacientes e para proteger a saúde destes e de suas famílias.Dirofilaria immitis (Leidy, 1856; Raillet & Henry 1911) is a parasite that is widely disseminated around the globe, with a higher prevalence in warm, humid climates. The first report of its occurrence in South America is from 1878 in Brazil. At that time, reports were scarce and difficult to retrieve – therefore, gathering them will facilitate record-keeping over time. Four databases were searched (Scopus, MEDLINE, LILACS, and PubMed) and the search keywords were “Dirofilaria” or “heartworm” and the countries’ names. Four countries lacked reports (Bolivia, Ecuador, French Guiana, and Uruguay) and other three (Suriname, Guyana, and Paraguay) had only old reports. Chile was the only country in which studies were conducted over time, and no infected dogs were registered. For the other six countries (Mexico, Peru, Colombia, Venezuela, Argentina, and Brazil), reports showed that the infection frequency varied over time and with the surveyed area. Therefore, the information indicates that D. immitis is established, and veterinarians must institute preventive programs to optimally care for their patients and protect the health of their families

Recurrent Spontaneous Pneumothorax in a Maltese Dog with Endogenous Lipoid Pneumonia

Background: Pneumothorax is a clinical condition which can cause respiratory distress. It can have as its origin traumatic causes or even classified as spontaneous, mainly related to diseases of the lung parenchyma. Lipoid pneumonia is rarely described in dogs, and it is characterized by globules of lipid in the alveolar spaces. Endogenous lipoid pneumonia (EnLP) occurs when lesions on pulmonary cells release cholesterol and other lipids in the alveoli. There is no clinical approach established for EnLP in veterinary patients. The aim of this report is to describe a case of a young Maltese dog, with recurrent spontaneous pneumothorax in which EnLP was diagnosed Post mortem.Case: A 2-year-old sexually intact male Maltese dog was evaluated for restrictive dyspnea. Clinicopathologic findings included cyanotic, muffled chest auscultation with hypersonic thoracic percussion. Chest x-ray demonstrated an increase in pleuropulmonary radio transparency and a floating-looking heart, indicating pneumothorax. Complete blood counts andbiochemical panel results were normal. Dirofilaria immitis antigen test results were negative. Computed tomography demonstrated slightly hyper-expanded pulmonary fields, with slightly enlarged reticular marking with areas of mild multicentric panlobular emphysema and a fracture on the sixth left rib. The treatment was focused on improving the breathing pattern through sedation, supplementation with oxygen, and thoracentesis. Owing to the reserved prognosis of the case, the unknown etiology of the recurrent pneumothorax, and the clinical worsening of the patient, the owner opted for euthanasia. Necropsy displayed multiple, circular whitish areas in the lungs, distributed over the surface of all lobes. Histopathological examination revealed pulmonary tissue with the subpleural micronodular foci, multifocal to coalescent, with a moderate accumulation of foamy intra-alveolar macrophages, occasionally multinucleate, associated with cholesterol crystals compatible with endogenous lipid pneumonia. Discussion: The patient presented with clinical signs and physical examination characteristics of pneumothorax at the first visit. After the pneumothorax diagnosis, and clinical stabilization of the patient. No predisposing factor for the formation of the pneumothorax was identified as the radiography revealed only bronchitis and blood tests were normal, the patient was thus discharged after 24 h, with the recommendations for observing the breathing pattern. Initially, spontaneous pneumothorax was suspected. The antibiotics were administered since bacterial pneumonia, although not confirmed on chest x-ray, is the main cause of pneumothorax in dogs is lung parenchyma disease. With the worsening of the clinical condition of the patient, CT was performed and did not demonstrate any findings that would justify the presence of pneumothorax. Despite the placement of the chest tube for facilitating the management of thoracentesis, there was no stabilization of the condition, enhancing the frequency of centesis procedures, which led to the decision to euthanize. The microscopic examination of the pulmonary alterations was decisive for the diagnostic conclusion. The visualization of the accumulation of foamy intra-alveolar macrophages, occasionally multinucleate, associated with cholesterol crystals, was responsible for the diagnosis of EnLP. This condition is rarely described in dogs and as in the present report, it is a noninfectious inflammatory condition, characterized by intra- or extracellular globules of lipid in the alveolar spaces. In the present report, although it was not possible to determine the etiology of EnLP, we can conclude that although rare, it can affect dogs and can generate severe clinical repercussions

Nutraceuticals for Dissolving Nephrolites in Cats

Background: Nephrolithiasis is a condition frequently observed in felines, with or without concomitant chronic kidney disease, constituting the major cause of ureteral obstruction and causing progressive damage to the renal parenchyma. About 90% of nephrolites are composed of calcium oxalate, which cannot dissolve, and its incidence has increased substantially in recent years, along with its recurrence. There are functional foods known as nutraceuticals provides health benefits such as renoprotection. Due to these benefits and the high prevalence of nephrolithiasis in feline species, the present study aimed to evaluate the efficacy of the association of some nutraceuticals in the dissolution of nephrolites.Materials, Methods & Results: The included cats had an ultrasound diagnosis of nephrolithiasis that, on clinical examination, showed: (i) the absence of previous or concomitant treatment for urinary infections and/or vesical and renal lithiasis; (ii) absence of genitourinary clinical manifestations; (iii) absence of obstructive processes; and (iv) absence of concomitant ureterolithiasis. We separated 51 cats with nephrolithiasis into 2 groups: control (n = 12) and study (n = 39). The control group received a placebo and the study group, nutraceuticals (magnesium chelate, resveratrol, vitamin K2, docosahexaenoic acid, and eicosapentaenoic acid). Laboratory tests (blood and urine) and abdominal imaging (ultrasound) were performed at day 0 and 30 days after enrollment. Monitoring the therapeutic efficacy in both groups was performed on day 30 for the CG and on days 30, 60, and 90 for the EG. The CG cats, after this step, were referred to surgery or to the EG, with prior authorization from their tutors. The diameter of nephrolites was significantly different before and after treatment, indicating a reduction in nephroliths over time. During the use of the nutraceutical formulation by the EG and use of placebo by the CG, there were no clinical and/or laboratory manifestations of side effects.Discussion: The dissolution of nephrolites was correlated with the synergism promoted by the combination of nutraceuticals and not with the individual beneficial action of each nutraceutical since nutraceuticals have individually been used in isolation for a long time in veterinary medicine without having yielded the same benefit. Those undissolved were attributed to a different type of mineral composition than the one associated with the nutraceutical compound in this study, such as struvite or ammonium urate, of mixed composition or comprising solidified dried blood, which has shown an increasing increase in use in recent years. The dissolution of nephrolites was correlated with the synergism promoted by the combination of nutraceuticals and not with the individual beneficial action of each nutraceutical since nutraceuticals have individually been used in isolation for a long time in veterinary medicine without having yielded the same benefit. The undissolved nephrolites were attributed to the nephrolites that obtained partial dissolution at the end of 90 days, in that they possibly needed a longer time to obtain complete dissolution or that they present another mineral composition in their nucleus; that is, it is a compound-type urolith. The nutraceutical compound proved to be effective in the dissolution of nephrolites in the cats included in this study, and the time of use (up to 90 days) showed no negative influence on the clinical or laboratory tests during the entire treatment period.Keywords: cats, food supplement, functional foods, natural products, nephrolithiasis, nutraceuticals

Unilateral Atrial Ectopic Rhythm in a Golden Retriever

Background: Atrial ectopic rhythm is a type of supraventricular arrhythmia, originating in two distinct points in the atrial region. In the electrocardiographic (ECG) tracing, it is represented by independent depolarizations of sinus P waves and ectopic P waves. The occurrence of this disorder is rare, and the diagnosis criteria are the presence of the described waves within the basal rhythm. In humans, there have been reports related to severe heart failure with an unfavorable prognosis. The present report aimed to describe the clinical case of a dog with unilateral atrial ectopic rhythm without any underlying cardiac disorder.Case: A 8-year-old male golden retriever was brought to a veterinary clinic for a preoperative evaluation for lipoma removal in the right forelimb. On clinical examination, the owner stated that the patient was active, with no signs of easy fatigue or cough. The canine displayed normophagy, normodipsia, normoquezia, and normouria. On physical examination, he demonstrated a lymphatic temperament with tachypnea. The temperature and capillary filling time were within the normal range, with a normokinetic pulse. Cardiac auscultation revealed a mild grade I/VI murmur in mitral focus and an 80-bpm heart rate. Respiratory auscultation revealed the presence of harshy lung sounds. The cough reflex was positive; the Piparote test, negative. The blood test showed no noticeable changes in blood count and serum biochemistry. Systemic systolic blood pressure was 120 mmHg. On radiographic examination, no evidence of heart or lung abnormalities were identified. After the clinical evaluation, an ECG examination was performed; a unilateral atrial ectopic rhythm was observed with different frequencies between atrial and ventricular rhythm and with P (164°) and P waves (80°). On echocardiographic examination, no morphological abnormalities were seen, though trivial mitral insufficiency was identified in a color Doppler study. Blood was collected to measure electrolytes to check for possible electrolytic abnormalities; the results were within the normal range. The patient was released for and remained stable throughout the procedure, maintaining the rhythm detected during the transoperatory time. Upon reassessment in a new ECG examination, the arrhythmia persisted, suggesting that a primary lesion in the atrial tissue was present.Discussion: An atrial ectopic rhythm diagnosis requires a detailed study with the aim of ruling out heart diseases that may affect the propagation of the cardiac stimulus. However, no morphological or functional abnormalities of note that justified triggering stimuli for the ectopic rhythm were observed. In addition, based on the echocardiographic evaluation, myocardial function was preserved, supporting the canine’s release for the procedure. The suspicion of hydroelectrolytic alteration and hypoxia was present after discarding structural causes, though it was discarded due to normal laboratory results. The presence of ectopic P waves was due to the non-interference in the sinus P’ waves; consequently, they were found in the sinus heart rhythm. Upon assessing the ectopic P wave frequency, the atrial rhythm frequency was higher than the heart rate, juxtaposing the different irregular intervals within the atrial cycle. The rhythm alone may explain that its severity can be linked to the physical findings. This indicated that they did not influence the presentation of ectopia since the cardiac output, controlled by the sinus rhythm part, was responsible for maintaining the rhythm and the demand of the organism; the electrical conduction system, responsible for atrial systole, represents 15-25% of the blood ejection for the ventricular filling. Patients with rhythm disorders as described need guidance and follow-up for the early detection of clinical signs resulting from the destabilization of the condition.Keywords: atrial dissociation, supraventricular arrhythmia, electrocardiogram, dogs

Brachycephalic Syndrome in Dogs - Endoscopic Findings in the Airways

Background: Brachycephalic dogs have several abnormalities in the airways, which generate clinical manifestations that impair the quality of life of these animals. Primary alterations promote airflow obstruction and increase intraluminal negative pressure, causing secondary alterations due to a cycle of inflammation with consequent obstruction. With the onset of inflammation and other alterations in the airways, clinical manifestations can be observed, such as snoring, reverse sneezing, coughing, dyspnea, cyanosis, syncope, and vomiting. Endoscopic examination of the airways allows visualization and diagnosis of morphological changes in these animals. This study aimed to evaluate the endoscopic findings of the airways and determine the quantitative and qualitative assessment of the severity of clinical manifestations in 14 dogs with brachycephalic syndrome (BS). Materials, Methods & Results:  Historical and anamnesis data and clinical, respiratory, and digestive manifestations were collected from the owners’ reports. The clinical manifestations were classified as mild, moderate, or severe. All animals were subjected to endoscopy of the airways, and image findings were grouped according to the anatomical site where they were observed, then the abnormalities were correlated with the severity of the clinical manifestations. When comparing the frequency of endoscopic abnormalities with the severity of clinical manifestations, it is interesting to observe that animals with severe disease more frequently presented the following alterations: prolongation and thickening of the soft palate, laryngeal changes, presence of hyperemia, lymphoid hyperplasia and polyps in the nasopharynx, hypoplasia and presence of tracheal secretion and thickening of the dorsal tracheal muscle; bronchial collapse, hypoplasia of the main bronchi and bronchial hyperemia and the presence of aberrant nasal turbinates. Comparison between the means of nonparametric variables was performed using the Mann-Whitney test, with a 5% significance level.  Discussion: A higher frequency of French Bulldog dogs included in the study was observed, probably due to their greater popularity, although any brachycephalic dog may be affected by BS. Considering that nostril stenosis is a congenital alteration, which is usually diagnosed early, and since the animals included in the study were dogs referred for the rhinoplasty procedure the higher frequency of young dogs in the study was not surprising. The results revealed a significant difference in the endoscopic findings with the severity of the clinical manifestations in different variables, such as prolongation and thickening of the soft palate, eversion of the laryngeal saccules, presence of laryngeal inflammation and collapse, presence of polyps or lymphoid hyperplasia in the nasopharynx, thickening of the dorsal muscle of the trachea, polyps in the trachea and hypoplasia in addition to bronchial hyperemia. The larynx was the most affected anatomical site, with alterations present in 92.8% of the evaluated dogs. Based on these findings, it can be concluded that airway obstruction caused by primary alterations can cause secondary alterations, with consequent clinical manifestations in brachycephalic dogs it is possible to suggest that dogs with this syndrome may present severe manifestations of the disease, regardless of age. Furthermore, it can be concluded that in this study, dogs with BS had frequent laryngeal alterations and that alterations in the main bronchi were present in all animals with severe manifestations of the disease. Keywords: airway obstruction, bronchial collapse, endoscopy, larynx

Risk of arrhythmias in dogs with structural heart disease

ABSTRACT: Presently, pet life expectancy is becoming longer and several diseases inherent to age have been diagnosed, with heart disease being a frequent finding. Although various heart diseases have different pathophysiologies, many morphological and hemodynamic changes can predispose patients to arrhythmias. The presence of arrhythmias can worsen the underlying heart disease and predispose patients to develop new alterations, making arrhythmia detection important for establishing adequate therapeutic protocols and a better prognosis. The present study aimed to determine the arrhythmias most frequently found in dogs treated at the Cardiology and Respiratory Diseases Service (SCDR) of the Small Animals Sector of the Veterinary Hospital of the Federal Rural University of Rio de Janeiro (UFRRJ), during the period from January to 2014 to December 2017, relating them to sex, age group, size, and the presence or absence of heart disease. A total of 586 medical records of dogs treated with SCDR-UFRRJ were retrospectively evaluated. Of these, 15.4% had arrhythmias, 95.6% had diagnoses of heart disease, 61.1% (55/90) were diagnosed with mitral valve disease, and 27.8% (25/90) had dilated cardiomyopathies. The most frequent rhythm disturbances were premature ventricular complexes associated with chronic degenerative mitral valve disease or dilated cardiomyopathy. Statistical analysis confirmed the risk of a cardiac patient developing rhythm or conduction alterations (OR, 4.46; p = 0.0003). In conclusion, the pathophysiology of heart failure can lead to the development of rhythm and conduction disorders

Comparative study of the clinical and echodopplercardiographic aspects of left ventricular hypertrophy and hypertrophic cardiomyopathy in cats (Felis catus).

The aim of the present study was to differentiate hypertrophic cardiomyopathy (HCM) from concentric left ventricular hypertrophy (CLVH) and to compare their echodopplercardiography measurements in random bred domestic cats. After owners consent cats of any sex or age with no history of heart disease were randomly submitted to physical examination and echocardiogram. When left ventricular hypertrophy was present on the echocardiogram, cats were further examined by chest X-rays, ultrasonography and laboratory work. Those presenting cardiac hypertrophy with the diagnosis of any disease that could cause left ventricular hypertrophy were allocated into one group (CLVH) and those presenting hypertrophy without any concomitant detectable disease were allocated to another group (HCM). Cats with ventricular hypertrophy cats were included (n=10), among which five were classified as secondary CLVH, with hyperthyroidism being the main cause and five characterized as HCM. Considering the diagnosis of concentric ventricular hypertrophy, other diseases should be investigated and ruled out, such as hyperthyroidism. It is also necessary to consider and monitor cardiac changes more closely, since their phenotypic manifestation was severer than those observed in the animals with HCM. However, to determine whether disease progression in these animals is faster severer than in others, further epidemiological studies are necessary

Heat pretreatment of canine samples to evaluate efficacy of imidacloprid + moxidectin and doxycycline in heartworm treatment

Abstract Background Considering the recent information on the increase of Dirofilaria immitis antigen detection by rapid assays in canine blood samples after heat treatment, the proposal that immune complexes block D. immitis antigen detection and that macrocyclic lactone + doxycycline (alternative protocol) might lead to increased production of those immune complexes, resulting in the erroneous diagnosis of adult worm elimination, and that there is no recommended adulticide marketed in Brazil, a study was performed to evaluate the interference of moxidectin + doxycycline (moxi-doxy) on diagnostic procedures when heartworm positive dogs are treated with this alternative protocol. Twenty-two naturally infected pet dogs were treated monthly with topical 10% imidacloprid + 2.5% moxidectin and with oral doxycycline (10 mg/kg BID/30 days) (moxi-doxy). All the dogs had their microfilaremia level determined prior to the first day of treatment, and were tested every 6 months for microfilariae (Mf) detection prior to heating, and for antigen detection prior to and after heating, the sample. Results The results indicate that the treatment protocol can eliminate adult heartworms as early as 6 months after the first dose, especially in low microfilaremic dogs (< 300 Mf/ml). In this study, all dogs were free of heartworm antigen after 18–24 months of treatment. In a comparison of pre-heated samples and non-heated samples, sample pre-heating increased antigen detection sensitivity, and non-heated samples tended to be antigen-negative earlier than the pre-heated samples, especially when dogs had low microfilaremia levels. These discrepancies were not present in a subsequent sample of the same dog 6 months later. Conclusions Two negative antigen test results 6 months apart can be recommended as the criterion to consider when a dog has been cleared of infection. The initial microfilaremia level of a dog can be used to estimate the necessary time frame to end the treatment period

Clinical and blood count findings in dogs naturally infected with Dirofilaria immitis

Dirofilaria immitis is a nematode that infects canids worldwide as well as other mammalian species, including humans. Worms and dogs are well adapted to one another, making dogs the best urban host for the parasite. Nevertheless, 30% of dogs do not sufficiently present microfilaremia, that is, the low larval load impairs transmission by mosquitoes and diagnosis by its detection in the blood samples. Therefore, the canine diagnosis must always include a microfilaria test and serological tests to detect adult worm antigens. To describe the clinical findings in naturally infected dogs in Rio de Janeiro, 34 dogs were included in the study. All dogs were evaluated for history, anamnesis, physical examination, complete blood count (CBC), D. immitis testing for antigens (ELISA test SNAP 4Dx Plus®), and microfilarial burden. The most frequent complaint from the owners was coughing (14.7%, 5/34). The most common CBC finding was eosinophilia (29.4%), followed by thrombocytopenia (26.5%) and neutrophilia (14.7%). Of the 34 animals, 91.2% were microfilaremic, with a mean count of 11.939 microfilaria/mL. Veterinarians working in areas endemic to D. immitis should always undergo screening tests and pulmonary auscultation, and increased expiratory sounds, even in the absence of coughing, can be considered a sign of the disease, along with eosinophilia, thrombocytopenia, and neutrophilia