Platynosomum illiciens infection in domestic cats: insights from a sanctuary.

Platynosomum illiciens, a trematode parasite known for its intricate life cycle, predominantly infests the liver, gallbladder, and bile ducts of domestic cats. In this study, we examined feline fecal samples from a cat sanctuary in Metropolitan Rio de Janeiro, Brazil, aiming to determine whether, even in such environments, cats retain their atavistic hunting habits, as evidenced by the presence of P. illiciens in fecal samples. The infection diagnosis utilized centrifugal sedimentation in the formalin-ethyl acetate test. Out of 72 fecal samples collected from various cats, four tested positive for P. illiciens eggs. This study serves as a reminder that even in environments where they are well-fed, cats exhibit predatory behavior, engaging in hunting and consuming prey, thus exposing themselves to parasites. It emphasizes the importance of veterinarians and cat caretakers being cognizant of the widespread presence of P. illiciens in Brazil and considering it in the differential diagnosis for cats presenting with liver or gallbladder issues. In conclusion, our findings underscore that the ancestral instinct for hunting and predation, preserved in domestic cats, persists despite fulfilling their nutritional needs.

Platynosomum illiciens, um parasito trematódeo conhecido por seu ciclo de vida complexo, infesta predominantemente o fígado, a vesícula biliar e os ductos biliares de gatos domésticos. Neste estudo, examinamos amostras fecais de felinos de um santuário de gatos na região metropolitana do Rio de Janeiro, Brasil, com o objetivo de determinar se, mesmo nesses ambientes, os gatos mantêm seus hábitos de caça, evidenciado pela presença de P. illiciens em amostras fecais. O diagnóstico da infecção foi realizado por sedimentação centrífuga no teste de formalina-acetato de etila. Foram obtidas 72 amostras fecais de diferentes gatos e quatro testaram positivo para ovos de P. illiciens. Este estudo é um lembrete de que os gatos terão comportamento predatório, caçando e consumindo presas mesmo quando bem alimentados, ficando expostos ao parasito. Veterinários e cuidadores de gatos devem estar atentos à ampla presença de P. illiciens no Brasil e considerá-la no diagnóstico diferencial de gatos com problemas de fígado ou vesícula biliar. Concluindo, nossos resultados mostram que o instinto atávico dos gatos que se mantiveram conservados durante a domesticação não pode ser anulado quando as necessidades nutricionais dos gatos são satisfeitas.

Dogs infected by Dirofilaria immitis: a threat to the health of human and non-human animals in Rio de Janeiro, Brazil.

This study aimed to investigate the presence of Dirofilaria immitis microfilaremia in dogs from two regions of the state of Rio de Janeiro, Brazil, where heartworm infections are highly prevalent. Blood samples were collected from dogs aged > 12 months, independent of the use of preventatives. All samples obtained and analyzed using Knott's modified test by the investigators. A total of 133 blood samples were tested, and D. immitis microfilariae were detected in 29 of them, resulting in an occurrence of 21.8%. The percentage of dogs with microfilaremia detected raises concerns for pet families, one health professionals, and small animal practitioners. Microfilaremic dogs are the richest source of infection for the mosquitoes, increasing the risk of transmission. Therefore, the stakeholders in One Health must raise concerns regarding the health of wild animals, as wild canids and other species of wild animals are exposed to the risk of D. immitis infection. In addition, humans can get infected and develop human pulmonary dirofilariasis. In conclusion, the presence of dogs with microfilaremia potentiates opportunities for D. immitis transmission, exposing all animals, wild or domestic, human or non-human to the disease.

Este estudo objetivou investigar a presença de cães portadores de microfilemia da espécie Dirofilaria immitis em duas áreas do estado do Rio de Janeiro, Brasil onde a infecções por vermes do coração são altamente prevalescentes. Amostras de sangue foram obtidas de cães com mais de 12 meses de idade, independentemente do uso de preventivos. Todas as amostras foram obtidas e analisadas pelo grupo do estudo utilizando-se o teste de Knott modificado. Um total de 133 amostras foi testado e microfilárias de D. immitis foram detectadas em 29 amostras, resultando em uma ocorrencia de 21,8%. A porcentagem de cães com microfilaremia detectada gera preocupações para as famílias de animais de estimação, para profissionais da saúde única e para clínicos de pequenos animais. Cães microfilarêmicos são a mais rica fonte de infecção para mosquitos, aumentando o perigo de transmissão. Assim, atores de todos os segmentos sociais com interesse na saúde única devem incluir a saude de animais selvagens em suas preocupações, uma vez que canideos selvagens e outras espécies de animais selvagens são expostos ao desafio da infecção por D.immitis. Além disso, seres humanos podem se tornar infectados e desevolver dirofilariose pulmonar humana. Em conclusão, a presença de cães microfilarêmicos potencializa as oportunidades de trasmissão de D. immitis, expondo todos os animais, selvagens ou domesticos, humanos ou não humanos à doença.

How does Dirofilaria immitis infection impact the health of dogs referred to cardiology care.

Dirofilaria immitis is a nematode that can cause a disease that may present clinical signs from severe to absent. When dogs are symptomatic, the clinical signs are cardiorespiratory and nonspecific, which may be misleading. This study aimed to demonstrate the clinical presentations to cardiac care by evaluating 26 dogs subjected to clinical examination, complete blood count (CBC), specific tests for D. immitis infection, chest radiography, and echocardiography. Among them, 11 (42.3%) dogs were infected and 15 (57.7%) were non-infected. Most dogs presented with coughing (65.4%) and abnormal lung sounds (81%) independent of infection. Murmur at the tricuspid focus was present in 26.9% of the dogs, of which 57.1% were infected. Echocardiography revealed tricuspid regurgitation in 30.8% of the dogs and pulmonary regurgitation in 46.1%, of which 37.5% and 50% were infected, respectively. Worms were detected by echocardiography in 45.5% of the infected dogs. The x-rays showed that the bronchial pattern was present in 45.5% of the infected dogs and in 46.7% of the non-infected dogs. The interstitial pattern was present in 18.2% of the infected animals, in contrast to 6.7% of the non-infected dogs. The CBC results for all dogs were within the reference range, except for platelets. Although similar, the percentage of dogs with thrombocytopenia was higher among infected dogs (36.4%) than among the non-infected (6.7%). These results reinforce that due to the non-specific signs of infection, it is mandatory to perform parasitological assays when evaluating dogs presenting with cardiopulmonary signs.

Dirofilaria immitis, é um nematoide que pode causar sinais clínicos de graves a ausentes. Quando os cães são sintomáticos, os sinais clínicos são cardiorrespiratórios e inespecíficos, o que pode confundir com outras doenças. Com o objetivo de descrever a apresentação clínica de cães atendidos em um serviço de cardiologia e doenças respiratórias, após consentimento dos tutores, 26 pacientes foram submetidos a exame clínico, hemograma, exames específicos para infecção por D. immitis, radiografia de tórax e ecocardiografia. Entre esses cães, 11 estavam infectados (42,3%) e 15 não infectados (57,7%). A maioria dos cães apresentou tosse (65,4%) e sons pulmonares anormais (81%) independentemente da infecção. O sopro no foco tricúspide estava presente em 26,9% dos cães, sendo 57,1% infectados. A ecocardiografia mostrou insuficiência tricúspide em 30,8% dos cães e insuficiência pulmonar em 46,1%, sendo 37,5% e 50% infectados, respectivamente. Parasitos foram detectados pela ecocardiografia em 45,5% dos cães infectados. As radiografias mostraram que o padrão brônquico estava presente em 45,5% dos cães infectados e em 46,7% dos não infectados. O padrão intersticial esteve presente em 18,2% dos infectados e em 6,7% dos não infectados. Os resultados do hemograma de todos os cães estavam dentro do intervalo de referência para todas as células, exceto plaquetas. Embora semelhante, a porcentagem de cães com trombocitopenia foi maior entre os cães infectados (36,4%), do que entre os livres de infecção (6,7%). Esses resultados reforçam que, devido aos sinais inespecíficos da infecção, é obrigatória a realização de ensaios parasitológicos na avaliação de cães que apresentem sinais cardiopulmonares.

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.

Dirofilaria immitis, é um nematoide que infecta canídeos em todo o mundo, bem como outras espécies de mamíferos, incluindo humanos. Os vermes e os cães estão bem adaptados um ao outro, tornando os cães o melhor hospedeiro urbano para o parasita. Contudo, 30% dos cães não apresentam microfilaremia, prejudicando a transmissão pelos mosquitos e o diagnóstico por detecção de larvas em amostras de sangue. Portanto, o diagnóstico canino deve incluir sempre a pesquisa de microfilárias e sorologia para detecção do antígeno do verme adulto. Com o objetivo de descrever os achados clínicos de cães naturalmente infectados no Rio de Janeiro, 34 cães foram incluídos. Todos os cães foram avaliados por histórico, anamnese, exame físico, hemograma completo (CBC), teste de antígenos, pesquisa e contagem de microfilárias de D. immitis. A queixa mais frequente dos responsáveis foi a tosse (14,7% - 5/34). O achado de hemograma mais comum foi eosinofilia (29,4%), seguido de trombocitopenia (26,5%) e neutrofilia (14,7%). Dos 34 animais, 91,2% eram microfilarêmicos com contagem média de 11.939 microfilárias/mL. Os veterinários que atuam em áreas endêmicas de D. immitis devem sempre realizar exames de triagem e ausculta pulmonar, pois mesmo na ausência de tosse, sons expiratórios aumentados podem ser considerados um sinal da doença, assim como eosinofilia, trombocitopenia e neutrofilia.

Pulmonary atelectasis in a young dog with Cor pulmonale: clinical and radiographic follow-up.

Pulmonary atelectasis is a disease characterized by the collapse of the pulmonary alveoli, leading to partial or total loss of function in the affected lung, and is mostly described in older dogs. It occurs due to chronic inflammatory and obstructive processes such as pneumonia. In infants who do not feed directly from the mother, it is common to develop aspiration pneumonia due to inhalation of a milk replacer. Once aspirated, food generates an inflammatory process in the airway that alters the function of the pulmonary surfactant, increases mucus production, and causes consequent airway obstruction, which may progress to alveolar and bronchial collapse. The aim of the present study was to report a case of a 4-month-old canine with pulmonary atelectasis secondary to bronchopneumonia and the outcome of the clinical case. The patient presented with cough, exercise intolerance, tachypnea, and progressive weight loss. Thoracic radiographic examination was performed to identify displacement of the mediastinum and heart overlapping the collapsed lung, interstitial-alveolar pattern associated with atelectasis of the middle lobe of the right lung, and a diffuse interstitial bronchial pattern throughout the other lung fields. Pulmonary support treatment was administered with antibiotics, bronchodilators, mucolytics, and inhaled corticosteroids, with resolution of clinical and radiographic symptoms after 60 days of treatment. Therefore, adequate treatment of chronic bronchopneumonia is effective in resolving pulmonary atelectasis and its associated clinical complications.

A atelectasia pulmonar é uma enfermidade caracterizada pelo colapso dos alvéolos pulmonares levando a perda de função parcial ou total do pulmão acometido, sendo mais frequente em cães mais velhos. Ocorre devido a processos inflamatórios crônicos e obstrutivos como as pneumonias. Em filhotes que não se alimentam diretamente da mãe, é comum o desenvolvimento de pneumonia aspirativa devido à inalação de fórmula de leite. Uma vez broncoaspirado, o alimento gera um processo inflamatório que altera a função do surfactante pulmonar, aumento na produção de muco e consequente obstrução das vias aéreas, podendo progredir para colapso de alvéolos e brônquios. O objetivo do presente estudo foi relatar um caso de um canino, de 4 meses de idade, com atelectasia pulmonar secundária a broncopneumonia e a evolução do caso clínico. O paciente apresentava sinais de tosse, intolerância a exercícios, taquipneia e emagrecimento progressivo. Realizado exame radiográfico de tórax, identificou-se deslocamento de coração sobrepondo-se ao pulmão colapsado, padrão interstício-alveolar associado a atelectasia do lobo médio do pulmão direito, além de padrão intersticial brônquico difuso pelos demais campos pulmonares. O tratamento de suporte pulmonar foi realizado com antibióticos, broncodilatadores, mucolíticos e corticosteroides inalatórios, com resolução dos sintomas clínicos e radiográficos após 60 dias de tratamento. Portanto, o tratamento adequado para broncopneumonia crônica foi eficaz na resolução da atelectasia pulmonar e suas complicações clínicas.

Feline Heartworm in Clinical Settings in a High Canine Prevalence Area.

Heartworm (HTW) infection in cats is associated with persistent pulmonary pathology, even when clinical signs are absent. Treatment options for cats are limited once infected, making prevention an important topic for discussion with cat owners. In Brazil, tests to detect feline HTW infections are unavailable, likely leading to an underestimation of its impact on the wellbeing of cats. The present study investigated the seroprevalence of HTW antigen in cats living in an area with high canine HTW prevalence and investigated risk factors and clinical signs associated with HTW disease in cats from Rio de Janeiro, Brazil. Clinical examinations were conducted, and serological evaluations performed with a point-of-care test (SNAP® Feline Triple® Test, IDEXX Laboratories, Inc.). A total of 586 cats were examined. The HTW antigen seroprevalence was 1.2%. Heartworm positive results were significantly associated with vomiting and abnormal lung sounds. Results from this study indicate that cats residing in areas of high canine HTW prevalence should have HTW disease as a differential diagnosis when presenting with compatible clinical signs. Veterinarians should prioritize client education and promote regular use of effective prophylaxis to protect feline health.

Efficacy of semi-annual therapy of an extended-release injectable moxidectin suspension and oral doxycycline in Dirofilaria immitis naturally infected dogs.

BACKGROUND: Dirofilaria immitis is a life-threatening nematode spreading globally. Arsenical treatment is currently recommended for removal of adult worms. However, arsenical treatment is not available in some countries, and there are dogs that cannot tolerate the rapid kill of adult worms; therefore, alternative adulticide slow-kill treatments are needed. Criticisms against the use of these alternative protocols include the potential for allowing disease to progress and for the development of ML-resistant worms. METHODS: The efficacy of a protocol that includes semi-annual doses (i.e. every 6 months) of commercially available extended-release injectable moxidectin suspension (ProHeart® SR-12) with 30-day oral administration of doxycycline was studied in 20 dogs with naturally occurring D. immitis infections. Each dog received treatment with ProHeart® SR-12 (0.5 mg moxidectin/kg) by subcutaneous injection and oral doxycycline (10 mg/kg/bid × 30 days) every 6 months until two consecutive negative antigen test results were obtained. Pulmonary and cardiac evaluations were performed by radiographic and echocardiographic parameters. Physical examinations, complete blood counts, clinical chemistry profiles, microfilariae and antigen tests were performed periodically. RESULTS: At enrollment, all dogs were positive for D. immitis antigen and 18 were microfilaremic. On day 30, microfilaremia counts decreased, and all dogs became amicrofilaremic by day 150. On day 180, 11 dogs were antigen-negative, and 7 more became negative by day 360. The two remaining antigen-positive dogs converted to negative by day 540 or 810. All antigen tests performed 180 days after the first negative test were negative. There was no decline in cardiac performance of the dogs throughout the study. Overall, pulmonary clinical conditions, presence of worms by echocardiography, and enlargement of caudal and main pulmonary arteries improved after treatment. Physical examinations, complete blood count results, and clinical chemistry profiles were within normal reference values. Respiratory conditions were improved, no damage to the heart was observed, and the treatment protocol was well tolerated by the animals. CONCLUSIONS: This alternative adulticide treatment was efficacious and well tolerated in naturally infected dogs. The injectable formulation provides the advantage of having veterinarians able to administer, monitor, and assess the efficacy and condition of the dog throughout the treatment and post-treatment periods.

Unusual feline Dirofilaria immitis infection: a case report.

Cats are less susceptible to Dirofilaria immitis infection than dogs. Although rare, the feline disease can be fatal even with low parasitic loads. The infection is often asymptomatic or has non-specific symptoms that are mainly associated with the death of immature worms. Microfilaremia is rare and transient. Normally, microfilaremia, when present, lasts for not more than 33 days. This study describes a feline case presenting with non-specific clinical signs and prolonged microfilaremia. Case: a random bred cat infected by feline leukemia virus (FeLV) that was found to be microfilaremic by chance. The infection was detected by the presence of microfilariae in a blood smear and was confirmed by antigen test (SNAP Feline Triple Test, Idexx®) and echocardiogram.

Use of Slow-Release Injectable Moxidectin for Treatment of Dirofilaria immitis Infection During Pregnancy.

Canine heartworm disease is a life-threatening disease caused by Dirofilaria immitis and is prevalent in Brazil. The standard drug for its treatment, melarsomine dihydrochloride, is a fast-killing organic arsenical chemotherapeutic agent not approved in Brazil. Therefore, an alternative strategy, such as macrocyclic lactone in combination with a tetracycline antibiotic, has to be used. The alternative method is a long-term therapy that could lead to compliance issues during treatment. The aim of this case report is to present a preliminary assessment on the efficacy and safety of an off-label biannual administration of slow-release moxidectin (0.5 mg/kg every 6 months), which is formulated for annual administration (0.5 mg/kg annually). This overdose was chosen to test if moxidectin serum levels could be maintained high enough to harm the worms. It was administered to a 4-year-old female dog in combination with a 30-day doxycycline course. The second dose of moxidectin was administered approximately a week before she gave birth to three healthy puppies. Microfilariae were not detected on day 180 of treatment. Serological tests showed that the worms were eliminated, as two negative antigen tests were obtained 6 months apart (at day 180 and day 360 of treatment). Therefore, the off-label biannual use of moxidectin in combination with doxycycline was effective in eliminating D. immitis in 360 days and was harmless for the pregnant dog and her offspring, suggesting that this strategy is promising. Although these results are encouraging, further studies are needed to confirm safety and efficacy issues.