Social media as a tool for detecting underdiagnosed parasitic infections: the case of spirocercosis.

Spirocercosis is a parasitic disease caused by the nematode Spirocerca lupi that affects several canids around the world. In Costa Rica, few spirocercosis cases have been reported; however, it is suspected that the infection is currently underdiagnosed. As seen during the COVID-19 pandemic, social media has sped up the spread of scientific knowledge, raising practioner's awareness of the epidemiology and signs and manifestations of infections. The aim of this work was to use social media as a tool for increasing awareness of spirocercosis among veterinarians and investigate the frequency of cases occurring in Costa Rica. Infographic material about the infection was disseminated by Whatsapp, Facebook, and Instagram from January 2021 to July 2022 using a public account of the Laboratory of Helminthology of the University of Costa Rica. In addition, Google Forms questionnaires were completed by veterinarians to report the number of spirocercosis cases in their clinics, associated manifestations, diagnosis, treatment, and outcome of the disease. Remarkably, since 2020, a six-fold increase in the number of cases per year was noted. Clinical manifestations matched those reported elsewhere, and one of every three dogs infected with S. lupi died spontaneously or required euthanasia because of the infection. This work suggests that S. lupi infection in Costa Rica may have been underdiagnosed in the last decade, and the knowledge and awareness of clinical personnel play a major role in the detection of this and other infectious diseases.

Subcutaneous spirocercosis in a dog from Costa Rica and first molecular confirmation of Spirocerca lupi in Central America.

Spirocerca lupi is the etiological agent of spirocercosis in canids from tropics and subtropics in the world. This parasite can lead to life threatening complications, including the formation of fibro and osteosarcomas. A 5-year-old crossbreed Maltese dog from Costa Rica was presented to a veterinary clinic with two nodules in the subcutaneous tissues of the cervical region. One of the nodules resolved with intramuscular antibiotic and anti-inflammatory treatment. However, the other nodule persisted and became purulent. The content of the nodule was excised releasing two coiled 3-cm reddish worms. Identity of the specimens was confirmed by amplifying an 850 bp fragment of the 18S rDNA. The obtained sequence showed 99.96% similarities with S. lupi from Hungary. The present study highlights the need of veterinary clinicians' awareness towards nematode aberrant migrations, and the require of molecular studies to gain insight into the parasite's evolutionary history.

Massa esofágica em cárdia de um cão / Esophageal mass in cardia of a dog

O sistema digestório é responsável pela quebra dos alimentos em menores partes, a fim de gerar energia, crescimento e renovação celular. É constituído de um tubo digestivo formado por boca, esôfago, estômago, alças intestinais, reto e ânus; além dos órgãos anexos. O esôfago dá continuidade ao canal alimentar da faringe ao estômago. O câncer de esôfago, em cães e gatos, ocorre raramente, representando cerca de menos de 0,5% de todos os tumores nessas espécies. O maior fator de risco para os tumores esofágicos em cães está relacionado com as áreas endêmicas do nematódeo Spirocerca lupi, que parasita o cão. Diante do exposto, neste trabalho, relata-se o caso de um cão da raça Pit Bull, com dez meses de idade, que deu entrada no Hospital Veterinário Prof. Mário Dias Teixeira com histórico de apatia, tosse, engasgo e alotriofagia. Foram solicitados exames de hemograma, bioquímica sérica, PCR, radiografia, ultrassonografia e endoscopia digestiva alta. Os exames hematológicos indicaram alterações sistêmicas e os exames de imagem apontaram alterações no trato gastrointestinal, sendo que o exame endoscópico apontou a presença de uma massa em região ventral da mucosa esofágica.

The digestive system is responsible for breaking food into smaller pieces to generate energy, growth, and cell renewal. It consists of a digestive tube formed by mouth, esophagus, stomach, intestinal loops, rectum, and anus, as well as attached organs. The esophagus continues the alimentary canal from the pharynx to the stomach. Esophageal cancer in dogs and cats is rare, accounting for less than 0.5% of all tumors in these species. The major risk factor for esophageal tumors in dogs is related to endemic areas of the nematode Spirocerca lupi that parasitizes the dog. This work presents the case of a 10-month-old Pit Bull dog that was admitted at the Veterinary Hospital Prof. Mário Dias Teixeira with a history of apathy, cough, choking, and allotriophagia. Hemogram, serum biochemistry tests, PCR, radiography, ultrasonography, and upper digestive endoscopy were requested. The hematological exams indicated systemic alterations and the imaging exams presented alterations in the gastrointestinal tract, while the endoscopic exam showed the presence of a mass in the ventral region of the esophageal mucosa.

Spirocerca lupi Proteomics and Its Role in Cancer Development: An Overview of Spirocercosis-Induced Sarcomas and Revision of Helminth-Induced Carcinomas.

Spirocerca lupi is a parasitic nematode of canids that induces a myriad of clinical manifestations in its host and, in 25% of infections, leads to the formation of sarcomas. The description of the protein composition of the excretory and secretory products (Sl-ESP) of S. lupi has shed light on its possible interactions with the host environment, including migration within the host and mechanisms of immunomodulation. Despite this, the process by which S. lupi induces cancer in the dog remains poorly understood, and some hypotheses have arisen regarding these possible mechanisms. In this review, we discuss the role of specific ESP from the carcinogenic helminths Clonorchis sinensis, Opisthorchis viverrini and Schistosoma haematobium in inducing chronic inflammation and cancer in their host's tissues. The parasitic worms Taenia solium, Echinococcus granulosus, Heterakis gallinarum, Trichuris muris and Strongyloides stercoralis, which have less-characterized mechanisms of cancer induction, are also analyzed. Based on the pathological findings in spirocercosis and the mechanisms by which other parasitic helminths induce cancer, we propose that the sustained inflammatory response in the dog´s tissues produced in response to the release of Sl-ESP homologous to those of other carcinogenic worms may lead to the malignant process in infected dogs.

Spirocerca lupi (Spirurida: Spirocercidae) infection associated to secondary megaesophagus and obstructive process in a senile dog / Infecção por Spirocerca lupi (Spirurida: Spirocercidae) associada a megaesôfago secundário e processo obstrutivo em um cão senil

Spirocerca lupi is a nematode parasite that can be found in the esophagus and aorta of carnivores, including humans. Affected animals may develop mild to severe lesions, depending on the degree of infection, route of larval migration and the inflammatory response. The present work describes the occurrence of S. lupi in a 16-year old male Chow Chow dog, presenting a chronic esophagus infection, associated with a critical obstruction. After the identification of the parasite egg by faecal exam, the patient was treated with milbemycin in combination with praziquantel P.O., in days zero, seven and 28 after the diagnose. An esophagogram was also performed, confirming the secondary megaesophagus. The team of clinicians decide to perform a euthanasia due to the complication of the patient"s condition, even after the anthelmintic treatment. This report is important as it describes a case after 18 years of epidemiological silence in the Metropolitan region of Curitiba, PR, Brazil. The present data aims to raise awareness about the prevalence of this zoonotic disease and the importance of a specific clinical and radiographic diagnose in dogs. It is noteworthy to report the difficulty to reduce the size of the associated esophagus mass even after a potent anthelmintic treatment.(AU)

Spirocerca lupi é um parasito nematoide que pode ser encontrado no esôfago e na aorta de carnívoros, incluindo humanos. Os animais afetados pela doença podem desenvolver de lesões leves a graves, dependendo do grau de infecção, migração larval e resposta inflamatória. O presente trabalho descreve a ocorrência do parasito em um cão Chow Chow de 16 anos de idade, com infecção crônica, apresentando megaesôfago secundário associado a uma crítica obstrução do órgão. Após a identificação do ovo do parasito, foi realizado tratamento antiparasitário oral com a combinação de milbemicina e praziquantel, nos dias zero, sete e 28 após o diagnóstico. Também foi realizado esofagograma, confirmando o megaesôfago secundário. A equipe médica decidiu pela eutanásia do cão devido a sua complicação da condição clínica quando o paciente retornou, mesmo após o tratamento com anti-helmíntico. Este relato é importante porque descreve um caso após 18 anos de silêncio epidemiológico na região metropolitana de Curitiba, Paraná, Brasil. Os presentes dados visam conscientizar sobre a prevalência dessa doença zoonótica e a importância de um diagnóstico clínico e radiográfico específico em cães. É digno de nota relatar a dificuldade em reduzir o tamanho da massa esofágica associada, mesmo após um tratamento anti-helmíntico potente.(AU)

Spirocerca lupi (Spirurida: Spirocercidae) infection associated to secondary megaesophagus and obstructive process in a senile dog / Infecção por Spirocerca lupi (Spirurida: Spirocercidae) associada a megaesôfago secundário e processo obstrutivo em um cão senil

Spirocerca lupi is a nematode parasite that can be found in the esophagus and aorta of carnivores, including humans. Affected animals may develop mild to severe lesions, depending on the degree of infection, route of larval migration and the inflammatory response. The present work describes the occurrence of S. lupi in a 16-year old male Chow Chow dog, presenting a chronic esophagus infection, associated with a critical obstruction. After the identification of the parasite egg by faecal exam, the patient was treated with milbemycin in combination with praziquantel P.O., in days zero, seven and 28 after the diagnose. An esophagogram was also performed, confirming the secondary megaesophagus. The team of clinicians decide to perform a euthanasia due to the complication of the patient"s condition, even after the anthelmintic treatment. This report is important as it describes a case after 18 years of epidemiological silence in the Metropolitan region of Curitiba, PR, Brazil. The present data aims to raise awareness about the prevalence of this zoonotic disease and the importance of a specific clinical and radiographic diagnose in dogs. It is noteworthy to report the difficulty to reduce the size of the associated esophagus mass even after a potent anthelmintic treatment.

Spirocerca lupi é um parasito nematoide que pode ser encontrado no esôfago e na aorta de carnívoros, incluindo humanos. Os animais afetados pela doença podem desenvolver de lesões leves a graves, dependendo do grau de infecção, migração larval e resposta inflamatória. O presente trabalho descreve a ocorrência do parasito em um cão Chow Chow de 16 anos de idade, com infecção crônica, apresentando megaesôfago secundário associado a uma crítica obstrução do órgão. Após a identificação do ovo do parasito, foi realizado tratamento antiparasitário oral com a combinação de milbemicina e praziquantel, nos dias zero, sete e 28 após o diagnóstico. Também foi realizado esofagograma, confirmando o megaesôfago secundário. A equipe médica decidiu pela eutanásia do cão devido a sua complicação da condição clínica quando o paciente retornou, mesmo após o tratamento com anti-helmíntico. Este relato é importante porque descreve um caso após 18 anos de silêncio epidemiológico na região metropolitana de Curitiba, Paraná, Brasil. Os presentes dados visam conscientizar sobre a prevalência dessa doença zoonótica e a importância de um diagnóstico clínico e radiográfico específico em cães. É digno de nota relatar a dificuldade em reduzir o tamanho da massa esofágica associada, mesmo após um tratamento anti-helmíntico potente.

Spirocerca lupi: aspectos gerais do parasito e da espirocercose em cães / Spirocerca lupi: general aspects of parasite and spirocercosis in dogs

O nematódeo Spirocerca lupi, causador da espirocercose, é um parasito que acometeprincipalmente cães e canídeos silvestres. Seu ciclo biológico envolve hospedeirosintermediários, os besouros coprófagos e pequenas aves, répteis e roedores que servem como hospedeiros paratênicos. A doença é de ocorrência cosmopolita, com maior prevalência em países tropicais e subtropicais, sendo endêmica na África do Sul. Também já foi relatada em alguns países da América do Sul, incluindo o Brasil, sendo mais prevalente em cães de caça e cães errantes. Os vermes adultos parasitam esôfago, estômago e artéria aorta dos hospedeiros definitivos, provocando nódulos, granulomas e diversas lesões. A sintomatologia da espirocercose varia de acordo com o processo migratório do parasito no organismo do animal, os órgãos afetados, bem como a evolução da doença. Sintomas como a regurgitação, a emese, a disfagia e a perda de peso, são as principais manifestações clínicas observadas em cães parasitados. O diagnóstico se baseia nos achados clínicos, exames de imagem, parasitológico de fezes ou das secreções daregugitação, emese e achados de necropsia. O tratamento pode ser clínico, ainda poucoviável, ou cirúrgico para remoção dos nódulos contendo os parasitos. Como medidas preventivas a literatura cita evitar o acesso de cães aos hospedeiros paratênicos e, além disso, eles não devem ser alimentados com vísceras cruas de outros animais domésticos e silvestres.(AU)

The nematode Spirocerca lupi, which causes spirocercosis, is a parasite that mainly affects dogs and wild canids. Its biological cycle involves intermediate hosts, the coprophagous beetles and small birds, reptiles and rodents that serve as paratenic hosts. The disease is of cosmopolitan occurrence with a higher prevalence in tropical and subtropical countries, being endemic in South Africa. It has also been reported in some South American countries, including Brazil, being more prevalent in hunting dogs and stray dogs. The adult worms parasite the esophagus, stomach and aorta artery of the definitive hosts, causing nodules, granulomas and several lesions. The symptoms of spirocercosis varies according to the migratory process of the parasite in the animal organism, the affected organs, as well as the evolution of the disease. Symptoms such regurgitation, dysphagia and weight loss are the main clinical manifestations observed in parasitized dogs. The diagnosis is based on clinical findings, imaging, parasitological examination of feces or secretions of the regurgitation, emese and necropsy findings. The treatment can be clinical, still little viable, or surgical for removal of the nodules containing the parasites. As preventive measures theliterature cites avoiding access of dogs to paratenic hosts and, in addition, they should not be fed with raw viscera of other domestic and wild animals.(AU)

Spirocerca lupi: aspectos gerais do parasito e da espirocercose em cães / Spirocerca lupi: general aspects of parasite and spirocercosis in dogs

O nematódeo Spirocerca lupi, causador da espirocercose, é um parasito que acometeprincipalmente cães e canídeos silvestres. Seu ciclo biológico envolve hospedeirosintermediários, os besouros coprófagos e pequenas aves, répteis e roedores que servem como hospedeiros paratênicos. A doença é de ocorrência cosmopolita, com maior prevalência em países tropicais e subtropicais, sendo endêmica na África do Sul. Também já foi relatada em alguns países da América do Sul, incluindo o Brasil, sendo mais prevalente em cães de caça e cães errantes. Os vermes adultos parasitam esôfago, estômago e artéria aorta dos hospedeiros definitivos, provocando nódulos, granulomas e diversas lesões. A sintomatologia da espirocercose varia de acordo com o processo migratório do parasito no organismo do animal, os órgãos afetados, bem como a evolução da doença. Sintomas como a regurgitação, a emese, a disfagia e a perda de peso, são as principais manifestações clínicas observadas em cães parasitados. O diagnóstico se baseia nos achados clínicos, exames de imagem, parasitológico de fezes ou das secreções daregugitação, emese e achados de necropsia. O tratamento pode ser clínico, ainda poucoviável, ou cirúrgico para remoção dos nódulos contendo os parasitos. Como medidas preventivas a literatura cita evitar o acesso de cães aos hospedeiros paratênicos e, além disso, eles não devem ser alimentados com vísceras cruas de outros animais domésticos e silvestres.

The nematode Spirocerca lupi, which causes spirocercosis, is a parasite that mainly affects dogs and wild canids. Its biological cycle involves intermediate hosts, the coprophagous beetles and small birds, reptiles and rodents that serve as paratenic hosts. The disease is of cosmopolitan occurrence with a higher prevalence in tropical and subtropical countries, being endemic in South Africa. It has also been reported in some South American countries, including Brazil, being more prevalent in hunting dogs and stray dogs. The adult worms parasite the esophagus, stomach and aorta artery of the definitive hosts, causing nodules, granulomas and several lesions. The symptoms of spirocercosis varies according to the migratory process of the parasite in the animal organism, the affected organs, as well as the evolution of the disease. Symptoms such regurgitation, dysphagia and weight loss are the main clinical manifestations observed in parasitized dogs. The diagnosis is based on clinical findings, imaging, parasitological examination of feces or secretions of the regurgitation, emese and necropsy findings. The treatment can be clinical, still little viable, or surgical for removal of the nodules containing the parasites. As preventive measures theliterature cites avoiding access of dogs to paratenic hosts and, in addition, they should not be fed with raw viscera of other domestic and wild animals.

Morphological and molecular identification of Spirocerca lupi (Nematoda: Spiruridae) found in the Andean fox (Lycalopex culpaeus).

Lesions compatible with spirocercosis were found in the esophagus and aorta of an Andean fox from Cuzco, Peru. The esophageal and aortic lesions were 5.5 and 1.5 cm in diameter, respectively. A total of 12 adult nematodes (6 males and 6 females) were collected from the esophageal lesion, and all were identified as Spirocerca lupi by morphological and molecular methods. Molecular characterization was performed by analyzing two sources of the cox1 gene, and the sequences were compared with previous S. lupi sequences from other work deposited in GenBank. Analysis of the partial cox1 gene from S. lupi (n = 3) showed 2 haplotypes and had 95-99% nucleotide similarity to previously described sequences. Also, molecular analysis showed that S. lupi is a very diverse group, due to the genetic variability of the partial sequences of the cox1 gene of Spirocerca. This study is the first to report finding of spirocercosis in the Andean fox.