Histopathological, morphological, and molecular characterization of fish-borne zoonotic parasite Eustrongylides Excisus infecting Northern pike (Esox lucius) in Iran.

Eustrongylides excisus is a fish-borne zoonotic parasite known to infect various fish species, including Northern pike (Esox Lucius). This nematode, belonging to the family Dioctophymatidae, has a complex life cycle involving multiple hosts. This study aimed to investigate the occurrence of Eustrongylides nematodes in Northern pike (E. Lucius) collected from Mijran Dam (Ramsar, Iran). Between June and October 2023, an investigation was conducted on Northern pike from Mijran Dam in Ramsar, Iran, following reports of reddish parasites in their muscle tissues. Sixty fish were examined at the University of Tehran, revealing live parasites in the muscles, which were then analyzed microscopically and preserved for a multidisciplinary study. The skeletal muscle tissues of 85% (51/60) of fish specimens were infected by grossly visible larvae which were microscopically identified as Eustrongylides spp. In histopathological examination, the lesion was composed of encapsulated parasitic granulomatous myositis. Microscopically, the cystic parasitic granulomas compressed the adjacent muscle fibers, leading to their atrophy and Zenker's necrosis. Moreover, epithelioid macrophages, giant cells and mononuclear inflammatory cells were present around the larvae and between the muscle fibers. Finally, a molecular analysis by examining the ITS gene region, revealed that they belong to the species E. excisus. Eustrongylidiasis in northern Iran necessitates further research into the biology, epidemiology, and control of Eustrongylides nematodes, focusing on various hosts. This study is the first to comprehensively characterize E. excisus in Northern pike in Ramsar, Iran, raising concerns about possible zoonotic transmission.

Ancient parasites from endemic deer from "CUEVA PARQUE DIANA" archeological site, Patagonia, Argentina.

The narrow Andean-Patagonian temperate rainforest strip in the west of southern South America is inhabited by two endemic species of cervids, the southern pudu (Pudu puda) and the huemul (Hippocamelus bisulcus), both cataloged as near threatened and threatened species, respectively. One of the possible causes of their declined number is the susceptibility to livestock diseases. Significant zooarchaeological records of both deer have been found throughout the Holocene from Patagonia. The present contribution reports the first paleoparasitological results obtained from coprolites of endemic deer from the archeological site "Cueva Parque Diana," Neuquén Province, Argentina, and discusses the possible diseases found in ancient times. Thirty-four coprolites were fully processed, rehydrated, homogenized, sieved, subjected to spontaneous sedimentation, and examined by light microscopy. Thirty samples contained parasite remains. The presence of diverse parasitic diseases such as trematodioses, metastrongylosis, trichuriosis, strongylida gastroenteritis, dioctophymosis, and coccidiosis which could cause diseases in deer previous to the arrival of European livestock and the presence of zoonotic diseases in the hunters-gatherers and fishermen are discussed.

Third-stage larvae of the enoplid nematode Dioctophyme renale (Goeze, 1782) in the freshwater turtle Trachemys dorbigni from southern Brazil.

The giant kidney worm Dioctophyme renale is normally found in wild carnivores and domestic dogs, with aquatic oligochaetes acting as intermediate hosts. In the present study a prevalence of 50% of third-stage larvae of D. renale was recorded in 60 specimens of the freshwater turtle Trachemys dorbigni from southern Brazil. Larvae were encysted in muscles, the coelomic cavity and mesentery, the serous lining of the stomach and on the surfaces of the lung, heart, liver, pancreas, spleen and intestines. There are no previous records of reptiles being part of the life cycle of D. renale, although fish and amphibians normally act as paratenic hosts. This is the first report of third-stage D. renale larvae in the freshwater turtle, T. dorbigni.

Helminth infracommunity in a maned wolf, Chrysocyon brachyurus, from the humid Chaco, Argentina.

Parasitism is an important factor in conservation worldwide, especially for endangered species, as it can affect host populations by reducing growth rates, fecundity and affecting nutritional status. The maned wolf Chrysocyon brachyurus, a near-threatened species, is distributed across different habitats from the south Amazonian forest in Brazil to northern Argentina, Paraguay and eastern Bolivia. Most studies on gastrointestinal parasites in wild maned wolves are based on coprological findings, and there is little information about adult parasites and parasite species richness. Therefore, this study aims to expand the knowledge about the helminth infracommunity of a maned wolf, describe adult parasites, and explore parasitic coinfections. We performed a necropsy of an adult individual found road killed in Chaco province, Argentina. We collected adult worms from subcutaneous tissues, from the right ventricle, kidneys, and intestine. The parasites were morphologically identified as Dirofilaria immitis, Dioctophyma renale and Spirometra sp. respectively. To our knowledge, this is the first record for adults of Dirofilaria immitis in maned wolves. Filarioids were located within the heart as well as in subcutaneous tissues with mature females containing uterine microfilariae; this study also adds C. brachyurus as a new host for Spirometra sp. in Argentina. Considering that the three helminths found herein are zoonotic and that the maned wolf is an endangered canid, it is essential provide baseline information to determine the risk factors involved in the transmission and extend the studies to sympatric wild and domestic canids in the area.

Ectopic Dioctophyme renale in the thoracic and abdominal cavities associated with renal parasitism in a dog.

Dioctophymosis is the disease caused by the nematode Dioctophyme renale, normally found parasitizing the right kidney of dogs. The absence of symptoms is frequent in parasitized animals. The surgical procedures are commonly performed to treat this disease. This work describes a case involving a canine with renal and ectopic parasitosis in the abdominal and thoracic regions. A mixed-breed female dog, approximately four months old, was diagnosed by ultrasound as for the presence of D. renale in the right kidney and abdominal and thoracic cavities. The animal underwent exploratory celiotomy, nephrectomy of the parasitized kidney, and transdiaphragmatic thoracotomy to remove the thoracic parasite, with a single abdominal surgical wound and excellent postoperative recovery. Several reports of ectopic parasitosis are found, however, the thoracic finding is unusual, and curative therapeutic transdiaphragmatic thoracotomy for dioctophymosis in dogs has not been previously described.

Abdominal dioctophymosis in a domestic cat from the Peruvian rainforest confirmed morphologically and molecularly.

A case of abdominal dioctophymosis in a domestic cat was found in San Juan Bautista district, the Peruvian rainforest, in the Loreto department of Peru. The pet went to a veterinary clinic for a routine ovariohysterectomy during which a large nematode was found in the abdominal cavity. The nematode was morphologically identified as an adult female of Dioctophyme sp. A few morphological parameters, such as the vagina distance from the anterior part and the egg size, were different than D. renale. Partial sequences of the cytochrome c oxidase subunit I (cox1) and the small subunit 18S ribosomal RNA genes were compared with the references from public sequence database and showed a genetic identifies of 89.25% and 99.65% with D. renale, respectively. This is the first mitochondrial molecular analysis of a Dioctophyme specimen from South America and the results showed up to 12.5% nucleotide sequence variation in cox 1 gene of D. renale.

Giant Red Kidney Worm (Dioctophyma renale) Screening and Treatment Protocol and Aberrant Worm Migration In Dogs From Ontario and Manitoba, Canada.

The life cycle of Dioctophyma renale involves an intermediate host (oligochaete), a paratenic hosts (fish and frogs), and a definitive host (mustelids and canids). Dogs are at risk of infection with D. renale when they consume paratenic hosts infected with the larval form of D. renale. Water containing the oligochaete intermediate host cannot be disregarded as another source of infection. Infections occur mainly in the right kidney, but worms have also been found in the abdominal cavity as well as other organs. Most dogs appear asymptomatic and infections are usually noted as incidental findings on necropsy. Recently, the Ontario Society for the Prevention of Cruelty to Animals (SPCA) and Humane Society conducted transports of dogs located in northern remote communities. In 2016, some female dogs were found to be infected with D. renale upon ovariohysterectomy. In response to this discovery, we developed a screening protocol to screen for D. renale infections. In 2018, a total of 130 intact dogs were transferred from 2 northern communities in the provinces of Ontario and Manitoba. A prevalence of 7.94% (95% confidence interval 3.87-14.11%) was found from dogs from the northern communities. The screening protocol we developed provides a method of screening for dogs that are transported from communities that could be at risk of infection with D. renale.

Ectopic dioctophymosis in a dog - Clinical, diagnostic and pathological challenges of a silent disease.

A 9-month old, female, stray dog was rescued and conducted to a university veterinary hospital. Moderate anemia was observed and abdominal ultrasound revealed pancreatitis. Right kidney was not visualized due to intestinal gas. Urinalysis was normal. Castration was performed three weeks later. Before discharge, abdominal ultrasound was performed for internal sutures examination. A cyst-like structure was present in the right retroperitoneal space with what appeared to be tubular worms inside it, not observed in previous evaluation. An ectopic dioctophymosis diagnosis was made. Two female Dioctophyme renale were surgically removed from the structure. Right kidney was hyperemic but not removed. No sign of peritonitis was observed. The dog recovered well. Laboratory follow-up showed no abnormalities a year after the episode and Doppler ultrasound revealed a mild right nephropathy. This is the first canine ectopic dioctophymosis case with only an abdominal cyst-like structure containing viable nematodes, successfully treated. It represents the rarity and difficulties in diagnosing ectopic dioctophymosis even in enzootic locations, highlighting the importance of ultrasonographic screening for such silent, potentially zoonotic disease.

Dioctophyme renale (Goeze, 1782) in the abdominal cavity of a domestic cat from Brazil.

This study reports a case of parasitism by the giant kidney worm, Dioctophyme renale (Goeze, 1782), in the abdominal cavity of a domestic cat from Brazil. A female adult cat presenting prostration, dehydration, physical debility, pronounced jaundice and ascitis, was taken to the Department of Animal Parasitology of the Veterinary Institute of the Universidade Federal Rural do Rio de Janeiro, Brazil. Clinical signs suggested a case of peritonitis. The cat's clinical condition was grave and death occurred within a few days. During necropsy, a brownish-red nematode, 24.9cm long, was found in the abdominal cavity and was identified as a male adult D. renale. This study reports the first confirmed case of dioctophymatosis in the domestic cat. The parasite's aberrant location in the abdominal cavity suggests that the domestic cat is not a suitable host.

Dioctophyme renale (Nematoda, Dioctophymatidae) infection in the crab-eating fox (Cerdocyon thous) from Brazil.

The purpose of this study is to report the first case of parasitism by the giant kidney worm, Dioctophyme renale (Goeze, 1782), in the crab-eating fox, Cerdocyon thous (Linnaeus, 1766), in Brazil. A debilitated adult male fox was taken to the Screening Center for Wild Animals in Rio de Janero (CETAS/RJ) and eventually died of an unknown cause. During necropsy, a brownish-red nematode, 28.9 cm long, was found in the peritoneal cavity. The worm was identified as a male D. renale. This study reports the first case of dioctophymatosis in the crab-eating fox, enlarging the range of wild definitive host species infected by the giant kidney worm in the Neotropical region.

Eustrongylides sp. (Nematoda, Dioctophymatoidea) parasitizing Hoplias malabaricus (Actinopterygii: Erythrinidae) collected from the state of Rio de Janeiro, Brazil.

Hoplias malabaricus (Characiformes, Erythrinidae), trahira, is a neotropical freshwater fish of economic and public health significance. A total of 45 specimens of H. malabaricus commercialized in the municipality of Magé, state of Rio de Janeiro, Brazil, were acquired between April 2016 and April 2018 to investigate the presence of nematode larvae. Twenty of the fish were found parasitized by 347 fourth-stage nematode larvae identified taxonomically as Eustrongylides sp. using morphological, morphometric and molecular data. The parasitic indices were: prevalence 44.44%, mean intensity 17.35, mean abundance 7.71, and range of infection 2-40. Infection sites were musculature, mesentery, abdominal cavity, and serosa of intestine, stomach and liver. This is the first report of Eustrongylides sp. larvae parasitizing H. malabaricus in the state of Rio de Janeiro.

First description of parasite load and clinicopathological and anatomopathological changes in a dog naturally coinfected with Dioctophyme renale and Leishmania infantum in Brazil.

This article reports the case of a domestic dog naturally coinfected with the nematode Dioctophyme renale and with the protozoan Leishmania infantum. The dog exhibited no clinical signs but had normocytic hypochromic anemia, hyperproteinemia, hyperglobulinemia, hypoalbuminemia, and hematuria. Necropsy revealed eight D. renale specimens in the abdominal cavity and in right kidney whose parenchyma was atrophied. Histopathological analysis showed glomerular atrophy, fibrosis and a marked diffuse pyogranulomatous inflammatory infiltrate in the right kidney. Moderate multifocal granulomatous peritonitis was observed in the greater omentum. Several Dioctophyme renale eggs were present amidst the inflammatory infiltrate of the right kidney and greater omentum. Leishmania infantum parasites were detected in perirenal adipose tissue of the right kidney, greater omentum, spleen, bone marrow, and popliteal lymph node. The high D. renale load and the severe and uncommon histological alterations associated with the eggs of this parasite may have been influenced by coinfection with L. infantum.

Dioctophyme renale in a domestic cat (Felis catus): Renal location and nephrectomy.

Dioctophymosis is caused by Dioctophyme renale, nematode with indirect life cycle. Its intermediate host is a freshwater oligochaete and its definitive host is a wild or household carnivore. The adult nematode develops in the definite host, generally locating itself in the kidney. This article was meant to describe the first nephrectomy performed in a domestic cat due to renal dioctophymosis in Argentina. The subject showed a non-specific appearance of generally feeling ill, hematuria and mild diarrhea. It was diagnosed through abdominal ultrasound, followed by exploratory celiotomy and nephrectomy. After verifying absence of free specimens, the right kidney was removed. This organ was found to be enlarged in a spheroidal manner in contrast to the left kidney, with significant thickening of the renal capsule, excessive congestion of vessels and adhesions involving the caudal vena cava. An adult nematode was removed from the right kidney and identified as Dioctophyme renale. Reports of feline dioctophymosis are scarce being most of them necropsy findings. In this we are presenting a confirmed case of D. renale removed by surgery from a live cat. The results presented here reinforces the fact that cats are also appropriate definitive hosts for this parasite.

A human case of Dioctophyma renale (giant kidney worm) accompanied by renal cancer and a retrospective study of dioctophymiasis.

Due to the rarity of human cases and the nonspecific clinical symptoms of dioctophymiasis, Dioctophyma renale infection is not well recognized and is easily neglected or misdiagnosed. Recently, we diagnosed a human case of dioctophymiasis accompanied by renal cancer. To enhance the understanding of human dioctophymiasis, this case is presented here, and a retrospective study of this disease was conducted based on relevant papers screened from PubMed and three Chinese databases. In the end, 32 papers describing 37 human cases of dioctophymiasis were assessed. These cases were distributed in ten countries of Asia, Europe, North America and Oceania, with the highest number in China (n = 22). The majority of the cases occurred in adults (91.9%, 34/37) and involved the kidneys (83.8%, 31/37). Ectopic parasitism mainly occurred in subcutaneous tissue (83.3%, 5/6). A proportion of 45.9% (17/37) of individuals had a history of eating raw or undercooked fish or frogs. The main clinical manifestations of human dioctophymiasis were loin pain (59.5%) and hematuria (59.5%). All the cases were diagnosed based on the morphological characteristics of eggs or adults in urine or tissue sections. Currently, there is no strictly defined therapeutic approach. This is the first retrospective analysis of human cases of dioctophymiasis. These review data will deepen our understanding of dioctophymiasis and help avoid misdiagnosis in clinical practice.

Dioctophyme renale (Nematoda: Dioctophymatidae) in Leopardus geoffroyi (Carnivora: Felidae) in the Neotropical region.

Parasitic diseases affecting wild carnivores remain largely unknown or poorly described. Dioctophymosis is a parasitosis caused by the nematode Dioctophyme renale that is found worldwide. It affects domestic and wild animals and has been reported frequently in Brazil. This paper reports dioctophymosis in a wild felid for the first time.

Occurrence of Dioctophyme renale larvae (Goeze, 1782) (Nematoda: Enoplida) in a new host from southern Brazil.

Dioctophymatosis is caused by the giant kidney worm Dioctophyme renale which occurs in dogs, cats, and wild mammals. In Brazil, the disease has been diagnosed in dogs from several states around the country. In the present study, the occurrence of D. renale larvae in snakes from southern of Brazil is reported. Three specimens of Philodryas patagoniensis (Serpentes: Dipsadidae) (common names in Brazil: "parelheira", "papa-pinto") roadkill in the county of Capão do Leão, State of Rio Grande do Sul, southern Brazil, were necropsied. Two third-stage larvae of D. renale were found in the coelomic cavity of P. patagoniensis. This study reveals a new host for D. renale larvae in the southern region of the State of Rio Grande do Sul, Brazil. This particular geographic area of the country has stood out as several cases of D. renale infection have been reported in a number of vertebrates from this region including domestic dogs and cats and wild animals such as carnivores, fish, and freshwater turtles.

[First report of Dioctophyma renale (Nematoda, Dioctophymatidae) in Colombia].

Dioctophymosis is a zoonotic parasitic disease caused by Dioctophyma renale (Goeze, 1782). It is distributed worldwide and it affects a large number of wild and domestic mammals.Here we report the first confirmed case of canine dioctophymosis in Colombia. The animal was found dead in the streets of the municipality of Yondó, Antioquia, and its dead body was taken to the Instituto Universitario de la Paz (UNIPAZ) to carry out a necropsy.A parasite worm was found in the right kidney and sent for identification to the Laboratorio de Parasitología of the Universidad de Santander (UDES). The specimen was identified as a male of D. renale upon observing the typical oval and transversely elongated bell-shaped bursa copulatrix with a spicule and no rays. Another important factor to confirm the diagnosis was the anatomical location in the kidney. This is the first time D. renale is reported in a stray dog in Colombia.

Ectopic infection by Dioctophyme renale in a dog from Georgia, USA, and a review of cases of ectopic dioctophymosis in companion animals in the Americas.

We report a case of ectopic dioctophymosis in an outdoor, eight-year-old spayed female, Coonhound-mix dog from Murrayville, Hall County, Georgia, USA. The dog presented to the clinic with an apparent puncture wound on her right, most caudal mammary gland, draining a serosanguinous discharge along with significant edema and thickening of the surrounding tissues. After initial physical examination the dog was placed into a cage awaiting diagnostic procedures. A couple of hours later, a bright red, live nematode was found in the bottom of the cage and submitted to the Parasitology Diagnostic Laboratory, Department of Infectious Diseases of the University of Georgia College of Veterinary Medicine. The specimen was morphologically identified as a female Dioctophyme renale, measuring 30 cm in length. The wound was cleaned with chlorhexidine solution. The patient was started on cefpodoxime 100 mg orally, once daily for 10 days. The dog had recent history of a mammary tumor on the left chain. After a week, an ultrasound examination confirmed integrity of the kidneys. Herein, we also provide a review on cases of ectopic dioctophymosis in companion animals in the Americas. Such cases are not uncommon, and nematodes may be found in various organs and tissues including the abdominal and thoracic cavities, scrotum, uterus, and mammary glands.

Giant kidney worm (Dioctophyma renale) infections in dogs from Northern Paraná, Brazil.

This article describes the pathological observations of Dioctophyma renale in dogs from the northern region of the State of Paraná, Brazil. A female, 6-year-old dog, Fila Brasileiro breed and a 16-year-old, male Poodle were diagnosed positive for D. renale during routine necropsy. Clinically, both dogs demonstrated hematuria, and the Poodle had a radiographic diagnosis of prostatic tumor, but neither had a clinical diagnosis of this infection prior to necropsy. Three giant worms were observed in the urinary bladder of the first case and one within the renal pelvis of the other dog. Histological findings were similar in both cases and represented compressive atrophy due to the presence of the nematode. Additionally, aspects of the life cycle, pathogenesis and epidemiology associated with this parasitism in Brazil are also discussed.