Hepatic capillariasis (Capillaria hepatica) in porcupines (Erethizon dorsatum) in Pennsylvania

Canine hepatic calodiosis with cirrhosis

The nematode parasite Calodium hepaticum (Capillaria hepatica) has a global distribution and is commonly reported in rodents (definitive host), dogs, cats and wild animals. Humans especially children are more susceptible to the parasitic infection. This paper documents an incidental finding of hepatic calodiosis with cirrhosis in a stray dog and discusses the zoonotic implications. A non descript dog was brought for necropsy examination to the Department of Veterinary Pathology, Madras Veterinary College, Tamil Nadu, India. Liver appeared dark brown, mottled with multifocal random variably sized, grey white flat firm areas. Histopathologically, liver tissue revealed multiple random encysted large collection of eggs surrounded by mild inflammation with a few lymphocytes, macrophages and fine fibrosis. The eggs had characteristic barrel shape, bipolar ends, bilayered wall, cross striations between the walls, and yolk. Periodic acid Schiff stain demonstrated the glycolic wall of ova. Marked portal to portal fibrosis was demonstrated by Masson's trichrome (for collagen) and by Warthin-Starry (for reticulin) stains. The stage of parasitic infection was diagnosed as intermediate to chronic due to fibrosis. A need to study the prevalence of the disease in rodents, human and animals is emphasized. Improper burial of carcasses of rodents and dogs may contribute to spread of infection. Pets and stray animals may transmit infection to human and pose health risk.

Atypical Dermatophytosis in 12 North American Porcupines (Erethizon dorsatum) from the Northeastern United States 2010-2017

Twelve wild North American porcupines (Erethizon dorsatum) out of a total of 44 of this species examined in an 8-year period were diagnosed with dermatopathies while being cared for at two wildlife rehabilitation clinics. Biopsy and necropsy were performed on seven and five animals, respectively. Atypical dermatophytosis was diagnosed in all cases. Lesions consisted of diffuse severe epidermal hyperkeratosis and mild hyperplasia with mild lymphoplasmacytic dermatitis and no folliculitis. Dermatophytes were noted histologically as hyphae and spores in hair shafts, and follicular and epidermal keratin. Trichophyton sp. was grown in 5/6 animals where culture was performed, with a molecular diagnosis of Arthroderma benhamiae/Trichophyton mentagrophytes in these five cases. Metagenomic analysis of formalin-fixed paraffin-embedded tissue samples from three cases identified fungi from 17 orders in phyla Basidiomycota and Ascomycota. Alteration of therapy from ketaconazole, which was unsuccessful in four out of five early cases, to terbinafine or nitraconazole led to the resolution of disease and recovery to release in four subsequent animals. In all, six animals were euthanized or died due to dermatopathy, no cases resolved spontaneously, and six cases were resolved with therapy. The work we present demonstrates an atypical lesion and anatomical distribution due to dermatophytosis in a series of free-ranging wild porcupines and the successful development of novel techniques for extracting and sequencing nucleic acids from fungus in archival formalin-fixed paraffin-embedded animal tissue.

Clinical and laboratory characterizations of hepatic capillariasis

Hepatic capillariasis is a rare and neglected parasitic disease caused by infection with Capillaria hepatica in human liver. The disease is not well described and the information for the disease's clinical manifestation, laboratory findings and disease management strategy is not well reported. The limited information for this neglected infection often results in the delay of diagnosis or misdiagnosed to other diseases, therefore the real prevalence or severity of the infection may be underestimated. More case report with systemic analysis and features summary of this disease is needed to better understand the serious zoonotic disease. This study included systemic analysis of 16 patients infected with hepatic capillariasis in China between 2011-2017, including clinical manifestations, laboratory/radiative image findings and treatment results. Clinical manifestation included sustained fever (56.25%), respiratory disorder (37.5%), abdominal pain (37.5%), diarrhea (25%), leukocytosis (93.75%) and eosinophilia (100%). No egg was detected in feces of all patients. Over 60% patients showed elevated level of hepatic enzymes and proteins related to liver fibrosis in sera. Ultrasound and MRI examinations displayed scattered parasitic granuloma leisure in affected liver. Liver biopsy revealed parasite eggs, necrotized parasitic granulomas and septal fibrosis. Treatment with albendazole combined with corticoids for several treatment courses cured all patients with capillariasis. The difficulty of diagnosis, apparent damage of liver functions and potential fibrosis make the disease's prevalence and severity underestimated.

Hepatic Lipidosis and other Test Findings in Two Captive Adult Porcupines (Erethizon Dorsatum) Dying from a “Sudden Death Syndrome”

Routine postmortem examination and histologic evaluation of tissue sections demonstrated hepatic lipidosis (HL) in 2 adult captive porcupines with a history of sudden death. The male porcupine had a markedly enlarged pale liver that microscopically showed large unilocular vacuoles within hepatocellular cytoplasm. The periparturient female had similar but less marked hepatic lesions and an incidental pulmonary mycosis. These findings suggest HL as an important differential of spontaneous death in captive porcupines. It is hypothesized that in addition to the widely documented causes, HL in captive porcupines may be specifically associated with nutritional imbalances caused by the feeding of unsuitable commercial diets. The possible association of the condition with dietary and other factors in captive porcupines needs to be thoroughly investigated.

An overview of the host spectrum and distribution of Calodium hepaticum (syn. Capillaria hepatica): part 2-Mammalia (excluding Muroidea)

Calodium hepaticum (syn. Capillaria hepatica) is a globally distributed zoonotic nematode with low host specificity and a high affinity to the liver. Although murid rodents are the main definite hosts, various other mammals can be affected with hepatic capillariasis: non-murid rodents, Insectivora, Chiroptera, Lagomorpha, Artiodactyla, Perissodactyla, Hyracoidea, Marsupialia, Carnivora, and Primates. Overall, more than 180 mammalian species (including humans) are known as suitable hosts of this pathogen. This review gives an overview of the distribution and host spectrum of C. hepaticum in non-Muroidean mammals in wildlife and zoos as well as in domesticated and laboratory animals. Furthermore, the role of spurious infections in animals and the dissemination of C. hepaticum by mammalian and non-mammalian animals are summarized.

Capillaria hepatica in China

Capillaria hepatica (C. hepatica) is a parasitic nematode causing hepatic capillariasis in numerous mammals. Ecologic studies showed that the first hosts of C. hepatica were rodents, among which rats had relatively high infection rates, which explains why C. hepatica spreads globally. Anatomical studies showed that the liver was the principal site of colonization by these parasites and physical damage tended to occur. Although C. hepatica might lead to serious liver disorders, relevant clinical reports were rare, because of the non-specific nature of clinical symptoms, leading to misdiagnosis. This review mainly focuses on the biological characteristics and epidemiology of C. hepatica in China and histopathologic changes in the liver, with expectation of gaining a better understanding of the disease and seeking more effective treatment.

Prevalence of Calodium hepaticum (Syn. Capillaria hepatica) in house mice (Mus musculus) in the Azores archipelago

Calodium hepaticum (Syn. Capillaria hepatica) is a zoonotic liver nematode of mammals distributed worldwide. Rodents are believed to be the main reservoirs of this nematode. In this paper, prevalence of the parasite was analyzed in liver histological sections from 51 house mice (Mus musculus) caught in human-inhabited houses, from two localities (Furnas and Rabo de Peixe) on São Miguel island from the Azores archipelago (Portugal). Mean prevalence of infection was 19.6%, with 33.3% prevalence in Furnas and 4.1% in Rabo de Peixe (P=0.07). No significant differences were found between the prevalence of infection and the age, body weight and the sex of mice. Hepatic lesions found were either acute and/or chronic stage and consisted of moderate to severe multifocal pyogranulomatous hepatitis with encapsulated eggs with typical bipolar plugs and moderate to severe necrotizing hepatitis consistent with larva tracks. Periportal inflammatory infiltration, hepatocyte regeneration and bile duct hyperplasia were also noted. In most cases, hepatic lesions occupied more than 50% of the liver, but despite severe lesions, in some mice, no signs of hepatic failure were noticed. The high rate of infection found in the present study suggests that house mice are an important reservoir for this parasite in the Azores and could have a role in human transmission.