• 1.

    Davis JL, Jones SL. Suppurative cholangiohepatitis and enteritis in adult horses. J Vet Intern Med. 2003;17(4):583587.

  • 2.

    Peek SF, Divers TJ. Medical treatment of cholangiohepatitis and cholelithiasis in mature horses: 9 cases (1991–1998). Equine Vet J. 2000;32(4):301306.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3.

    Rasche A, Lehmann F, Goldmann N, et al. A hepatitis B virus causes chronic infections in equids worldwide. Proc Natl Acad Sci U S A. 2021;118(13):e2013982118. doi:10.1073/pnas.2013982118

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4.

    Tomlinson JE, Kapoor A, Kumar A, et al. Viral testing of 18 consecutive cases of equine serum hepatitis: a prospective study (2014–2018). J Vet Intern Med. 2019;33(1):251257.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5.

    Tomlinson JE, Tennant BC, Struzyna A, et al. Viral testing of 10 cases of Theiler’s disease and 37 in-contact horses in the absence of equine biologic product administration: a prospective study (2014–2018). J Vet Intern Med. 2019;33(1):258265.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 6.

    Divers TJ, Tennant BC, Kumar A, et al. New parvovirus associated with serum hepatitis in horses after inoculation of common biological product. Emerg Infect Dis. 2018;24(2):303310.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 7.

    Ross PF, Ledet AE, Owens DL, et al. Experimental equine leukoencephalomalacia, toxic hepatosis, and encephalopathy caused by corn naturally contaminated with fumonisins. J Vet Diagn Invest. 1993;5(1):6974.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 8.

    Caloni F, Cortinovis C. Toxicological effects of aflatoxins in horses. Vet J. 2011;188(3):270273.

  • 9.

    Stegelmeier BL, Colegate SM, Brown AW. Dehydropyrrolizidine alkaloid toxicity, cytotoxicity, and carcinogenicity. Toxins (Basel). 2016;8(12):356. doi:10.3390/toxins8120356

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 10.

    Lacerda MDSC, Wilson TM, Argenta VLS, et al. Crotalaria spectabilis poisoning in horses fed contaminating oats. Toxicon. 2021;197:611.

  • 11.

    Pearson EG. Liver failure attributable to pyrrolizidine alkaloid toxicosis and associated with inspiratory dyspnea in ponies: three cases (1982–1988). J Am Vet Med Assoc. 1991;198(9):16511654.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12.

    Thornburg LP, Kintner LD. Cholangiohepatitis in a horse. Vet Med Small Anim Clin. 1980;75(12):18951896.

  • 13.

    Pearson EG. Liver disease in the mature horse. Equine Vet Educ. 1999;11(2):8796.

  • 14.

    Buote M. Cholangiohepatitis and pancreatitis secondary to severe gastroduodenal ulceration in a foal. Can Vet J. 2003;44(9):746748.

  • 15.

    Tegtmeyer B, Echelmeyer J, Pfankuche VM, et al. Chronic equine hepacivirus infection in an adult gelding with severe hepatopathy. Vet Med Sci. 2019;5(3):372378.

    • Search Google Scholar
    • Export Citation
  • 16.

    Tomlinson JE, Jager M, Struzyna A, et al. Tropism, pathology, and transmission of equine parvovirus-hepatitis. Emerg Microbes Infect. 2020;9(1):651663.

  • 17.

    Pfaender S, Cavalleri JM, Walter S, et al. Clinical course of infection and viral tissue tropism of hepatitis C virus-like nonprimate hepaciviruses in horses. Hepatology. 2015;61(2):447459.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 18.

    Ramsay JD, Evanoff R, Wilkinson, TE Jr, Divers TJ, Knowles DP, Mealey RH. Experimental transmission of equine hepacivirus in horses as a model for hepatitis C virus. Hepatology. 2015;61(5):15331546.

    • Search Google Scholar
    • Export Citation
  • 19.

    Mendel VE, Witt MR, Gitchell BS, et al. Pyrrolizidine alkaloid-induced liver disease in horses: an early diagnosis. Am J Vet Res. 1988;49(4):572578.

  • 20.

    Lessard P, Wilson WD, Olander HJ, Rogers QR, Mendel VE. Clinicopathologic study of horses surviving pyrrolizidine alkaloid (Senecio vulgaris) toxicosis. Am J Vet Res. 1986;47(8):17761780.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 21.

    Johnson AL, Divers TJ, Freckleton ML, et al. Fall panicum (Panicum dichotomiflorum) hepatotoxicosis in horses and sheep. J Vet Intern Med. 2006;20(6):14141421.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 22.

    Nation PN. Hepatic disease in Alberta horses: a retrospective study of ‘alsike clover poisoning’ (1973–1988). Can Vet J. 1991;32(10):602607.

  • 23.

    Nyaoke AC, Navarro MA, Beingesser J, Uzal FA. Infectious necrotic hepatitis caused by Clostridium novyi type B in a horse: case report and review of the literature. J Vet Diagn Invest. 2018;30(2):294299.

    • Search Google Scholar
    • Export Citation
  • 24.

    Borchers A, Magdesian KG, Halland S, Pusterla N, Wilson WD. Successful treatment and polymerase chain reaction (PCR) confirmation of Tyzzer’s disease in a foal and clinical and pathologic characteristics of 6 additional foals (1986–2005). J Vet Intern Med. 2006;20(5):12121218.

    • Search Google Scholar
    • Export Citation
  • 25.

    Durham AE. Association between forage mycotoxins and liver disease in horses. J Vet Intern Med. 2022;36(4):15021507.

  • 26.

    Cullen JM, Stalker MJ. Liver and biliary system. In: Maxie MG, ed. Jubb, Kennedy, and Palmer’s Pathology of Domestic Animals. 6th ed. Elsevier Inc; 2016:258352.

    • Search Google Scholar
    • Export Citation
  • 27.

    Lee SK, Park D, Lee I. Molecular prevalence of equine parvovirus-hepatitis in the sera of clinically healthy horses in South Korea. Vet Sci. 2021;8(11):282. doi:10.3390/vetsci8110282

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 28.

    Badenhorst M, de Heus P, Auer A, et al. Active equine parvovirus-hepatitis infection is most frequently detected in Austrian horses of advanced age. Equine Vet J. 2022;54(2):379389.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 29.

    Meister TL, Tegtmeyer B, Brüggemann Y, et al. Characterization of equine parvovirus in Thoroughbred breeding horses from Germany. Viruses. 2019;11(10):965. doi:10.3390/v11100965

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 30.

    Okano N, Yamamoto K, Sakaguchi K, et al. Clinicopathological features of acute-onset autoimmune hepatitis. Hepatol Res. 2003;25(3):263270.

  • 31.

    Bulle F, Mavier P, Zafrani ES, et al. Mechanism of gamma-glutamyl transpeptidase release in serum during intrahepatic and extrahepatic cholestasis in the rat: a histochemical, biochemical and molecular approach. Hepatology. 1990;11(4):545550.

    • Search Google Scholar
    • Export Citation
  • 32.

    DeNotta SL, Divers TJ. Clinical pathology in the adult sick horse: the gastrointestinal system and liver. Vet Clin North Am Equine Pract. 2020;36(1):105120.

    • PubMed
    • Search Google Scholar
    • Export Citation

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A seasonal idiopathic hepatitis syndrome in horses presented to a Midwestern veterinary teaching hospital

Sandra D. TaylorDepartment of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Janice E. KritchevskyDepartment of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Patrick HuangDepartment of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Carla OlaveDepartment of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Sarah J. WaxmanDepartment of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Margaret A. MillerDepartment of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN

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Abstract

OBJECTIVE

To report history, clinical examination findings, clinicopathologic findings, diagnostic test results, treatment, and outcome in horses with a novel idiopathic hepatitis syndrome.

ANIMALS

13 client-owned horses.

PROCEDURES

Medical records of horses that were presented with fever and increased blood liver enzyme activity over a 16-month period were reviewed (December 1, 2020, to April 1, 2022). Collected data included signalment, history, clinical and clinicopathologic findings, diagnostic test results, treatment, clinical progression, and short-term outcome.

RESULTS

Affected horses were presented between December and April of each of the 2 seasons investigated. The majority of horses developed cyclic fevers over the course of 3 weeks, during which time histologic evidence of hepatitis was observed. Histologic lesions included hepatic necrosis, neutrophilic to lymphohistiocytic inflammation, biliary epithelial injury, and portal fibrosis. Systemic inflammation was evidenced by increased serum amyloid A concentration and leukon changes. No horse developed signs of hepatic insufficiency, and all horses clinically recovered. Return of serum activity of GGT to within the reference range occurred within 16 weeks in most horses. Histologic lesions remained evident up to 27 weeks after initial presentation in 1 horse.

CLINICAL RELEVANCE

Although an etiologic agent has not been identified, an apparently seasonal equine hepatitis syndrome was characterized by fever, systemic inflammation, increased liver enzyme activity, and histologic evidence of hepatitis. An infectious cause is suspected on the basis of histology and outcome.

Abstract

OBJECTIVE

To report history, clinical examination findings, clinicopathologic findings, diagnostic test results, treatment, and outcome in horses with a novel idiopathic hepatitis syndrome.

ANIMALS

13 client-owned horses.

PROCEDURES

Medical records of horses that were presented with fever and increased blood liver enzyme activity over a 16-month period were reviewed (December 1, 2020, to April 1, 2022). Collected data included signalment, history, clinical and clinicopathologic findings, diagnostic test results, treatment, clinical progression, and short-term outcome.

RESULTS

Affected horses were presented between December and April of each of the 2 seasons investigated. The majority of horses developed cyclic fevers over the course of 3 weeks, during which time histologic evidence of hepatitis was observed. Histologic lesions included hepatic necrosis, neutrophilic to lymphohistiocytic inflammation, biliary epithelial injury, and portal fibrosis. Systemic inflammation was evidenced by increased serum amyloid A concentration and leukon changes. No horse developed signs of hepatic insufficiency, and all horses clinically recovered. Return of serum activity of GGT to within the reference range occurred within 16 weeks in most horses. Histologic lesions remained evident up to 27 weeks after initial presentation in 1 horse.

CLINICAL RELEVANCE

Although an etiologic agent has not been identified, an apparently seasonal equine hepatitis syndrome was characterized by fever, systemic inflammation, increased liver enzyme activity, and histologic evidence of hepatitis. An infectious cause is suspected on the basis of histology and outcome.

Contributor Notes

Corresponding author: Dr. Taylor (taylo248@purdue.edu)