Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA.
J Vet Intern Med. 2010 Jan-Feb;24(1):140-4. doi: 10.1111/j.1939-1676.2009.0429.x.
Heterobilharzia americana (HA), the causative agent of canine schistosomiasis, is a flatworm with a freshwater snail as an intermediate host. Only case reports or small case series evaluating naturally infected dogs have been published.
Describe clinical signs in dogs naturally infected with HA.
Twenty-two dogs naturally infected with HA from 1985 to 2009.
Retrospective study. All medical records were searched for HA and schistosomiasis. Only dogs with a diagnosis based on identification of ova on histopathology or fecal saline sedimentation were included.
The median age was 3.1 years (1-12). The median duration of clinical signs before diagnosis was 0.63 months (0.03-12). The most common clinical signs were lethargy (91%), weight loss (77%), hyporexia (68%), vomiting (59%), and diarrhea (55%). Eleven of the 22 dogs were hypercalcemic. Hypercalcemia did not resolve without definitive treatment with praziquantel. HA infection was an incidental diagnosis in 7/22 dogs. Diagnosis was obtained via necropsy (4), histopathology (9), and fecal examination (9). Definitive treatment included praziquantel and fenbendazole. Eighteen dogs were diagnosed antemortem and 17 were treated. Twelve dogs were alive for 6 months to 3 years after diagnosis.
HA infection occurs in younger, larger breed, indoor dogs. Hypercalcemia does not resolve without praziquantel treatment. Prognosis is good and neither hypercalcemic-induced renal failure nor ascites appears to worsen prognosis. Dogs in affected areas or that have traveled to affected areas that present for weight loss, gastrointestinal or liver disease, and hypercalcemia, should be tested.
美洲双腔吸虫（HA）是犬血吸虫病的病原体，是一种扁形动物，其中间宿主为淡水蜗牛。仅有关于自然感染犬的病例报告或小病例系列发表。
描述自然感染 HA 的犬的临床症状。
1985 年至 2009 年期间，22 只自然感染 HA 的犬。
回顾性研究。所有病历均进行 HA 和血吸虫病搜索。仅包括基于组织病理学或粪便盐水沉淀中发现卵来诊断的犬。
中位年龄为 3.1 岁（1-12 岁）。确诊前临床症状的中位持续时间为 0.63 个月（0.03-12 个月）。最常见的临床症状是嗜睡（91%）、体重减轻（77%）、食欲不振（68%）、呕吐（59%）和腹泻（55%）。22 只犬中有 11 只是高钙血症。未经吡喹酮明确治疗，高钙血症不会消退。7/22 只犬为 HA 感染的偶发诊断。通过尸检（4 例）、组织病理学（9 例）和粪便检查（9 例）获得诊断。明确治疗包括吡喹酮和芬苯达唑。18 只犬在生前确诊，17 只接受了治疗。诊断后 6 个月至 3 年内，12 只犬存活。
HA 感染发生在年龄较小、体型较大、室内饲养的犬中。未经吡喹酮治疗，高钙血症不会消退。预后良好，高钙血症引起的肾衰竭或腹水似乎不会使预后恶化。应在出现体重减轻、胃肠道或肝脏疾病和高钙血症的受影响地区的犬或曾前往过受影响地区的犬进行检测。
