Gastrinoma and Zollinger-Ellison syndrome in canids: a literature review and a case in a Mexican gray wolf.

Gastrinoma, an infrequent diagnosis in middle-aged dogs, occurs with nonspecific gastrointestinal morbidity. Laboratory tests can yield a presumptive diagnosis, but definitive diagnosis depends on histopathology and immunohistochemistry. We describe a malignant pancreatic gastrinoma with lymph node metastases and corresponding Zollinger-Ellison syndrome in a Mexican gray wolf ( Canis lupus baileyi) and review this endocrine neoplasm in domestic dogs. A 12-y-old, captive, male Mexican gray wolf developed inappetence and weight loss. Abdominal ultrasonography revealed a thickened duodenum and peritoneal effusion. Two duodenal perforations were noted on exploratory celiotomy and were repaired. Persisting clinical signs led to a second celiotomy that revealed a mesenteric mass, which was diagnosed histologically as a neuroendocrine carcinoma. During the following 16 mo, the wolf received a combination of H2-receptor antagonists, proton-pump inhibitors, gastroprotectants, and anti-emetics, but had recurrent episodes of anorexia, nausea, acid reflux, and remained underweight. Worsening clinical signs and weakness prompted euthanasia. The antemortem serum gastrin concentration of 414 ng/L (reference interval: 10-40 ng/L) corroborated hypergastrinemia. Autopsy revealed a mass expanding the right pancreatic limb; 3 parapancreatic mesenteric masses; duodenal ulcers; focal duodenal perforation with septic fibrinosuppurative peritonitis; chronic-active ulcerative esophagitis; and poor body condition. The pancreatic mass was diagnosed histologically as a neuroendocrine carcinoma and the parapancreatic masses as lymph node metastases. Immunohistochemistry of the pancreatic mass was positive for gastrin and negative for glucagon, insulin, pancreatic polypeptide, serotonin, somatostatin, and vasoactive intestinal peptide.

Diarreas neuroendocrinas / Neuroendocrine diarrheas

Los cuadros endocrinos son poco frecuentes pero en ellos un porcentaje importante de casos presenta diarrea. Estas diarreas son crónicas; hipersecretoras y abundantes (volúmenes diarios de heces mayores de 500 ml) y en su mayoría son debidas a neoplasias funcionales benignas o malignas, que estimulan la secreción de agua y electrólitos en las criptas de Liberkuhn y también la motilidad intestinal

Diarreas endocrinas secretoras / Secretory endocrine diarrhea

Se precisa el concepto de diarrea y se señalan las clasificaciones de mayor utilidad práctica. Se definen como diarreas endocrinas las que se deben a sustancias circulantes de naturaleza polipeptídica que modifican la actividad secretora y motora del tracto gastrointestinal. La mayoría de estas sustancias son producidas por células argentófilas del sistema APUD. Entre las diarreas endocrinas secretoras se analizan el Síndrome de Zollinger-Ellison, el Síndrome de Verner Morrison y el Síndrome Carcinoideo. El primero es debido a hipergastrinemia de origen ectópico (hiperplasia o tumor de células no beta) y los dos últimos a hipersecreción de péptido intestinal vaso-activo por células PP del sistema APUD y de serotonina respectivamente

[Zollinger-Ellison syndrome. Report of a case]. / Síndrome de Zollinger-Ellison. Informe de un caso.

A 61 years old male with Z-E syndrome is reported. He presented gastrointestinal bleeding, abdominal pain, slightly elevated gastrin and hypoglycemia. He underwent total gastrectomy, a non-resectable tumor of the tail of the pancreas with liver metastasis were found. A biopsy of the liver metastasis and the gastric mucosa were reviewed under the light and the transmission electronic microscopes. The gastric mucosa showed abundant parietal cells. The metastatic hepatic tissue was poorly differentiated under the light microscope and the electron micrographs revealed tissue resembling pancreatic islands of Langerhans with granules in the cytoplasm, this means that the neoplasm originated from APUD cells.