Diarrea crónica como manifestación de un tumor neuroendocrino / Chronic diarrhea as a manifestation of a neuroendocrine tumor

Resumen Las neoplasias neuroendocrinas (Neuroendocrine Neoplasms, NEN) constituyen un grupo heterogéneo de neoplasias poco frecuentes, que se originan en las células endocrinas, con la capacidad de secretar aminas y polipéptidos hormonales. Las NEN de localización pancreática (pNEN) pueden ser funcionales o no funcionales. Las pNEN funcionales secretan hormonas como la gastrina, la insulina y el glucagón y otras menos frecuentes como el péptido intestinal vasoactivo (PIV), por lo que sus características sindromáticas dependen del péptido secretado. Los vipomas se manifiestan con diarrea crónica de características secretoras, que usualmente conducen a trastornos hidroelectrolíticos e incluso a complicaciones serias asociadas como la falla renal. A continuación, se describe el caso de un hombre de 37 años con diarrea crónica de 6 meses de evolución y frecuentes hospitalizaciones por trastornos hidroelectrolíticos, generados por hipocalemia severa y lesión renal aguda por deshidratación. Después de múltiples estudios, se considera el diagnóstico de una diarrea secretora por NEN funcional, secretora de PIV. Por tanto, se inicia una terapia empírica con octreotida y se logra controlar la diarrea, así como corregir el trastorno hidroelectrolítico. Además, se amplían los estudios, para documentar las pNEN tratadas mediante intervención quirúrgica, con respuesta clínica favorable y remisión completa de la sintomatología.

Abstract Neuroendocrine tumors (NETs) are a heterogeneous group of rare neoplasms that originate in endocrine cells with the ability to secrete amines and hormonal polypeptides. Pancreatic neuroendocrine tumors (PNETs) can be functional or non-functional. Functional PNETs secrete common hormones such as gastrin, insulin and glucagon and much less frequent hormones such as vasoactive intestinal peptide (VIP). Their characteristics depend on the peptide secreted. Vipomas are characterized by chronic diarrhea of ​​secretory characteristics that usually lead to hydroelectrolytic disorders and can lead to serious complications associated with renal failure. This article describes the case of a 37-year-old man who had suffered chronic diarrhea with frequent hospitalization for hydroelectrolytic disorders for six months due to severe hypokalemia and acute renal damage due to dehydration. After multiple studies, a diagnosis of secretory diarrhea due to a VIP secretory functional NET was considered. Empirical therapy with Octreotide was begun to control diarrhea and correct the hydroelectrolytic disorder. More studies of PNETS are being published. They have been treated surgically intervention with favorable clinical results and complete remission of symptoms.

Application Progress in CFTR Inhibitors in the Treatment of Secretory Diarrhea / 中国药师

Secretory diarrhea provides a major health challenge worldwide, which is one of the most important reasons for children morbidity and death. The activation of Cl- channels in intestinal epithelial cells resulting in the excessive fluid secretion in the intestine is the main reason of diarrhea caused by enterotoxins. In diarrhea caused by cholera and the other bacterial enterotoxins, cystic fibrosis transmembrane conductance regulator ( CFTR) is the main cAMP-control Cl- channel to promote the fluid secretion in epithelial cells. Therefore, CFTR inhibitors are the new choices for secretory diarrhea. CFTR inhibitors include thiazolidinone, glycine hydrazide and quinoxalinedione chemical classes, and some components from natural plants also exhibit CFTR inhibition activity, however, further studies should be done.

From Escherichia coli heat-stable enterotoxin to mammalian endogenous guanylin hormones

The isolation of heat-stable enterotoxin (STa) from Escherichia coli and cholera toxin from Vibrio cholerae has increased our knowledge of specific mechanisms of action that could be used as pharmacological tools to understand the guanylyl cyclase-C and the adenylyl cyclase enzymatic systems. These discoveries have also been instrumental in increasing our understanding of the basic mechanisms that control the electrolyte and water balance in the gut, kidney, and urinary tracts under normal conditions and in disease. Herein, we review the evolution of genes of the guanylin family and STa genes from bacteria to fish and mammals. We also describe new developments and perspectives regarding these novel bacterial compounds and peptide hormones that act in electrolyte and water balance. The available data point toward new therapeutic perspectives for pathological features such as functional gastrointestinal disorders associated with constipation, colorectal cancer, cystic fibrosis, asthma, hypertension, gastrointestinal barrier function damage associated with enteropathy, enteric infection, malnutrition, satiety, food preferences, obesity, metabolic syndrome, and effects on behavior and brain disorders such as attention deficit, hyperactivity disorder, and schizophrenia.

A Case of Villous Adenoma with Depletion Syndrome / 대한소화기내시경학회지

Massive secretory diarrhea with pre-renal insufficiency, hyponatremia, hypokalemia and metabolic alkalosis or acidosis is associated with some large villous adenomas of the rectum and is called with depletion syndrome. This characteristic fluid and electrolyte depletion syndrome is caused by secretion of sodium, potassium, and fluid from the tumor. PGE2 formation in the villous adenoma appears to be the cause of fluid secretion by the abnormal tumor epithelium. Surgical removal of villous adenoma is the only promising therapy, In case of inoperability, denial of surgical intervention or just for palliative treatment prior to surgery, the use of PG synthetase inhibitors may facilitate the correction of severe fluid-electrolyte deficits. We reported a case of large villous adenoma of the rectum with depletion syndrome aceompanied by secretory diarrhea and fluid and electrolyte depletion with metabolic alkalosis due to severe vomiting.