ABSTRACT
The pancreas remains a difficult organ to evaluate using laboratory methods alone. No single laboratory test is diagnostic of pancreatitis (chronic or acute) without other diagnostic modalities concurring with the diagnosis or ruling out other diseases. The diagnosis of pancreatitis is particularly difficult in cats, and pancreatitis often occurs with other diseases. The use of pancreatic cytology may be useful in diagnosing both inflammation and neoplasia. Exocrine pancreatic insufficiency (EPI) can be relatively easily diagnosed when clinically manifested by the measurement of trypsinlike immunoreactivity. Diagnosis is more difficult when EPI is subclinical.
Subject(s)
Clinical Chemistry Tests/veterinary , Exocrine Pancreatic Insufficiency/veterinary , Pancreatic Diseases/veterinary , Pancreatic Function Tests/veterinary , Animals , Cats , Clinical Chemistry Tests/trends , Clinical Enzyme Tests/trends , Clinical Enzyme Tests/veterinary , Diagnosis, Differential , Dogs , Early Diagnosis , Exocrine Pancreatic Insufficiency/etiology , Pancreatic Diseases/diagnosis , Pancreatic Diseases/metabolism , Pancreatic Diseases/physiopathology , Pancreatic Elastase/blood , Pancreatic Function Tests/trendsABSTRACT
Las células responden a niveles bajos de oxígeno (hipoxia) activando un programa génico específico para potenciar la adaptación al metabolismo anaeróbico y promover la conservación de la energía. Los factores de transcripción HIF (del inglés hypoxia inducible factor) juegan un papel central en la respuesta a hipoxia. La actividad de HIF está regulada por el gen supresor de tumores VHL, que degrada a HIF en presencia de oxígeno. Recientemente varios estudios han puesto de manifiesto la importancia de la ruta de respuesta a hipoxia HIF en la homeostasis de la glucosa. Cambios en los niveles de actividad de esta ruta en la célula beta endocrina alteran la capacidad de secreción de insulina. Además, la ruta de respuesta a hipoxia HIF parece regular la función metabólica de órganos implicados en la patogénesis de la diabetes y el síndrome metabólico como el hígado, el tejido adiposo y el músculo. Estas observaciones sugieren la posibilidad de que alteraciones en la ruta de hipoxia HIF puedan contribuir al desarrollo de diabetes
Under low oxygen pressure (hypoxia), cells activate a specific genetic program, modulating genes involved in anaerobic metabolism and cellular energy metabolism. The transcriptional hypoxia inducible factors (HIFs) are central to this response. HIF activity is regulated by the von Hippel-Lindau tumour suppressor protein (pVHL). In the presence of oxygen, pVHL targets HIF for ubiquitination and subsequent proteasomal degradation. Several recent reports have revealed a critical role of the hypoxia response mediated by HIF on glucose homeostasis. Changes in HIF pathway activity in beta-cells impair insulin secretion. Furthermore, the HIF pathway regulates the metabolic function in organs involved in the pathogenesis of diabetes and metabolic syndrome such as liver, fat and muscle. These observations raise the question of whether changes in HIF levels might contribute to the progression of type 2 diabetes
Subject(s)
Animals , Male , Female , Insulin Infusion Systems/standards , Insulin Infusion Systems/trends , Insulin Infusion Systems , Pancreatic Function Tests/trends , Exocrine Pancreatic Insufficiency/diagnosis , Hypoxia-Inducible Factor 1/metabolism , Hypoxia-Inducible Factor 1/pharmacology , Hypoxia-Inducible Factor 1/pharmacokineticsABSTRACT
The diagnosis of Chronic Pancreatitis (CP) is based on the detection of abnormal structure or function of the diseased pancreas. The pancreatic function tests more accurately determine the presence of CP than tests of structure, especially for early stage disease. The function tests can be divided into two categories: non-invasive and invasive. The invasive "tube" tests can reliably detect mild, early CP, but are only available at a few referral centers and tend to be poorly tolerated by patients. The non-invasive tests are easy to obtain, but tend to perform poorly in patients with early, mild disease. Therefore, no one test is useful in all clinical situations, and a detailed understanding of the rational, pathophysiologic basis, strengths, and limitations of various tests is needed. This review highlights the role of various pancreatic function tests in the diagnosis of CP including fecal fat analysis, fecal elastase, fecal chymotrypsin, serum trypsin, the secretin stimulation test, the cholecystokinin (CCK) stimulation test, the combined secretin-CCK stimulation test, the intraductal and endoscopic secretin stimulation tests, and the functional magnetic resonance imaging of the pancreas after secretin stimulation.
Subject(s)
Pancreas/physiopathology , Pancreatic Function Tests/trends , Pancreatitis, Chronic/diagnosis , Disease Progression , History, 21st Century , Humans , Pancreas/pathology , Pancreatic Function Tests/history , Pancreatitis, Chronic/physiopathology , Predictive Value of Tests , Severity of Illness IndexABSTRACT
Although techniques for high-resolution imaging of the pancreas are constantly being improved, the evaluation of pancreatic function remains crucial for the workup of pancreatic diseases. More than 20 direct and indirect tests are available for the assessment of pancreatic function. Measurement of fecal elastase-1 is recommended as the most suitable test for the initial assessment of pancreatic function. Among other techniques, the pancreolauryl test, and alternatively the BT-PABA (N-benzoyl-L-tyrosyl-p-aminobenzoic acid) or the (13)C-mixed-triglyceride test, yield the best sensitivity and specificity. Nevertheless, all indirect tests are of limited value in patients with mild to moderate impairment of pancreatic function. In these patients, the secretin-caerulein test remains the gold standard.
