Serum enzymes and other laboratory tests in acute pancreatitis

This review evaluates selective enzymes and blood tests available for the diagnosis and prognosis of acute pancreatitis. It is concluded that serum amylase and lipase measurements represent the best available diagnostic methods. Newer alternative assays still require careful evaluation.

Effects of cyclosporin A on the splenic tissue of rats: a histomorphometric analysis

Histological studies demonstrated that long-term cyclosporin A treatment of nonantigenically challenged (untransplanted and unimmunized) Lewis rats markedly reduces the total percentage of splenic white pulp when compared to untreated control spleens (mean = 24 vs 34%, P less than 0.001). Direct measurements of periarteriolar sheaths and marginal zones demonstrated a marked reduction in size of these compartments in cyclosporin A-treated rats compared to untreated controls (P less than 0.001). In addition, there was a striking reduction in cellular density of the periarteriolar sheaths (P less than 0.001) and a minimal reduction in cellular density of the marginal zones (P less than 0.1) in the cyclosporin A-treated group when compared to untreated controls. There was no significant difference in total splenic size between the cyclosporin A-treated and the control groups, as indicated by total cross section measurements (mean = 33.3 vs 35.0, P less than 0.4). Qualitative observations of methyl green-pyroninophilic cells within and surrounding the marginal zones of the cyclosporin A-treated spleens revealed a much greater proportion of large pyroninophilic lymphocytes, which suggests that they are B immunoblasts. We conclude that long-term cyclosporin A treatment depletes splenic periarteriolar sheaths and marginal zones, compartments known to contain primary T lymphocytes, and induces an immunoblastic cell proliferation within the marginal zones and red pulp as well.

Arterialization of liver transplants in rats: I. Application of the tissue perfusion monitor in hemodynamic studies

This study demonstrates the use of the tissue perfusion monitor in the investigation of arterialization (using an arteriovenous fistula) of the heterotopic partial liver transplant. An index of peak perfusion rate was introduced as a reliable and accurate measure of the index of delivery rate of blood to the liver. Results revealed a significant (P less than .01) difference between arterialized and nonarterialized liver grafts when compared with their respective recipient host livers. Arterialization of grafted livers raised the index of peak perfusion rate to levels that were comparable to host livers. Arterialization also had a significant effect (P less than .01) on the host liver, whose values dropped by 74.26% when compared with the normal liver. Surprisingly, host values of the nonarterialized group fell by 61.54%. At this point, explanations for this phenomenon are speculatory. An extensive review of the literature exposes the variability in the observations of the role and usefulness of arterialization in hepatocellular function.

Histometric investigations of the effect of cyclosporin A on the testicular tissue of rats

The effect of cyclosporin A (CsA) on rat testes was assessed in Lewis rats which were given 10 mg/kg of CsA im per day. The rats were divided into 13 subgroups, and 1 subgroup was sacrificed each month. The rat testes were measured and examined for histometrical and morphological changes in comparison to controls. Histometrical analysis included testicular cross-sectional surface area, tubular density, tubular diameter, and the amounts of testicular germinal epithelium, lumen, and interstitial tissue. In the parameters examined, there were no overall differences between CsA-treated animals and controls. CsA does not affect rat testicular tissue.

Long-term studies of pancreas allotransplantation in experimental diabetes mellitus

Pancreaticoduodenal (PD) allografts (Brown Norway-alloxan-diabetic rats, n = 190) were treated with cyclosporin A (Cy-A) 10 mg/kg/daily and compared with nondiabetics with Cy-A treatment (n = 55), diabetics (n = 50), and diabetics with Cy-A treatment (n = 45). Body weight, blood sugar, blood insulin, blood urea nitrogen (BUN), and creatinine were monitored periodically; there were marked elevations of BUN and creatinine levels, indicating probably nephrotoxicity of Cy-A at this dosage. Some islet cell atrophy in the PD allografts was noted at the conclusion of the study. With respect to the immunosuppressive effect of Cy-A in alloxan diabetic rats, Brown Norway PD transplants into Lewis rats were successful and free of rejection for as long as 15 months post-transplantation. The body weight of these PD transplanted rats, however, never approached values representative of the nondiabetic rats. In our experience, the PD allograft model is acceptable in the clinical situation, particularly in children if the microsurgical technique is mastered and if the Cy-A regimen is used in combination with other immunosuppressant(s).

Survival in 1001 patients with carcinoma of the pancreas

Among 1001 patients with carcinoma of the pancreas, 23 of 912 patients with exocrine carcinomas, 10 of 46 with ampullary carcinomas, and 21 of 43 with malignant islet cell tumors survived 3 years. Of the survivors with exocrine cancers, there were nine of 97 patients who had curative operation, two had had palliative resections only, and one was an incidental microfocal carcinoma; in the remaining 11 patients a histologic origin in the pancreas was not established. Preoperatively suspected and histologically proven 3-year survivors included six patients with ductal adenocarcinomas, three patients with mucinous cystadenocarcinomas, one patient with acinic cell carcinoma, and one patient with microadenocarcinoma. Only two patients can be considered cured. Tumor size and lymph node status did not correlate with survival. Cystadenocarcinomas comprised 1% of cases but one third of 3-year survivors. Long-term survival in histologically confirmed pancreatic carcinoma is a rare event that cannot be predicted in the individual case.

Surgical treatment of chronic pancreatitis: an overview

The correct management of chronic pancreatitis remains undecided. The aims of surgical treatment are to relieve pain, treat complications and preserve pancreatic function. The appropriate surgical procedure to achieve these ends must be carefully chosen.

Non-insulin-mediated glucose uptake predominates in postabsorptive dogs

Overall glucose uptake represents the sum of insulin-mediated glucose uptake (IMGU) and non-insulin-mediated glucose uptake (NIMGU). In this study, we compared the rate of NIMGU in conscious and anesthetized dogs. Rates of glucose disposal were compared in the basal state and during severe insulinopenia after endogenous insulin suppression by high-dose somatostatin (SRIF) infusion. Steady-state NIMGU rates were calculated 2 h after commencing SRIF infusion. Three groups of studies were performed: 1) SRIF in conscious dogs; 2) SRIF in anesthetized dogs; and 3) SRIF plus glucagon, also in anesthetized dogs. In all three groups, serum insulin levels were reduced to below assay sensitivity after SRIF infusion. The basal metabolic clearance rate of glucose (MCRg) for each group was 3.8 +/- 0.4, 3.6 +/- 0.3, and 3.6 +/- 0.3 ml X kg-1 X min-1, respectively (P = NS, all groups). Steady-state NIMGU rates were 2.4 +/- 0.2 (conscious), 2.5 +/- 0.1 (anesthetized, SRIF only), and 2.4 +/- 0.1 ml/kg/min (anesthetized, SRIF plus glucagon). Thus, absolute rates of NIMGU expressed as MCRg in conscious and anesthetized animals do not differ and in the three groups studied comprise approximately the same proportion of the basal glucose uptake (approximately 64, approximately 69, and approximately 66%, respectively). We conclude that approximately 66% of basal postabsorptive glucose uptake occurs via NIMGU mechanisms and that this pathway is unaffected by anesthesia and surgery.

Hypoglycemic syndrome in infancy and childhood. A surgeon's perspective

Persistent, severe hypoglycemia due to inappropriate or excessive insulin secretion is an infrequent but devastating metabolic emergency in infancy and childhood. The primary therapeutic goal is to normalize blood glucose levels and to prevent the catastrophic sequelae of permanent brain damage and mental retardation due to refractory hypoglycemia. Overall, the use of diazoxide, the mainstay of medical treatment, has proved disappointing and has led to the reevaluation of aggressive, early surgical intervention. Currently, subtotal (80% to 90%) pancreatectomy is the most widely used operative procedure in the treatment of hyperinsulinism. It is, however, still associated with a relatively high failure rate, particularly in neonates or during early infancy when either nesidioblastosis or islet cell hyperplasia-both diffuse proliferative beta-cell disorders-is the most common cause of inappropriate insulin secretion. In these cases, "total" or "near-total" pancreatectomy may be necessary to control the hypoglycemic crisis.

Selective suppression of hepatic glucose output by human proinsulin in the dog

By using the euglycemic glucose-clamp technique we have observed the effects of comparable low dose proinsulin and insulin infusions on isotopically determined glucose turnover in 20 anesthetized dogs. In each animal somatostatin (SRIF) infusion was used to suppress endogenous pancreatic hormone secretion and basal glucagon was replaced. Peripheral proinsulin (0.083 micrograms X kg-1 X min-1) and insulin (350 microU X kg-1 X min-1) levels 15- to 20-fold higher than insulin on a molar basis, based on previous observations that proinsulin has only 5-10% the biologic potency of insulin. Three groups of infusion studies were performed: SRIF and glucagon (n = 5); SRIF, glucagon, and proinsulin (n = 10); and SRIF, glucagon, and insulin (n = 5). The mean serum proinsulin level of 2.43 +/- 0.36 pmol/ml achieved represented a 17-fold excess compared with the mean serum insulin level of 0.14 +/- 0.03 pmol (20 +/- 4 microU/ml). At these concentrations, both hormones reduced hepatic glucose production rates by approximately 50% to 2.0 +/- 0.2 mg X kg-1 X min-1 and 1.8 +/- 0.5 mg X kg-1 X min-1, respectively. In contrast, proinsulin failed to stimulate peripheral glucose utilization, whereas insulin led to a 2.0 +/- 0.3 mg X kg-1 X min-1 increment (approximately 50% increase) in glucose uptake (P less than 0.05). Thus at low infusion rates proinsulin exerts its effect predominantly by suppressing hepatic glucose production without measurable stimulation of peripheral glucose disposal. In contrast, for a comparable degree of hepatic glucose output suppression, insulin also significantly stimulates glucose disposal.

The role of clinical and biochemical criteria and endoscopic retrograde cholangiopancreatography in the urgent diagnosis of common bile duct stones in acute pancreatitis

The role of clinical and biochemical criteria in predicting common bile duct (CBD) stones was analyzed in 76 patients with acute pancreatitis undergoing endoscopic retrograde cholangiopancreatography (ERCP) during the same hospital admission. Forty patients had ERCP within 72 hours; cholangiography was successful in 92%. Fifty patients had biliary pancreatitis; 25 patients had CBD stones and all were successfully removed by endoscopic sphincterotomy (ES). Twenty-six patients had nonbiliary pancreatitis. Two patients had complications from ERCP and/or ES; two patients died (no CBD stones) but ERCP was noncontributory. Significant differences were found between the biliary and nonbiliary disease groups with respect to age, and bilirubin. gamma-glutamyl transpeptidase, alkaline phosphatase, alanine transaminase, and amylase levels. The first four factors also discriminated between those patients with and without CBD stones. Logistic discriminant functions were estimated providing probabilities for the presence of CBD stones for each patient but were too cumbersome for clinical use. A simple scoring system was devised on the basis of cut-off levels: bilirubin greater than or equal to 40 mumol/L, gamma-glutamyl transpeptidase greater than or equal to 250 IU/L, alkaline phosphatase greater than or equal to 225 IU/L, and age greater than or equal to 70 years, indicating CBD stones. Bilirubin alone had a sensitivity and specificity of 80%; the specificity increased to 93% with all four factors. These results suggest that clinical and biochemical criteria and ERCP and/or ES may have important roles in the management of patients with suspected biliary pancreatitis.

Glucose counterregulation in patients after pancreatectomy. Comparison with other clinical forms of diabetes

Glucose and counterregulatory hormone responses to a high-dose (1.7 mU/kg/min) insulin infusion were studied in 6 patients who had undergone total pancreatectomy, and the results were compared with those of normal controls and patients with other clinical forms of diabetes. The maximum increase in the plasma glucagon concentration during hypoglycemia in the pancreatectomized patients (5 +/- 5.6 pg/ml) was less than in normals (121 +/- 22 pg/ml). Type I diabetic subjects (28 +/- 14 pg/ml), and insulin-treated diabetic subjects of recent onset (36 +/- 12 pg/ml) also had reduced responses, while responses were normal in type II diabetic subjects (102 +/- 26 pg/ml). The epinephrine response to the hypoglycemic stimulus was reduced after pancreatectomy (278 +/- 81 pg/ml) and in type I diabetic subjects (628 +/- 244 pg/ml), but was not different from control (858 +/- 126 pg/ml) in type II and recent-onset diabetic patients. There was considerable overlap in counterregulatory hormone responses in individual patients with and without autonomic neuropathy and with normal or undetectable fasting C-peptide concentrations. While the control subjects all experienced symptoms of hypoglycemia within a narrow range of plasma glucose concentrations (35-46 mg/dl), five of the diabetic subjects experienced symptoms of hypoglycemia at plasma glucose levels of greater than or equal to 55 mg/dl, and five had no subjective awareness of hypoglycemia despite plasma glucose levels less than 30 mg/dl.(ABSTRACT TRUNCATED AT 250 WORDS)

Pancreatic hormone profiles and metabolism posthepatectomy in the dog. Evidence for a hepatotrophic role of insulin, glucagon, and pancreatic polypeptide

Gut-related peptide hormones, especially insulin and glucagon, have been implicated in promoting hepatic regeneration. To elucidate the interrelationship between pancreatic peptide hormones and hepatic regenerative activity, we evaluated pancreatic hormone levels and their metabolism before and over a 15-day period after limited (42%) and extended (72%) hepatectomy in the dog. Serum insulin, glucagon, and pancreatic polypeptide levels increased significantly after both limited and extended hepatectomy but not after sham laparotomy. In the case of glucagon only, these increases were related to the extent of liver resection. No significant changes in plasma somatostatin levels were observed posthepatectomy. Plasma glucose levels remained normal throughout the period of study. Metabolic clearance rates and plasma half-lives for insulin, glucagon, and pancreatic polypeptide did not change over the study period. Peripheral C-peptide/insulin molar ratios were unchanged posthepatectomy, indicating no change in hepatic insulin extraction. In the absence of demonstrable changes in hormone metabolism or metabolic stimuli to secretion, these increases in pancreatic hormone levels, coinciding with the period of known maximal hepatic regenerative activity, are compatible with the notion that these are hepatotrophic responses, which could conceivably be mediated by humoral feedback signals from the liver to the endocrine pancreas.

Naloxone decreases centrally induced hyperglycemia in dogs. Evidence for an opioid role in glucose homeostasis

Intracerebroventricular (ICV) instillation of morphine and beta-endorphin causes centrally induced hyperglycemia. Locally active, endogenous opioids in the central nervous system may, therefore, also be involved in the elevation of blood sugar. This possibility was tested by examining the glucoregulatory response to central glucoprivation induced by ICV administration of 2-deoxy-D-glucose (2DG) in dogs. Administration of 2DG resulted in a rise in plasma glucose and immunoreactive glucagon (IRG) of 108 +/- 19 mg/dl and 70 +/- 20 pg/ml, respectively. These changes were attenuated by the simultaneous central infusion of the opiate antagonist naloxone: plasma glucose levels increased by 77 +/- 14 mg/dl and IRG by 43 +/- 3 pg/ml, both significantly different from the effect of 2DG alone (P less than 0.05-0.01). These findings suggest that opiate receptors participate in the counterregulatory response to central glucoprivation. They also provide a mechanism by which endogenous opioid peptides may play a role in the central regulation of glucose homeostasis.

Pancreatic biopsy

The necessity, value, and safety of various techniques of pancreatic biopsy are evaluated. The authors also offer a general policy on pancreatic biopsies.

Management of pancreatic trauma

Twenty patients who sustained pancreatic trauma are reviewed. Eighteen of the patients underwent emergency laparotomy and there were 53 major associated injuries. Three patients died, giving an operative mortality of 17%. All deaths could be directly attributed to the severity and extent of the associated injuries. Eleven of the 15 survivors following emergency operation developed serious postoperative complications which, in 6 instances, were directly related to the pancreatic injury. Two patients were initially treated conservatively because the isolated pancreatic injuries were missed. Both developed complications requiring operation.

Metabolism of C-peptide in the dog. In vivo demonstration of the absence of hepatic extraction

The in vivo hepatic metabolism of connecting peptide (C-peptide) in relation to that of insulin has not been adequately characterized. A radioimmunoassay for dog C-peptide was therefore developed and its metabolism studied in conscious mongrel dogs, with sampling catheters chronically implanted in their portal and hepatic veins and femoral artery. The hepatic extraction of endogenous C-peptide under basal conditions was negligible (4.3 +/- 4.5%) and was similar to the hepatic extraction of C-peptide measured during the constant exogenous infusion of C-peptide isolated from dog pancreas. Simultaneously measured hepatic extraction of endogenous and exogenously infused insulin were 43.8 +/- 7.6 and 47.5 +/- 4.4%, respectively. The metabolic clearance rate of infused C-peptide was 11.5 +/- 0.8 ml/kg per min and was constant over the concentration range usually encountered under physiological conditions. In additional experiments, the effect of parenteral glucose administration on the hepatic extraction of C-peptide and insulin was investigated. The hepatic extraction of C-peptide (6.2 +/- 4.0%) was again negligible in comparison with that of insulin (46.7 +/- 3.4%). Parenteral glucose administration did not affect the hepatic extraction of either peptide irrespective of whether it was infused peripherally, intraportally, or together with an intraportal infusion of gastrointestinal inhibitory polypeptide. The fasting C-peptide insulin molar ratio in both the portal vein (1.2 +/- 0.1) and femoral artery (2.1 +/- 0.3) was also unaffected by the glucose stimulus. These results therefore indicate that, since the hepatic extraction of C-peptide is negligible and its clearance kinetics linear, the peripheral C-peptide concentration should accurately reflect the rate of insulin secretion. New approaches to the quantitation of hepatic extraction and secretion of insulin by noninvasive techniques are now feasible.

Hormonal control of biliary lipid secretion in dogs

Five dogs were anesthetized, their cystic ducts were ligated, and their common bile ducts cannulated. The experiments were divided into four 1-hour periods. Taurocholic acid (18 mumol/min) and pipenzolate methylbromide (0.5 mg/kg body weight initially followed by 0.1 mg/kg body weight/20 minutes) were infused during all periods. Somatostatin (800 ng/kg/min) was infused during periods 2, 3, and 4 to suppress the endogenous secretion of peptide hormones. During periods 3 and 4, insulin was infused into a mesenteric vein at rates of 0.2 mU/kg/min and 0.8 mU/kg/min, respectively. These rates have been shown to produce fasting and postprandial portal vein insulin levels. Bile was collected during each period and the volume, bile acid concentration, and biliary lipid content were measured. Another five dogs were studied in a similar way, except that glucagon was infused in place of insulin at rates of 0.6 and 3.0 ng/kg body weight/min to produce fasting and postprandial portal vein levels. The results show that 1) the biliary secretion of cholesterol and phospholipid is increased by pharmacologic doses of somatostatin and 2) physiologic doses of glucagon, but not insulin , suppress the biliary secretion of cholesterol and phospholipid.