Disseminated intravascular coagulation and antiprotease activity in acute human pancreatitis

Anticoagulation Therapy for Splanchnic Vein Thrombosis Associated With Acute Pancreatitis: A Systematic Review and Meta-Analysis

Splanchnic vein thrombosis (SVT) is not rare in patients with acute pancreatitis. It remains unclear about whether anticoagulation should be given for acute pancreatitis-associated SVT. The PubMed, EMBASE, and Cochrane Library databases were searched. Rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were pooled and compared between patients with acute pancreatitis-associated SVT who received and did not receive therapeutic anticoagulation. Pooled rates and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated. Heterogeneity among studies was evaluated. Overall, 16 studies including 698 patients with acute pancreatitis-associated SVT were eligible. After therapeutic anticoagulation, the pooled rates of SVT recanalization, any bleeding, death, intestinal ischemia, portal cavernoma, and gastroesophageal varices were 44.3% (95%CI = 32.3%-56.6%), 10.7% (95%CI = 4.9%-18.5%), 13.3% (95%CI = 6.9%-21.4%), 16.8% (95%CI = 6.9%-29.9%), 21.2% (95%CI = 7.5%-39.5%), and 29.1% (95%CI = 16.1%-44.1%), respectively. Anticoagulation therapy significantly increased the rate of SVT recanalization (RR = 1.69; 95%CI = 1.29-2.19; P < .01), and marginally increased the risk of bleeding (RR = 1.98; 95%CI = 0.93-4.22; P = .07). The rates of death (RR = 1.42; 95%CI = 0.62-3.25; P = .40), intestinal ischemia (RR = 2.55; 95%CI = 0.23-28.16; P = .45), portal cavernoma (RR = 0.51; 95%CI = 0.21-1.22; P = .13), and gastroesophageal varices (RR = 0.71; 95%CI = 0.38-1.32; P = .28) were not significantly different between patients who received and did not receive anticoagulation therapy. Heterogeneity was statistically significant in the meta-analysis of intestinal ischemia, but not in those of SVT recanalization, any bleeding, death, portal cavernoma, or gastroesophageal varices. Anticoagulation may be effective for recanalization of acute pancreatitis-associated SVT, but cannot improve the survival. Randomized controlled trials are warranted to further investigate the clinical significance of anticoagulation therapy in such patients.

Multiple extra-splanchnic venous thromboses - an unusual vascular complication of acute pancreatitis

Acute pancreatitis (AP) is an acute inflammatory process of the pancreas with variable clinical presentations. Splanchnic venous thrombosis is a well-known vascular complication of AP and commonly present as thrombosis of the splanchnic venous system: splenic vein (SplV), portal vein (PV) and superior mesenteric vein (SMV), either separately or in combinations. Involvement of extra-splanchnic vessels is rare and associated with morbidity and mortality. Vascular complications are late phenomena and usually associated with local complications of AP, namely acute fluid collections, necrotizing pancreatitis and walled-off pancreatic necrosis. Pathogenesis of venous thrombosis is multifactorial in which pancreatic inflammation and systemic inflammatory response play a key role. At present, there are no consensus guidelines on treatment and use of anticoagulation for venous thrombosis in the setting of AP. Limited literature suggests the use of anticoagulation in presence of PV with or without SMV thrombosis and extrasplanchnic vessel involvement. Literature on extra-splanchnic vessels involvement in acute pancreatitis is sparse. Here we present two cases with multiple extra-splanchnic vessels involvement and their management.

Splanchnic Venous Thrombosis in Acute Pancreatitis: Does Anticoagulation Affect Outcome?

Background

Splanchnic venous system thrombosis is a well recognized local vascular complication of acute pancreatitis (AP). It may involve thrombosis of splenic vein (SplV), portal vein (PV) and superior mesenteric vein (SMV), either separately or in combinations, and often detected incidentally, indeed some cases present with upper gastrointestinal bleed, bowel ischemia and hepatic decompensation. Incidence is variable depending on study subjects and diagnostic modalities. Pathogenesis is multifactorial centered on local and systemic inflammation. Management involves treatment of underlying AP and its complications. Universal use of anticoagulation may lead to increased risk of bleeding due to frequent need of interventions (radiologic/endoscopic/surgical). Literature on anticoagulation in setting of AP is sparse and at present there is no consensus guideline on it. Current article details our experience on splanchnic venous thrombosis (SVT) in AP in a well defined cohort of patients at a tertiary care center.

Methods

Hospitalized patients with AP from January 2018 to December 2018 were included in the study. Detailed information on demographic, clinical, laboratory, radiologic features, and indication of anticoagulation use were collected prospectively during the index admission. Outcome variables were analyzed at the end of 6 months.

Results

Twenty four out of 105 (22.85%) patients with AP develop SVT. Etiology of AP was alcohol use in 21/24 (87.5%) subjects. Most common vessel involved was isolated SplV in 11/24 (45.8%) patients followed by SplV along with PV and SMV 9/24 (37.50%, P < 0.001). Bowel ischemia 4/12 (33.3%), hepatic decompensation 3/12 (25%), triple vessel involvement 4/12 (33.3%) and pulmonary embolism 1/12 (8.3%) were reasons for anticoagulation. There was no statistical difference with respect to development of varices, collateral formation, recanalization, bleeding and mortality with use of anticoagulation (P > 0.05 with respect to all above variables).

Conclusions

SVT is commonly seen in alcohol-induced AP. Anticoagulation does not affect outcomes of SVT. Subset of patients may benefit with anticoagulation.

Serum Concentrations of Angiopoietin-2 and Soluble fms-Like Tyrosine Kinase 1 (sFlt-1) Are Associated with Coagulopathy among Patients with Acute Pancreatitis

In severe acute pancreatitis (SAP), systemic inflammation leads to endothelial dysfunction and activation of coagulation. Thrombotic disorders in acute pancreatitis (AP) include disseminated intravascular coagulation (DIC). Recently, angiopoietin-2 and soluble fms-like tyrosine kinase 1 (sFlt-1) were proposed as markers of endothelial dysfunction in acute states. Our aim was to assess the frequency of coagulation abnormalities in the early phase of AP and evaluate the relationships between serum angiopoietin-2 and sFlt-1 and severity of coagulopathy. Sixty-nine adult patients with AP were recruited: five with SAP, 15 with moderately severe AP (MSAP) and 49 with mild AP. Six patients were diagnosed with DIC according to International Society on Thrombosis and Haemostasis (ISTH) score. All patients had at least one abnormal result of routine tests of hemostasis (low platelet count, prolonged clotting times, decreased fibrinogen, and increased D-dimer). The severity of coagulopathy correlated with AP severity according to 2012 Atlanta criteria, bedside index of severity in AP and duration of hospital stay. D-dimers correlated independently with C-reactive protein and studied markers of endothelial dysfunction. Angiopoietin-2, D-dimer, and ISTH score were best predictors of SAP, while sFlt-1 was good predictor of MSAP plus SAP. In clinical practice, routine tests of hemostasis may assist prognosis of AP.

The Interplay between Inflammation, Coagulation and Endothelial Injury in the Early Phase of Acute Pancreatitis: Clinical Implications

Acute pancreatitis (AP) is an inflammatory disease with varied severity, ranging from mild local inflammation to severe systemic involvement resulting in substantial mortality. Early pathologic events in AP, both local and systemic, are associated with vascular derangements, including endothelial activation and injury, dysregulation of vasomotor tone, increased vascular permeability, increased leukocyte migration to tissues, and activation of coagulation. The purpose of the review was to summarize current evidence regarding the interplay between inflammation, coagulation and endothelial dysfunction in the early phase of AP. Practical aspects were emphasized: (1) we summarized available data on diagnostic usefulness of the markers of endothelial dysfunction and activated coagulation in early prediction of severe AP; (2) we reviewed in detail the results of experimental studies and clinical trials targeting coagulation-inflammation interactions in severe AP. Among laboratory tests, d-dimer and angiopoietin-2 measurements seem the most useful in early prediction of severe AP. Although most clinical trials evaluating anticoagulants in treatment of severe AP did not show benefits, they also did not show significantly increased bleeding risk. Promising results of human trials were published for low molecular weight heparin treatment. Several anticoagulants that proved beneficial in animal experiments are thus worth testing in patients.

Risk factors and outcome of splanchnic venous thrombosis in patients with necrotizing acute pancreatitis

BACKGROUND

Splanchnic venous thrombosis (SVT) is considered a rare but important complication in patients with acute pancreatitis (AP) and literatures regarding this topic were sparse. The aim of the present study was to investigate the risk factors of SVT in necrotizing acute pancreatitis (NAP) and assess the prognosis of these patients.

METHODS

Both univariate and multivariate logistic regression analyses were applied using 15 indices including age, gender, Acute Physiology and Chronic Health Evaluation II scores (APACHE II), CRP (C - reactive protein) levels, etc to explore potential risk factors for the development of SVT in NAP patients. Moreover, clinical outcome measures such as mortality, organ failure and length of hospital and ICU stay were also compared between NAP patients with or without SVT.

RESULTS

According to the statistical results, only intra-abdominal pressure (IAP) was proved to be an independent risk factor for SVT (OR, 1.283; 95% CI, 1.091-1.509,P=0.003). In addition, Balthazar's CT score and occurrence of IPN (infected pancreatic necrosis) also reached statistical significance (P=0.040 and 0.047, respectively), but the 95% confidence interval shown in the multivariate logistic regression suggested that the observed ORs are not significant (1.326;95% CI 0.984-1.787 and 2.61;95 CI 0.972-7.352, respectively), which indicates weaker association between the two parameters and SVT. Regarding the clinical outcomes, patients with SVT showed higher mortality, longer hospital and intensive care unit duration, higher rates of a variety of complications and more utilization of invasive interventions.

CONCLUSIONS

IAP is an independent risk factor for the development of SVT in patients with NAP, while Balthazar's CT score and occurrence of IPN are also associated with SVT, although not as strong as IAP. Moreover, occurrence of SVT relates with extremely poor prognosis in NAP patients, evidenced by increased mortality, morbidity and need for invasive interventions.

Splanchnic vein thrombosis in acute pancreatitis: a single-center experience

OBJECTIVES

This study aimed to estimate outcomes of splanchnic vein thrombosis (SVT) in hospitalized patients with acute pancreatitis (AP).

METHODS

This was a retrospective study (January 1996 to December 2006) via chart review.

RESULTS

Over 10 years, 1.8% (45/2454) of patients with AP with a mean (SD) age of 58 (15) years were diagnosed with SVT. Splenic vein thrombosis was the most common form of SVT (30/45 patients, 67%). Seventeen patients were anticoagulated with heparin, when the SVT was diagnosed in the acute stage followed by oral anticoagulation (AC). The thrombosis that was most commonly anticoagulated was portal vein thrombosis in 11 (65%) of 17 patients. Of 17 patients in the AC group, 2 (12%) showed recanalization as compared with 3 (11%) of 28 patients in the non-AC group (P > 0.05). The mortality was 3 (7%) of 45 (2 from the AC group versus 1 in the non-AC group, P > 0.05). Two of these died of multiorgan failure, and the other, from septic shock. None of the deaths were due to bleeding complications.

CONCLUSIONS

Splanchnic vein thrombosis occurred in 1.8% patients of AP. The use of AC was reasonably safe with no fatal bleeding complications. However, there was no significant difference in the recanalization rates in those with and without AC.

Splanchnic venous thrombosis and pancreatitis

Pancreatitis is an inflammatory process with local and systemic manifestations. One such local manifestation is thrombosis in splanchnic venous circulation, predominantly of the splenic vein. The literature on this important complication is very sparse. This review offers an overview of mechanism of thrombosis, its pathophysiology, diagnosis, and management in the setting of acute as well as chronic pancreatitis.

The clinical course of acute pancreatitis and the inflammatory mediators that drive it

Acute pancreatitis (AP) is a common emergency condition. In the majority of cases, it presents in a mild and self-limited form. However, about 20% of patients develop severe disease with local pancreatic complications (including necrosis, abscess, or pseudocysts), systemic organ dysfunction, or both. A modern classification of AP severity has recently been proposed based on the factors that are causally associated with severity of AP. These factors are both local (peripancreatic necrosis) and systemic (organ failure). In AP, inflammation is initiated by intracellular activation of pancreatic proenzymes and/or nuclear factor-κB. Activated leukocytes infiltrate into and around the pancreas and play a central role in determining AP severity. Inflammatory reaction is first local, but may amplify leading to systemic overwhelming production of inflammatory mediators and early organ failure. Concomitantly, anti-inflammatory cytokines and specific cytokine inhibitors are produced. This anti-inflammatory reaction may overcompensate and inhibit the immune response, rendering the host at risk for systemic infection. Currently, there is no specific treatment for AP. However, there are several early supportive treatments and interventions which are beneficial. Also, increasing the understanding of the pathogenesis of systemic inflammation and the development of organ dysfunction may provide us with future treatment modalities.

Plasma thrombin-activatable fibrinolysis inhibitor as an indicator of inflammation and disease severity in acute pancreatitis

AIM

In addition to suppressing fibrinolysis, thrombin activatable fibrinolysis inhibitor (TAFI) was suggested to be involved in inflammation. To date, no study has been published that reports the role of TAFI in acute pancreatitis (AP). Therefore, the objective of the present study was to investigate the role of plasma TAFI as an indicator of inflammation in AP, and its association with disease severity.

METHODS

Plasma TAFI antigen levels quantitatively determined by using ELISA kits in 21 AP patients at onset and remission and 17 healthy controls. Associations of TAFI with inflammatory markers to determine AP and disease severity were assessed. To predict the severity of AP, modified Glasgow prognostic score (mGPS) and computerized tomography severity index (CTSI) were used for each subject.

RESULTS

Plasma TAFI levels was higher in AP patients at onset of the disease compared with healthy controls. The disease severity according to mGPS was significantly correlated with TAFI levels. Overall, accuracy of TAFI in determining AP was 83.3% with a sensitivity, specificity, NPV and PPV of 80.9%, 85.7%, 81.8%, and 85% respectively (AUC: 0.915).

CONCLUSIONS

The present study for the first time demonstrated that TAFI is elevated in AP. The appraisal of TAFI levels in patients with AP in conjunction with other markers of inflammation may provide additional information in estimating AP severity.

Thrombin generation in vitro and in vivo, and disturbed tissue factor regulation in patients with acute pancreatitis

BACKGROUND

Being a central link between inflammation and coagulation, tissue factor (TF) and its inhibitor (TFPI) might be associated with the severity of acute pancreatitis (AP) and the development of organ failure (OF).

METHODS

The study comprises 9 severe AP patients with OF and 24 reference patients (11 mild AP and 13 severe AP without OF). Plasma samples were collected on admission. TF-induced thrombin generation in plasma samples was studied using the thrombogram method. In vivo thrombin generation was estimated by prothrombin fragment F1+2. Free and total TFPI levels were measured. To evaluate coagulation status the activated partial thromboplastin time, prothrombin time, platelet count, D-dimer, fibrinogen, antithrombin (AT) 3 and protein C (PC) were determined.

RESULTS

There was no significant difference in F1+2 levels between the patient groups. Patients with severe AP tended to show low platelet counts, PC and AT3 levels, and high D-dimer levels. In 11 patients the standard TF stimulation did not trigger thrombin generation in the thrombogram. All deaths occurred in these patients. Free TFPI levels and free/total TFPI ratios were significantly higher in these patients and in non-survivors.

CONCLUSION

Failure of TF-initiated thrombin generation in the thrombogram assay explained by high levels of circulating free TFPI may be associated with OF and mortality in AP. and IAP.

Plasma tissue factor pathway inhibitor levels in patients with acute pancreatitis

BACKGROUND

In acute pancreatitis (AP), disorders of the coagulation-fibrinolysis system are closely related to the severity of the AP and to organ dysfunctions. We previously reported that plasma tissue factor (TF) levels were elevated in patients with AP, particularly in cases of alcoholic AP with pancreatic necrosis. Tissue factor pathway inhibitor (TFPI) is a key regulator of the extrinsic coagulation pathway, but plasma TFPI levels in AP have not yet been determined.

METHODS

Plasma TFPI concentrations were measured by enzyme-linked immunosorbent assay in 44 patients with AP on admission. The relationships between AP severity, pancreatic necrosis, organ dysfunction, infection, and prognosis were analyzed.

RESULTS

Plasma TFPI levels were increased in AP patients compared with healthy volunteers. Plasma TFPI levels in severe AP were greater than those in mild AP. Plasma TFPI levels significantly correlated with Ranson score, APACHE II score, and Japanese severity score. Plasma TFPI levels in patients with pancreatic necrosis were greater than those in patients without pancreatic necrosis. Plasma TFPI levels in patients with organ dysfunction were greater than those in patients without organ dysfunction. In patients with pancreatic necrosis, the TF/TFPI ratios in non-survivors were lower than those in survivors. Moreover, the mortality rates in patients with TF/TFPI ratios > or = 2.0 were lower than those in patients with TF/TFPI ratios < 2.0.

CONCLUSIONS

Plasma TFPI levels were significantly increased in patients with AP, and the elevation was markedly related to the severity, pancreatic necrosis and organ dysfunctions. The imbalance of TF and TFPI may influence the disease state and thereby the prognosis in AP.

Low-Volume Continuous Hemodiafiltration With Nafamostat Mesilate Increases Trypsin Clearance Without Decreasing Plasma Trypsin Concentration in Severe Acute Pancreatitis

Continuous hemodiafiltration (CHDF) has recently been used for treatment of severe acute pancreatitis. CHDF is capable of eliminating small molecules from blood, but whether trypsin can be eliminated by CHDF is not clear. In this study, elimination of trypsin-like enzyme activity (TLE) and cationic trypsin-like immunoreactivity (TLI) using low-volume CHDF was examined at the first CHDF session in eight patients with severe acute pancreatitis. CHDF was performed with a polysulfone hemofilter (membrane area, 0.7 m2) and nafamostat mesilate, a protease inhibitor and anticoagulant, at a blood flow rate of 100 ml/min and a filtration and dialysis flow rate of 10 ml/min each. Before beginning CHDF, plasma TLE was 3.41 +/- 2.86 nmol/(ml.min), and TLI was 5,900 +/- 9,008 ng/ml. The average plasma clearances of TLE and TLI achieved by the circuit during the 12-hour therapy were 56.7 +/- 4.9 ml/min and 8.0 +/- 7.2 ml/min, respectively. The average plasma clearance of TLI into the waste fluid was 2.4 +/- 1.6 ml/min whereas TLE was below the measurable sensitivity. The plasma concentration of TLE and TLI remained unchanged. These results indicate that low-volume CHDF using nafamostat mesilate as an anticoagulant can increase trypsin plasma clearance. However, low-volume CHDF is not effective to eliminate the plasma trypsin concentration.

Pancreas recovery following cerulein-induced pancreatitis is impaired in plasminogen-deficient mice

BACKGROUND & AIMS

The plasminogen (plg) system participates in tissue repair in several organs, but its role in pancreas repair remains poorly characterized. To understand better the role of plg in pancreas recovery following injury, we examined the course of cerulein-induced pancreatitis in plg-deficient and -sufficient mice.

METHODS

Pancreatitis was induced by cerulein administration (50 microg/kg, 7 intraperitoneal injections). Mice were killed either at the acute phase (7 hours after the first cerulein injection) or during recovery (at 2, 4, and 7 days). In pancreatic sections, we examined pancreatic morphology, trypsin activation, inflammatory cell infiltration, acinar cell death, cell proliferation, extracellular matrix deposition, activation of stellate cells (PSCs), and components of the plg and metalloproteinase systems.

RESULTS

In plg-sufficient mice, pancreatic plg levels and plasmin activity increased during the acute phase and remained elevated during recovery. Pancreatitis resolved in plg-sufficient mice within 7 days. Pancreas recovery involved reorganization of the parenchyma structure, removal of necrotic debris, cell proliferation, transient activation of PSCs, and moderate deposition of extracellular matrix proteins. Acute pancreatitis (7 hours) was indistinguishable between plg-deficient and -sufficient mice. In contrast, pancreas recovery was impaired in plg-deficient mice. Plg deficiency led to disorganized parenchyma, extensive acinar cell loss, poor removal of necrotic debris, reduced cell proliferation, and fibrosis. Fibrosis was characterized by deposition of collagens and fibronectin, persistent activation of PSCs, and up-regulation of pancreatic transforming growth factor beta1.

CONCLUSIONS

Plg/plasmin deficiency leads to features similar to those found in chronic pancreatitis such as parenchymal atrophy and fibrosis.

Applicability of disseminated intravascular coagulation parameters in the assessment of the severity of acute pancreatitis

OBJECTIVES

To evaluate the clinical applicability of the determination of disseminated intravascular coagulation (DIC) parameters in acute pancreatitis.

METHODS

The subjects for this study were 139 consecutive patients with acute pancreatitis. DIC parameters were assessed at the initial observation of these patients.

RESULTS

The levels of the DIC parameters at admission were significantly associated with the severity and the prognosis of acute pancreatitis. Antithrombin III (AT-III), fibrin/fibrinogen degradation products-E, platelet count, D-dimer, and thrombin-AT-III complex at admission showed better area under the receiver operating characteristics curve values compared with C-reactive protein. An AT-III value of 69% at admission was the best cut-off value to predict fatal outcome (sensitivity, 81%; specificity, 86%).

CONCLUSIONS

The aggravated coagulation parameters predict a fatal outcome in patients with acute pancreatitis. AT-III level (<69%) was the most accurate marker for poor outcome of acute pancreatitis at admission.

Disorders of hemostasis during the surgical management of severe necrotizing pancreatitis

OBJECTIVES

Several clinical studies of severe necrotizing pancreatitis (SNP) suggest profound activation of coagulation as well as activation of the fibrinolytic system. The aim of this study was to evaluate the hemostatic derangements in patients who were managed for SNP.

METHODS

Forty-one operated-on patients with SNP were analyzed regarding clinical outcome and activation of the coagulation systems. Serial measurement of coagulation, anticoagulation, and fibrinolysis parameters: prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, antithrombin III (AT III), protein C, plasminogen activator inhibitor-1 (PAI-1), d-dimer, alpha2-antiplasmin, and plasminogen were performed on days 1, 3, 5, 7, 10, and 14 after the initial operation. According to treatment outcome at the end of study, groups of 26 survivors and 15 nonsurvivors were compared.

RESULTS

Nonsurvivors had significantly lower levels of activity of protein C and AT III, and higher concentrations of d-dimer and PAI-1 than survivors. The other measured parameters did not show significant differences between the compared groups of patients.

CONCLUSIONS

Changes in protein C, AT III, d-dimer and PAI-1 levels indicate exhaustion of fibrinolysis and coagulation inhibitors in patients with poor outcome during the course of SNP.

Inhibition of human pancreatic proteinases by human plasma α2-antiplasmin and antithrombin

Human plasma alpha1-antitrypsin inhibits human pancreatic trypsin, chymotrypsin and elastase, which are massively released into the blood stream during acute pancreatitis. To examine whether the plasma proteins of individuals with genetic deficiency of alpha1-antitrypsin are protected against the deleterious action of these enzymes by other inhibitors, we have tested their inhibition by alpha2-antiplasmin and antithrombin. We have determined the inhibition rate constants kass and calculated d(t), the in vivo inhibition time. Surprisingly, trypsin is inhibited faster by alpha2-antiplasmin [kass=2.5 x 10(6) M(-1)S(-1), d(t)=2.3 s] and antithrombin [kass=1.7 x 10(5) M(-1)s(-1), d(t)=5.8 s] than by alpha1-antitrypsin [d(t)=17 s or 116 s in alpha1-antitrypsin-sufficient or alpha1-antitrypsin-deficient individuals, respectively]. Low molecular weight heparin accelerates the inhibition of trypsin by antithrombin by a factor of 16 [d(t)=0.36 s]. Antithrombin and alpha2-antiplasmin are not physiological inhibitors of chymotrypsin and elastase. These enzymes are, however, physiologically inhibited by alpha1-antitrypsin and alpha1-antichymotrypsin even in alpha1-antitrypsin-deficient individuals. We conclude that (i) low molecular weight heparin may be helpful in the management of acute pancreatitis, and (ii) genetically determined alpha1-antitrypsin deficiency probably does not lead to a significantly increased risk of plasma protein degradation during this disease.

Coagulative disorders in human acute pancreatitis: role for the D-dimer

INTRODUCTION AND AIMS

We investigated coagulative disorders, particularly the role of the D-dimer, in acute pancreatitis where coagulation abnormalities related to disease severity are known to occur.

METHODOLOGY

D-dimer levels in 30 patients with acute pancreatitis were evaluated; pancreatitis was mild and uncomplicated in 11 patients, accompanied by complications in 15, and severe in 4. We attempted to find a relationship between the D-dimer level and the antithrombin III level, prothrombin time, partial thromboplastin time, the C-reactive protein level, and results of routine laboratory tests.

RESULTS

In the 11 patients with uncomplicated pancreatitis, the D-dimer level increased about 1.5 times over the limit, while in the 15 patients with complications and the four patients with severe pancreatitis, the D-dimer level increased about seven times above the normal limit; this difference was highly significant (p < 0.0001). The rise in the D-dimer level was inversely related to albumin and calcium levels (p = 0.0001) and directly related to the C-reactive protein level, fibrinogen level and leukocyte count (p = 0.0001), prothrombin time (p = 0.006), partial thromboplastin time (p = 0.03), and acute abdominal collections and lung involvement (p = 0.0001). The increase appeared early on, lasting for the entire study and peaking on days 3-6.

CONCLUSIONS

The D-dimer is the expression of pancreatitis and the extension of systemic involvement; it may be considered a prominent link in the chain of events leading to severe disease.

Impaired mononuclear phagocyte function in patients with severe acute pancreatitis: evidence from studies of plasma clearance of trypsin and monocyte phagocytosis

Activated proteases in plasma are complexed by alpha 2-macroglobulin. Although the complexes retain peptidase activity, they are usually eliminated promptly by mononuclear phagocytes. In severe acute pancreatitis, almost 30% of plasma alpha 2-macroglobulin becomes complexed, suggesting impaired clearance. In the present study, plasma [methyl-14C]trypsin clearance and monocyte phagocytosis were investigated. Attacks complicated by major organ-system failure, pancreatic pseudocyst, abscess, or necrosis were graded severe (median Ranson score 5.5). Plasma [methyl-14C]trypsin half-life was significantly increased in severe attacks (N = 7, median 21.1 min), compared to mild attacks (N = 14, median 15.4 min, P < 0.05) and healthy controls (N = 4, median 10.8 min, P < 0.02). Monocyte phagocytosis was significantly lower in severe attacks (N = 9, median 3.6%) compared to mild attacks (N = 20, median 20.8%, P < 0.01) and healthy controls (N = 8, median 26.9%, P < 0.01). Plasma [methyl-14C]trypsin half-life and monocyte phagocytosis were significantly inversely correlated (r = -0.51, P < 0.01). Impaired clearance of circulating trypsin in acute pancreatitis is potentially deleterious but may be reversed by stimulating mononuclear phagocytes.

Fibrinolytic enzymes in ascites during experimental acute pancreatitis in rats

The ascites accumulating during acute pancreatitis contain proteases that play a role in the progression of this disease. The proteases of the fibrinolytic system in the ascites were therefore studied in experimental acute pancreatitis induced in rats. Synthetic substrate assay and the fibrin plate method revealed high activities of proteases, including plasminogen activator, in the ascites. The plasminogen activator had a mol wt of about 50,000 by zymography. The plasminogen activator adsorbed on Lys-sepharose from the ascites was observed at the 100,000 mol wt position and in the 50,000-100,000 mol wt range on zymography and appeared at the 50,000 mol wt position after treatment by concentration. Its activity was enhanced by trypsin treatment. In other experiments, when incubated homogenate of normal pancreas lacking in zymographic activity was injected intraperitoneally into healthy rats, the recovered fluid displayed lytic zones between the 100,00 and 50,000 mol wt positions. These findings suggest that the ascites contained plasminogen activator, part of which was released by intrapancreatic substances and was present in the precursor form.

Kinetics of the inhibition of free and elastin-bound human pancreatic elastase by alpha 1-proteinase inhibitor and alpha 2-macroglobulin

At pH 8.0 and 25 degrees C alpha 1-proteinase inhibitor and alpha 2-macroglobulin bind human pancreatic elastase with rate constants of 4.7.10(5) M-1.s-1 and 6.4.10(6) M-1.s-1, respectively. The corresponding delay times of elastase inhibition in plasma are 0.4 s and 0.2 s, respectively, indicating that both inhibitors may act as physiological antielastases. Elastin impairs the elastase inhibitory capacity of alpha 1-proteinase inhibitor and alpha 2-macroglobulin. In presence of human elastin, the former behaves like a slow-binding elastase inhibitor, with a rate constant of about 260 M-1.s-1. In contrast, alpha 2-macroglobulin is a fast-binding inhibitor of elastin-bound elastase, but only one of its two sites is functioning in presence of elastin.