Classification and pathogenesis of pancreatitis

The Prognostic Value of Different Levels of Cortisol and High-sensitivity C-reactive Protein in Early Acute Pancreatitis

BACKGROUND

Acute pancreatitis (AP) ranges in severity from mild to severe with high mortality. Severe AP, similar to other critical illnesses, is associated with changes in cortisol level. Early increase of high-sensitivity C-reactive protein (hs-CRP) as an inflammatory marker could be an indicator of AP progression. We aimed to assess the level of cortisol and hs-CRP on initial diagnosis of AP and identify their prognostic value.

METHODS

This case-control study included patients with AP and a control group of healthy subjects. Laboratory tests such as liver profile, kidney functions, blood picture, lactate dehydrogenase, blood glucose, and lipogram were evaluated, the severity of AP was determined, the duration of hospitalization, complications, and outcomes were identified, and the serum levels of cortisol and hs-CRP were assessed.

RESULTS

There were 90 patients with AP and 60 controls with a higher percent of females in both groups. Serum cortisol and hs-CRP were significantly higher in AP relative to controls and were higher in severe AP relative to mild AP. Significant positive correlation was present between high cortisol and severity of AP (r=0.520 and p<0.001) and negatively with pancreatic necrosis (r= - 0.303 and p= 0.007) and morality (r= - 0.432, p= 0.005) while hs-CRP did not show significant correlation.

CONCLUSIONS

Different levels of serum cortisol in early AP should be considered on initial diagnosis. High cortisol level was a good prognostic indicator for AP with low mortality. This could have further implications on the appropriate initiation of steroid therapy to prevent necrotizing pancreatitis and lower the mortality. Meanwhile, hs-CRP has a low prognostic value in early AP.

Impact of the etiology and Vitamin D receptor TaqI rs731236 gene polymorphism on the severity of acute pancreatitis

BACKGROUND/PURPOSE

This work aimed to assess the impact of different etiologies of acute pancreatitis (AP) and vitamin D receptor (VDR) TaqI rs731236 gene polymorphism on the severity of AP.

METHODS

This case-control study included 70 patients with AP and 40 healthy controls. Etiologies of AP were identified by imaging, ANA, cytomegalovirus (CMV) IgM, coxsackie B virus IgM, and IgG4. Genotyping of VDR TaqI rs731236 polymorphism, Laboratory tests and severity scores using Ranson, BISAP, Atlanta and APACHE II scores were determined.

RESULTS

The age in AP patients was 36.03 ± 10.76, and females were 85.7%. The etiologies of AP were as follows: biliary (51.4%), coxsackievirus (22.9%), autoimmune (14.3%), post-ERCP (8.6%) and 2.9% were idiopathic. The TT genotype of VDR polymorphism was significantly more common in AP than control (P = .001) and allele T dominated in AP group (OR = 2; 95% CI: 0.665-5.64). Most cases showed low severity scores with significant differences among etiologies and VDR genotypes. Biliary pancreatitis showed highest percentages of severe AP. However, etiologies and VDR polymorphism were not predictors of severity.

CONCLUSION

Etiology of AP could have impact on the disease severity. VDR gene polymorphism increases the risk of AP. Neither the etiology nor VDR gene polymorphism could predict AP severity.

Role of CCL-2, CCR-2 and CCR-4 in cerulein-induced acute pancreatitis and pancreatitis-associated lung injury

BACKGROUND AND AIMS

Acute pancreatitis is an inflammatory process of variable severity. Leucocytes are thought to play a key role in the development of pancreatitis and pancreatitis-associated lung injury. The interactions between inflammatory cells and their mediators are crucial for determining tissue damage. Monocyte chemoattractant protein-1 (or CCL-2), CCR-2 and CCR-4 are chemokines and chemokine receptors involved in leucocyte trafficking. The aim of the study was to evaluate the role of the CCL-2, CCR-2 and CCR-4 chemokine receptors in the pathogenesis of cerulein-induced pancreatitis and pancreatitis-associated lung injury. To address the role of CCL-2, CCR-2 and CCR-4 that attracts leucocytes cells in inflamed tissues, pancreatitis was induced by administering supramaximal doses of cerulein in mice that do not express CCL-2, CCR-2 or CCR-4.

METHODS

The severity of pancreatitis was measured by serum amylase, pancreatic oedema and acinar cell necrosis. Lung injury was quantitated by evaluating lung microvascular permeability and lung myeloperoxidase activity. Chemokine and chemokine-receptor expression were quantitated by real-time PCR. The nature of inflammatory cells invading the pancreas and lungs was studied by immunostaining.

RESULTS

The authors have found that pancreas CCL-2 and CCR-2 levels rise during pancreatitis. Both pancreatitis and the associated lung injury are blunted, but not completely prevented, in mice deficient in CCL-2, whereas the deficiency in either CCR-2 or CCR-4 does not reduce the severity of both the pancreatitis and the lung injury. The amounts of neutrophils and monocyte/macrophages (MOMA)-2 cells were significantly lower in mice deficient in CCL-2 compared with their sufficient littermates.

CONCLUSIONS

These results suggest that CCL-2 plays a key role in pancreatitis by modulating the infiltration by neutrophils and MOMA-2 cells, and that its deficiency may improve the outcome of the disease.

Growth factor mediated signaling in pancreatic pathogenesis

Functionally, the pancreas consists of two types of tissues: exocrine and endocrine. Exocrine pancreatic disorders mainly involve acute and chronic pancreatitis. Acute pancreatitis typically is benign, while chronic pancreatitis is considered a risk factor for developing pancreatic cancer. Pancreatic carcinoma is the fourth leading cause of cancer related deaths worldwide. Most pancreatic cancers develop in the exocrine tissues. Endocrine pancreatic tumors are more uncommon, and typically are less aggressive than exocrine tumors. However, the endocrine pancreatic disorder, diabetes, is a dominant cause of morbidity and mortality. Importantly, different growth factors and their receptors play critical roles in pancreatic pathogenesis. Hence, an improved understanding of how various growth factors affect pancreatitis and pancreatic carcinoma is necessary to determine appropriate treatment. This chapter describes the role of different growth factors such as vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF), platelet derived growth factor (PDGF), fibroblast growth factor (FGF), epidermal growth factor (EGF), and transforming growth factor (TGF) in various pancreatic pathophysiologies. Finally, the crosstalk between different growth factor axes and their respective signaling mechanisms, which are involved in pancreatitis and pancreatic carcinoma, are also discussed.

The revised Japanese clinical diagnostic criteria for chronic pancreatitis

In Japan, we are now using the clinical diagnostic criteria for chronic pancreatitis (CP) that were revised in 2001 to add the findings of magnetic resonance cholangiopancreatography to the criteria compiled by the Japan Pancreas Society (JPS) in 1995. Because the current criteria are set for diagnosing advanced CP, they are unlikely to improve patients' prognoses. In addition, they seem unsuitable for current clinical practice because exocrine pancreatic function tests, which have become obsolete in Japan, are included in the diagnostic factors. For these reasons, the Research Committee on Intractable Pancreatic Diseases supported by the Ministry of Health, Labour and Welfare of Japan, the JPS and the Japanese Society of Gastroenterology have revised the criteria. The revised criteria are unique in that they contain an introduction to the concept of early CP. It is a challenge aimed at improvement of the long-term prognosis of CP patients by early diagnosis and therapeutic intervention in this disease. We need to determine and clarify the clinico-pathological outcome of early CP by a prospective long-term follow-up of the patients in this category.

Clinical outcomes in patients with ICU-related pancreatitis

AIM: To identify risk factors predictive of intensive care unit (ICU) mortality in patients with ventilator-related pancreatitis. The clinical outcomes of patients with ventilator-related pancreatitis were compared with those of patients with pancreatitis-related respiratory failure as well as controls.

METHODS: One hundred and forty-eight patients with respiratory failure requiring mechanical ventilation and concomitant acute pancreatitis were identified from a prospectively collected dataset of 9108 consecutive patients admitted with respiratory failure over a period of five years. Sixty patients met the criteria for ventilator-related pancreatitis, and 88 (control patients), for pancreatitis-related respiratory failure.

RESULTS: Mortality rate in ventilator-related pancreatitis was comparable to that in ICU patients without pancreatitis by case-control methodology (P = 0.544). Multivariate logistic regression analysis identified low PaO₂/FiO₂ (OR: 1.032, 95% CI: 1.006-1.059, P = 0.016) as an independent risk factor for mortality in patients with ventilator-related pancreatitis. The mortality rate in patients with ventilator-related pancreatitis was lower than that in patients with acute pancreatitis-related respiratory failure (P < 0.001).

CONCLUSION: We found that low PaO₂/FiO₂ was an independent clinical parameter predictive of ICU mortality in patients with ventilator-related pancreatitis.

Acute pancreatitis markedly accelerates pancreatic cancer progression in mice expressing oncogenic Kras

Chronic pancreatitis increases by 16-fold the risk of developing pancreatic ductal adenocarcinoma (PDAC), one of the deadliest human cancers. It also appears to accelerate cancer progression in genetically engineered mouse models. We now report that in a mouse model where oncogenic Kras is activated in all pancreatic cell types, two brief episodes of acute pancreatitis caused rapid PanIN progression and accelerated pancreatic cancer development. Thus, a brief inflammatory insult to the pancreas, when occurring in the context of oncogenic Kras(G12D), can initiate a cascade of events that dramatically enhances the risk for pancreatic malignant transformation.

A new venomous scorpion responsible for severe envenomation in Argentina: Tityus confluens

In Argentina the scorpions of medical importance belong to the genus Tityus (T.), particularly the species T. trivittatus, the only scorpion whose sting is recognized to be associated with severe human envenoming and death. This genus is distributed from the north of the Patagonian region to the center and some provinces in the north of the country. During the period 2003-2006 four children died following scorpion stings, of which one was certainly and three were probably by T. confluens. In 2006, in the province of Tucumán, a girl died by scorpion envenoming and the scorpion responsible for the death, found in her shoe, was T. confluens. We thus studied the toxicity of venom gland homogenates from T. confluens from the provinces of Jujuy and Catamarca, and of crude venom from specimens from Catamarca and the province of La Rioja. The lethal potencies of the telson homogenates were 7.0 and 18.6microg/g for Jujuy and Catamarca, respectively, while the lethal potency of the crude venom was 0.7microg/g. Injected mice showed generalized congestion and hepatic lesions. Pancreatic damage was observed in some animals. Lungs showed congestion and foci of hemorrhage and mild edema. The heart showed injury in the muscular fibers. The venom showed high reactivity against anti-T. trivittatus antivenom and against two anti-T. serrulatus antivenoms. The anti-T. trivittatus antivenom neutralized the lethal activity of T. confluens venom. In addition, the venom reacted very slightly against an anti-Centruroides antivenom. Therefore, the stings of this scorpion must be considered of risk for humans to the same degree as the stings of T. trivittatus.

Early diagnosis and prediction of severity in acute pancreatitis using the urine trypsinogen-2 dipstick test: a prospective study

AIM

To evaluate the use of the trypsinogen-2 dipstick (Actim Pancreatitis) test for early diagnosis and prediction of severity in acute pancreatitis (AP).

METHODS

Ninety-two patients with AP were included in this study. The control group was 25 patients who had acute abdominal pain from non-pancreatic causes. Urine trypsinogen-2 dipstick test (UTDT) and conventional diagnostic tests were performed in all patients. Patients were divided by the Atlanta classification into two groups as having mild or severe pancreatitis.

RESULTS

UTDT was positive in 87 (94.6%) of the AP patients and in two (8%) controls (P < 0.05). Positive UTDT was found in 61 (92.4%) of 66 (71.7%) patients with mild pancreatitis and in all (100%) of the 26 (28.3%) with severe pancreatitis (P > 0.05). UTDT positivity lasted longer in severe pancreatitis compared with that in mild pancreatitis (6.2 +/- 2.5 d vs 2.0 +/- 1.43 d, P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of UTDT were 91%, 72%, 96.6%, 70.4%, 3.4 and 0.1, respectively.

CONCLUSION

UTDT is a simple, rapid and reliable method for use on admission. It has high specificity and low NLR for early diagnosis and prediction of severity in AP. However, its relatively low NPV does not allow trypsinogen-2 dipstick test to be a stand-alone tool for diagnosis of acute pancreatitis; the use of other conventional diagnostic tools remains a requirement.

Early diagnosis and prediction of severity in acute pancreatitis using the urine trypsinogen-2 dipstick test: a prospective study

AIM

To evaluate the use of the trypsinogen-2 dipstick (Actim Pancreatitis) test for early diagnosis and prediction of severity in acute pancreatitis (AP).

METHODS

Ninety-two patients with AP were included in this study. The control group was 25 patients who had acute abdominal pain from non-pancreatic causes. Urine trypsinogen-2 dipstick test (UTDT) and conventional diagnostic tests were performed in all patients. Patients were divided by the Atlanta classification into two groups as having mild or severe pancreatitis.

RESULTS

UTDT was positive in 87 (94.6%) of the AP patients and in two (8%) controls (P < 0.05). Positive UTDT was found in 61 (92.4%) of 66 (71.7%) patients with mild pancreatitis and in all (100%) of the 26 (28.3%) with severe pancreatitis (P > 0.05). UTDT positivity lasted longer in severe pancreatitis compared with that in mild pancreatitis (6.2 +/- 2.5 d vs 2.0 +/- 1.43 d, P < 0.05). The sensitivity, specificity, positive predictive value, negative predictive value (NPV), positive likelihood ratio (PLR) and negative likelihood ratio (NLR) of UTDT were 91%, 72%, 96.6%, 70.4%, 3.4 and 0.1, respectively.

CONCLUSION

UTDT is a simple, rapid and reliable method for use on admission. It has high specificity and low NLR for early diagnosis and prediction of severity in AP. However, its relatively low NPV does not allow trypsinogen-2 dipstick test to be a stand-alone tool for diagnosis of acute pancreatitis; the use of other conventional diagnostic tools remains a requirement.

Adrenomedullin reduces the severity of cerulein-induced acute pancreatitis

We investigated the effect of Adrenomedullin (AM) on cerulein-induced acute pancreatitis in rats. AM treatment (100 ng/kg per rat, subcutaneous) after one hour of cerulein injection reduced the plasma amylase levels, pancreatic weight, pancreatic malondialdehyde (MDA) levels, and the severity of the lesions microscopically. These data suggest that AM has a protective effect on cerulein-induced acute pancreatitis. These could be due to anti-inflammatory properties of AM, inhibition of proinflammatory cytokine secretion, reducing the endothelial permeability increased by reactive oxygen species, endotoxins or cytokines.

PPAR-gamma knockout in pancreatic epithelial cells abolishes the inhibitory effect of rosiglitazone on caerulein-induced acute pancreatitis

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists, such as the thiazolidinediones (TZDs), decrease acute inflammation in both pancreatic cell lines and mouse models of acute pancreatitis. Since PPAR-gamma agonists have been shown to exert some of their actions independent of PPAR-gamma, the role of PPAR-gamma in pancreatic inflammation has not been directly tested. Furthermore, the differential role of PPAR-gamma in endodermal derivatives (acini, ductal cells, and islets) as opposed to the endothelial or inflammatory cells is unknown. To determine whether the effects of a TZD, rosiglitazone, on caerulein-induced acute pancreatitis are dependent on PPAR-gamma in the endodermal derivatives, we created a cell-type specific knock out of PPAR-gamma in pancreatic acini, ducts, and islets. PPAR-gamma knockout animals show a greater response in some inflammatory genes after caerulein challenge. The anti-inflammatory effect of rosiglitazone on edema, macrophage infiltration, and expression of the proinflammatory cytokines is significantly decreased in pancreata of the knockout animals compared with control animals. However, rosiglitazone retains its effect in the lungs of the pancreatic-specific PPAR-gamma knockout animals, likely due to direct anti-inflammatory effect on lung parenchyma. These data show that the PPAR-gamma in the pancreatic epithelia and islets is important in suppressing inflammation and is required for the anti-inflammatory effects of TZDs in acute pancreatitis.

IFN-gamma protects cerulein-induced acute pancreatitis by repressing NF-kappa B activation

We explored the pathophysiological roles of IFN-gamma in cerulein-induced acute pancreatitis. In wild-type (WT) mice, cerulein injection caused acute pancreatitis as evidenced by increased serum amylase levels and pathological changes such as interstitial edema, vacuolization, acinar cell necrosis, and neutrophil infiltration in pancreas. Concomitantly, cerulein treatment augmented intrapancreatic gene expression of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, cyclooxygenase-2 (COX-2), and IFN-gamma in WT mice. In situ hybridization combined with immunofluorescence analyses demonstrated that infiltrating neutrophils expressed IFN-gamma mRNA. Unexpectedly, IFN-gamma(-/-) mice exhibited exacerbated cerulein-induced pancreatic injury, with enhanced neutrophil recruitment. Moreover, intrapancreatic gene expression of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, and COX-2 were significantly exaggerated in IFN-gamma(-/-) mice, compared with WT mice. Cerulein activated NF-kappaB, an indispensable transcription factor for gene transcription of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, and COX-2, in pancreas of cerulein-treated WT mice as evidenced by the increases in nuclear amount and DNA-binding activity of NF-kappaB p65. In comparison with WT mice, IFN-gamma(-/-) mice exhibited exaggerated and prolonged NF-kappaB activation, probably due to reduced acetylation of Stat1, a main signal transducer of IFN-gamma, because acetylated Stat1 can inhibit NF-kappaB activation. Indeed, IFN-gamma acetylated Stat1 and reciprocally reduced NF-kappaB activation and COX-2 expression in neutrophils. Finally, even when administered 4 h after the first cerulein injection, IFN-gamma remarkably attenuated acute pancreatitis in both WT and IFN-gamma(-/-) mice, with reduced NF-kappaB activation and COX-2 expression. Thus, IFN-gamma can have anti-inflammatory effects on acute pancreatitis by depressing the proinflammatory consequences of NF-kappaB activation.

Acute pancreatitis

Acute pancreatitis is characterized by the occurrence of necroinflammatory changes in the pancreas. Three types of necrosis may be distinguished: (1) interstitial tissue necrosis, which subsequently may also involve acinar and ductal cells, (2) ductal necrosis, and (3) acinar necrosis. The first type of necrosis is autodigestive in nature and is typical of the most common forms of acute pancreatitis, which are associated with alcohol, bile duct disease, metabolic conditions, and other rare factors. Clinically, these types of pancreatitis may be either mild or severe (Atlanta classification). The mild form is also known as edematous pancreatitis, because there is edematous swelling of the pancreas combined with tiny foci of interstitial (fat) necrosis. Severe or necrotizing pancreatitis shows large areas of often hemorrhagic necrosis of the pancreatic and particularly the peripancreatic tissue. The ductal type of necrosis is rare and may be seen in pancreatitis associated with prolonged circulatory failure. The acinar type of necrosis is caused by infectious agents. Complications of acute pancreatitis, such as pseudocyst, bleeding, and infection, determine the course of the disease.

O mosaico patogênico da pancreatite aguda grave

A pancreatite aguda tem sido alvo de grandes discussões que vão desde o entendimento de sua fisiopatologia até a investigação de novas modalidades terapêuticas. Reconhece-se que a necrose pancreática e a falência orgânica múltipla - mormente associadas à infecção - representam os principais fatores determinantes da evolução para o óbito, mas, apesar dos grandes avanços em seu estudo, a doença permanece como um desafio para o clínico e o cirurgião. Deste modo, um melhor conhecimento dos mecanismos envolvidos em sua fisiopatologia pode ser a chave para um tratamento mais eficaz, principalmente em relação às formas graves, cuja letalidade ainda encontra-se substancialmente elevada. Baseado nestas considerações, o presente trabalho tem por objetivo a revisão bibliográfica da fisiopatologia, dos fatores patogênicos envolvidos na história natural da pancreatite aguda grave e dos eventos associados à síndrome da resposta inflamatória sistêmica e à sepse, esboçando-se assim o mosaico patogênico desta importante condição.

Histophatological changes and inflammatory response induced by Tityus discrepans scorpion venom in rams

Anesthetized rams envenomed s.c. with 40 microg/kg Tityus discrepans scorpion venom developed fasciculation, hypothermia, polyuria, pulmonary wet rales, tachypnea, respiratory distress and arrhythmia. Rams developed a cascade of inflammation reactions, characterized by activation of macrophages, fibroblasts and neutrophils, neutrophil infiltration and aggregation, vasculitis, arteritis and abundant fibrin deposition. At the inoculation site, venom was detected by immunohistochemistry in the extra cellular matrix, lymphatic vessels' and venules' lumen, inside macrophages and surrounding nerves. Extra cellular matrix was degraded at the inoculation site perhaps by activated neutrophils. Envenoming produced hepatocytes with Mallory body-like vacuoles which may be due to the increased plasmatic levels of TNF-alpha and IL6. Venom produced degranulation and vacuolization of acinary cells as well as interstitial swelling and necrosis. Necrosis of the Langerhan's islets occurred occasionally. Lungs showed the most deleterious effects developing wall collapse and necrosis, diffuse injury of the alveolar capillary barrier, interstitial and alveolar fibrin deposits with strong neutrophil infiltration. Massive infiltration of lymphocytes and macrophage occurred in the intestinal submucose, to the point that it modified villi and intestinal folding morphology. Envenomation developed a marked leukocyte aggregation surrounding nerves at the inoculation site. This study reveals that beyond its neurotoxicity, Tityus venom produces a severe and widespread inflammatory syndrome, expressed as histopathological changes at the site of inoculation, as well as in remote organs such as pancreas, lungs, intestine and liver. Our results suggest that not all remote targets are directly affected by the venom but that, as proposed earlier, are modified by inflammation by products produced elsewhere.

Role of Toll-like receptor 4 on pancreatic and pulmonary injury in a mice model of acute pancreatitis associated with endotoxemia

OBJECTIVE

Infection of pancreatic necrosis is a severe complication of acute pancreatitis. Because Toll-like receptor 4 (TLR4) has been identified as a receptor necessary to transduct the signal of bacteria-derived lipopolysaccharide into cells, we investigated the role of TLR4 on pancreatic and pulmonary injury in acute pancreatitis and acute pancreatitis associated with endotoxemia in wild-type and TLR4-deficient mice.

DESIGN

Laboratory investigation.

SETTING

University laboratory.

SUBJECTS

Heterozygous TLR4 mice.

INTERVENTIONS

Mice were injected intraperitoneally with a supramaximal dose of cerulein each hour for 10 hrs. To mimic infection, additional groups of mice were injected with lipopolysaccharide in the presence or absence of cerulein injections.

MEASUREMENTS AND MAIN RESULTS

The severity of acute pancreatitis was assessed by serum amylase activity, pancreatic edema, acinar cell necrosis, and pancreas myeloperoxidase activity. Lung injury was quantitated by lung microvascular permeability and lung myeloperoxidase activity. Injections of cerulein induced an edematous pancreatitis that was of similar severity in wild-type and TLR4-deficient mice. Lipopolysaccharide alone had no toxic effect on pancreas and lungs and did not worsen the pancreatic injury induced by cerulein in wild-type and TRL4-deficient mice. In contrast, lipopolysaccharide worsened pancreatitis-associated lung injury, and the deficiency in TLR4 fully prevented this aggravation.

CONCLUSIONS

TLR4 may not play a role in the pancreatitis-associated lung injury but participates in the pulmonary injury mediated by endotoxemia.

Smoking, coffee, and pancreatitis

OBJECTIVES

We studied relationships of cigarette smoking and coffee drinking to risk of pancreatitis.

METHODS

This was a cohort study among 129,000 prepaid health plan members who supplied data about demographics and habits in 1978-85. Among 439 persons subsequently hospitalized for pancreatitis, probable etiologic associations were cholelithiasis (168/439 = 38%), alcohol (125/439 = 29%), idiopathic (110/430 = 25%), and miscellaneous (36/439 = 8%). Cox proportional hazards models with seven covariates (including alcohol intake) yielded relative risk estimates for smoking and coffee use.

RESULTS

Increasing smoking was strongly related to increased risk of alcohol-associated pancreatitis, less related to idiopathic pancreatitis, and unrelated to gallstone-associated pancreatitis. Relative risks (95% confidence intervals, CI) of one pack per day (vs never) smokers for pancreatitis groups were: alcohol = 4.9 (2.2-11.2, p < 0.001), idiopathic = 3.1 (1.4-7.2, p < 0.01), and gallstone = 1.3 (0.6-3.1). The relationship of smoking to alcohol-associated pancreatitis was consistent in sex and race subsets. Drinking coffee, but not tea, was weakly inversely related to risk only of alcohol-associated pancreatitis, with relative risk (95% CI) per cup per day = 0.85 (0.77-0.95; p= 0.003). Male sex, black ethnicity, and lower-educational attainment were other predictors of alcohol-associated pancreatitis.

CONCLUSIONS

Cigarette smoking is an independent risk factor for alcohol-associated and idiopathic pancreatitis. Coffee drinking is associated with reduced risk of alcohol-associated pancreatitis. The data are compatible with the hypotheses that smoking may be toxic to the pancreas or may potentiate other pancreatic toxins while some ingredient in coffee may have a modulating effect.

Approach to idiopathic recurrent pancreatitis

Acute pancreatitis is caused by acute or chronic alcohol intake or choledocholithiasis in approximately 80% of cases. In the absence of alcohol abuse or gallstones, a variety of established and putative factors must be considered, any of which can cause a single or recurrent attacks of acute pancreatitis. When the underlying cause eludes detection following an initial thorough search and leads to a second attack, the term idiopathic acute recurrent pancreatitis (IARP) is applied. This article discusses IARP and its work-up.

Role of macrophage inflammatory peptide-2 in cerulein-induced acute pancreatitis and pancreatitis-associated lung injury

Acute pancreatitis is an inflammatory process of variable severity, and leukocytes are thought to play a key role in the development of pancreatitis and pancreatitis-associated lung injury. The effects of mediators released by these inflammatory cells may induce tissue damage. The aim of our study was to evaluate the role of the chemokine, macrophage inflammatory protein-2 (MIP-2), in the pathogenesis of cerulein-induced pancreatitis and pancreatitis-associated lung injury. The severity of pancreatitis was measured by serum amylase, pancreatic edema, acinar cell necrosis, and myeloperoxidase activity. Lung injury was quantitated by evaluating lung microvascular permeability and lung myeloperoxidase activity. To determine the role of MIP-2 in the pathophysiology of the disease, anti-MIP-2 antibody was administered either 1 hour before or 2 hours after the start of cerulein administration. MIP-2 concentrations increased in serum, pancreas, and lung tissues in mice treated with cerulein. Anti-MIP-2 antibody administrated either before or after cerulein partially protected against pancreas and lung injury. These results show that MIP-2 plays a key role in the pathophysiology of acute pancreatitis and that MIP-2 blockade may improve the outcome of the disease.

Acute and chronic pancreatitis

Acute pancreatitis has multiple causes, an unpredictable course, and myriad complications. The diagnosis relies on a combination of history, physical examination, serologic markers, and radiologic findings. The mainstay of therapy includes aggressive hydration, maintenance of NPO, and adequate analgesia with narcotics. Antibiotic and nutritional support with total parenteral nutrition should be used when appropriate.

Acute pancreatitis results in induction of heat shock proteins 70 and 27 and heat shock factor-1

Heat shock proteins (HSPs) 70 and 27 are stress-responsive proteins that are important for cell survival after injury; the expression of these HSPs is regulated primarily by the transcription factor heat shock factor-1 (HSF-1). The purpose of this study was to determine the effect of acute pancreatitis on pancreatic HSPs (70, 27, 60, and 90) expression and to assess potential mechanisms for HSP induction using a murine model of cerulein-induced pancreatitis. We found an increase of both HSP70 and HSP27 levels with expression noted throughout the pancreas after induction of pancreatitis. HSP60 and HSP90 levels were constitutively expressed in the pancreas and did not significantly change with acute pancreatitis. HSF-1 DNA binding activity increased in accordance with increased HSP expression. We conclude that acute pancreatitis results in a marked increase in the expression of HSP70 and HSP27. Furthermore, the induction of HSP70 and HSP27 expression was associated with a concomitant increase in HSF-1 binding activity. The increased expression of both HSP70 and HSP27 noted with pancreatic inflammation may confer a protective effect for the remaining acini after acute pancreatitis.

Etiology and pathogenesis of acute pancreatitis: current concepts

Acute pancreatitis is a disorder that has numerous causes and an obscure pathogenesis. Bile duct stones and alcohol abuse together account for about 80% of acute pancreatitis. Most episodes of biliary pancreatitis are associated with transient impaction of the stone in the ampulla (that causes obstruction of the pancreatic duct, with ductal hypertension) or passage of the stone though and into the duodenum. Other causes of acute pancreatitis are various toxins, drugs, other obstructive causes (such as malignancy or fibrotic sphincter of Oddi), metabolic abnormalities, trauma, ischemia, infection, autoimmune diseases, etc. In 10% of cases of acute pancreatitis, no underlying cause can be identified; this is idiopathic pancreatitis. Occult biliary microlithiasis may be the cause of two thirds of the cases of "idiopathic" acute pancreatitis. Intra-acinar activation of trypsinogen plays a central role in the pathogenesis of acute pancreatitis, resulting in subsequent activation of other proteases causing the subsequent cell damage. Ischemia/reperfusion injury is increasingly recognized as a common and important mechanism in the pathogenesis of acute pancreatitis and especially in the progression from mild edematous to severe necrotizing form. Increased intracellular calcium concentration also mediates acinar cell damage. Oxygen-derived free radicals and many cytokines (e.g., interleukin [IL]-1, IL-6, IL-8, tumor necrosis factor-alpha, platelet activating factor) are considered to be principal mediators in the transformation of acute pancreatitis from a local inflammatory process into a multiorgan illness.

Biliary pancreatitis: a review. Emphasizing appropriate endoscopic intervention

Gallstones are a common cause of acute pancreatitis. This article reviews acute biliary pancreatitis and includes natural history, noting the serious nature of some cases; pathogenesis, identifying transient obstruction as the primary pathogenetic event; diagnosis, including biochemical parameters and imaging; assessment of severity, underlining the importance of early prognostic signs, organ failure, and local complications; and management. Management is reviewed in detail, giving a historical perspective to the role of surgery, highlighting the role of endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy and paying particular attention to the four prospective randomized clinical trials in suggesting which patients are most likely to benefit from early endoscopic evaluation and therapy. Also discussed are additional clinical situations related to biliary pancreatitis in which endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy play a role. Finally, a suggested endoscopic approach to acute biliary pancreatitis is presented along with an algorithm incorporating severity stratification, principles of endoscopic intervention, and concepts of sterile and infected pancreatic necrosis.

Toxic epidermal necrolysis in a burn patient complicated by acute pancreatitis

This report concerns a previously healthy patient who presented with 8% total body surface area burn wounds to his face and neck. Even though his burn wounds healed quickly, his course was complicated by the development of toxic epidermal necrolysis affecting 60% total body surface area due to a drug reaction. During the recovery period he subsequently developed jaundice and pancreatitis -- a rare and interesting course that is not well described in the literature.

Role of macrophage overactivation in the development of acute pancreatic injury in rats

BACKGROUND

An increase in systemic inflammatory mediators from stimulated leucocytes and macrophages has been noted during acute pancreatitis. The role of cytolytic inflammatory macrophages and potential mechanisms in the development of acute pancreatic injury and endothelial barrier dysfunction are less well defined.

METHODS

Rats were challenged by an intraperitoneal injection of cytolytic or non-cytolytic inflammatory macrophage stimulators at various concentrations. The effects of oxygen free radicals, prostaglandin and extracellular calcium influx on macrophage-associated pancreatic endothelial compromise, measured by pancreatic intravascular plasma volume, pancreatic interstitial fluid volume, and the pancreatic extravascular human serum albumin distribution volume, were explored.

RESULTS

Zymosan-induced overactivation of cytolytic inflammatory macrophages resulted in the development of acute pancreatic endothelial dysfunction in a dose- and time-dependent pattern. An increase in pancreatic water content and interstitial fluid volume was observed following a higher dose (0.5 mg/g) of concanavalin A without alteration in plasma lipase level, while thioglycollate medium did not compromise pancreatic endothelial barrier function. Oxygen free radicals, but also prostaglandins and extracellular calcium influx, seemed to be involved in macrophage overactivation-induced pancreatic injury.

CONCLUSION

Overactivation of cytolytic macrophages plays a role in the pathogenesis of pancreatic injury by initiating the development of endothelial barrier dysfunction. Multiple inflammatory mediators from overactivated macrophages act as intercellular signals between macrophages and the endothelium during acute pancreatic injury.

The potential role of Clostridium perfringens alpha toxin in the pathogenesis of acute pancreatitis

BACKGROUND

Clostridium perfringens is a bowel commensal that can colonise the biliary tract. It produces the alpha toxin (phospholipase C), which can induce spontaneous tissue necrosis.

AIMS

To investigate whether there is any evidence that Clostridium perfringens alpha toxin can be detected in acute pancreatitis.

METHODS

Serum samples from 21 patients with acute pancreatitis and 22 controls were assayed for C perfringens phospholipase C as well as anti-phospholipase C IgG and IgM; IgG and IgM anti-toxins were measured by enzyme linked immunosorbent assay.

RESULTS

In normal healthy controls there is a very high level of natural anti-toxin of both the IgG and IgM class. Of the 21 patients with acute pancreatitis alpha toxin was detected in five (23.8%). Levels of both IgG and IgM anti-toxin were significantly reduced in acute pancreatitis.

CONCLUSIONS

The results suggest that there is an abnormality of the immune status to C perfringens alpha toxin in patients with acute pancreatitis. This may be the result of a release of alpha toxin, although it is difficult to state whether this is a primary or secondary phenomenon in these patients. These preliminary results merit further investigation.

Washington University experience with extracorporeal shock-wave lithotripsy of pancreatic duct calculi

OBJECTIVES

To ascertain the effectiveness and safety of extracorporeal shock-wave lithotripsy (ESWL) for pancreatic calculi.

METHODS

Fourteen ESWL treatments were performed in 12 patients with chronic pancreatitis.

RESULTS

Fragmentation was perceptible after 13 of 14 treatments. Subsequent endoscopic manipulation resulted in complete extraction, partial extraction, and failed extraction of the fragments after 7, 4, and 2 of the ESWL treatments, respectively. No complications occurred and no patient had pancreatitis following ESWL. At a median follow-up of 19 to 22 months, 4 patients have had complete relief of symptoms, 4 have had a decrease in both severity and frequency of pain, and 4 have had no improvement.

CONCLUSIONS

ESWL is a safe and useful noninvasive adjunct in the treatment of patients with pancreatic duct calculi.

Role of nitric oxide in lung injury associated with experimental acute pancreatitis

This study evaluated the effect of varying the synthesis of nitric oxide with sodium nitroprusside or N-nitro-L-arginine methyl ester (L-NAME) in a pancreatitis-lung injury model. Rats (n = 45) were randomized to control or caerulein-induced pancreatitis groups, treated with saline, sodium nitroprusside (0.4 micrograms/kg) or L-NAME (10 mg/kg). Myeloperoxidase activity was used as a measure of neutrophil infiltration. Wet to dry (W:D) lung weight and bronchoalveolar lavage (BAL) protein concentrations were used to assess vascular leakage. Pancreatitis was shown to induce pulmonary neutrophil influx: mean(s.e.m.) myeloperoxidase activity 6.79(0.5) units/g in caerulein-treated animals versus 2.08(0.5) units/g in controls (P < 0.001). Animals with pancreatitis showed increased microvascular leakage compared with controls (mean(s.e.m.) W:D lung weight 7.01(0.5) versus 2.85(0.2), P < 0.001; BAL protein concentration 2539(222) versus 347(32) micrograms/ml, P < 0.001). Compared with the saline-treated pancreatitis group, these changes were reduced by sodium nitroprusside (mean(s.e.m.) myeloperoxidase activity to 2.5(0.4) units/g, P < 0.001; W:D lung weight to 3.8(0.37), P < 0.001; BAL protein concentration 1389(182) micrograms/ml, P < 0.05). L-NAME exacerbated the pancreatitis-induced pulmonary oedema (W:D lung weight increased to 11.96(0.6), P < 0.001), protein leakage (BAL protein concentration rose to 3707(309) micrograms/ml, P < 0.05) and neutrophil infiltration (myeloperoxidase activity increased to 9.01(0.3) units/g, P < 0.05). These data suggest that, in vivo, nitric oxide inhibits pancreatitis-induced lung injury, possibly in part by inhibiting pulmonary neutrophil influx.

Immunocytochemical localization of elastase 1 in human pancreas

By light and electron microscopic immunocytochemistry the distribution is described of human pancreatic elastase 1 (E1) during ontogenesis, in adults, in cases of acute and chronic pancreatitis, acute pancreatic ischaemia as well as pancreatic tumours. E1-positive cells were first detected in ductal sprouts in the 14th gestational week. Complete acini expressing E1 could be found from the 17th to the 20th week of gestation onwards. Scattered distinct E1-positive epithelia could be found in the ducts of fetal and adult pancreas. By immunoelectron microscopy, E1 was localized in rough endoplasmic reticulum, condensing vacuoles, zymogen granules of acinar epithelia and in acinar lumina. E1 appeared to be distributed homogeneously in zymogen granules. As specific markers of acinar cells, both monoclonal antibodies under study identified heterotopic pancreatic acini in peribiliar glands of the liver and also helped to visualize different damage patterns in pancreatitis. The acinar epithelia surrounding acute lipolytic necroses initially reacted more intensely with the E1-antibodies than undamaged pancreatic tissue. In acute ischaemia, acinar cells which are dissociated from intercalated ducts lost their immunocytochemical reactivity for E1. Pancreatic parenchyma involved in advanced acute pancreatitis as well as in chronic inflammation was detected only weakly by both E1-antibodies. However, atrophic lobules in post-inflammatory scars were stained more intensely by the E1-antibodies than normal parenchyma. Pancreatic tumours (adenomas, adenocarcinomas, solid-cystic tumours and islet cell tumours) were not labelled by these antibodies.

A case of intraduodenal diverticulum imitating choledochocele

An intraduodenal diverticulum in 54 year old woman which caused alcalculous cholecystitis and pancreatitis is described. The diverticulum was missed at the first operation, performed for acute cholecystitis. Before the second it was interpreted as a pancreatic cyst. At the second intervention, the cyst wall was excised through a duodenotomy. Histological examination of the wall of the diverticulum is crucial for correct diagnosis.

Pancreatic ductal and interstitial pressures in cats with chronic pancreatitis

We investigated the etiology of interstitial hypertension in chronic pancreatitis by examining the relationship between pancreatic ductal and interstitial pressures in cats. The main pancreatic duct was cannulated in the tail of the gland and perfused at 1, 2, or 5 ml/hr, to simulate pancreatic secretion. Intraductal and interstitial pressures were measured in four groups of animals: (1) normal cats; (2) normal cats after acutely narrowing the main duct to 25% of its original diameter; (3) normal cats after encasing the body and tail in a rigid latex capsule; and (4) cats with chronic pancreatitis created by narrowing the main duct five weeks earlier. Duct perfusion increased intraductal pressure in all of the cats, but significantly more in groups 2, 3, and 4 compared to group 1. Pancreatic interstitial pressure was unchanged by duct perfusion in groups 1 and 2, but increased in groups 3 and 4. We concluded that the compliant tissue of the normal pancreas expanded to effectively dissipate the increase in duct pressure associated with duct perfusion. In chronic pancreatitis, the inelastic parenchyma and capsule limited the distensibility of the gland, which resulted in elevated interstitial pressures during duct perfusion.

Influence of the etiology of pancreatitis on the natural history of pancreatic pseudocysts

We reviewed our experience with 90 patients with pancreatic pseudocysts to determine if the cause of pancreatitis influenced the patients' outcome. Acute pancreatitis (AP) occurred in 57 (63%) patients due to alcoholic (n = 15), postoperative (n = 14), biliary (n = 12), and other etiologies (n = 16). Thirty-three (37%) patients had chronic pancreatitis (CP) secondary to alcohol use (n = 27) or other causes (n = 6). Multiple pseudocysts were significantly more frequent in patients with acute alcoholic pancreatitis than in patients with chronic pancreatitis (47% versus 19%, p < 0.05). Spontaneous resolution occurred within 8 weeks in 10 (11%) patients with pseudocysts (AP = 9%, CP = 15%, p = NS). However, no patient with pseudocyst associated with biliary or postoperative pancreatitis underwent spontaneous resolution. Although pseudocysts associated with chronic pancreatitis were smaller in size (8.0 +/- 4.7 versus 5.7 +/- 3.8 cm, p < 0.05), a similar proportion of them required operation compared with AP pseudocysts (56% versus 58%). There were significantly more deaths in patients with postoperative pancreatitis compared with all other groups (29% versus 7%, p < 0.05). The outcome of pseudocysts was similar regardless of size (greater than 6 cm versus less than 6 cm) and presentation (acute versus delayed). Thus, the etiology of pancreatitis was a more important determinant of pseudocyst outcome than pseudocyst size or presentation.

Acute pancreatitis following aortic aneurysm repair: report of three cases

This paper reports three cases of acute pancreatitis that occurred after repair of an abdominal aortic aneurysm. The aneurysms were ruptured in two patients and asymptomatic in one. No patient had biliary disease or history of pancreatitis or alcohol abuse. Two of the patients required operation for drainage and debridement; one died. The etiology and diagnosis are discussed.

Classification of acute pancreatitis

Increased knowledge of the natural history, etiology, morphology, complications and systemic response of the patient to acute pancreatitis has led to a rapid evolution in the classification of acute pancreatitis. It is recommended that the following elements be included in a classification system of acute pancreatitis: 1. A definition of acute pancreatitis and its complications based on CT scan, ultrasound, ERCP, and angiographic and histologic findings. 2. A statement regarding the etiology of the patient's pancreatitis. 3. An assessment of the patient's systemic response to his or her pancreatitis by means of APACHE II and/or Ranson's signs of severity. This system, through the use of ultrasound, CT scan with vascular enhancement, and clinical and laboratory tests, can be utilized to classify patients initially, on the day of hospital admission, with regard to etiology, morphology, and physiologic severity. Later in their hospital course, the complications of pancreatitis, e.g., fluid collections, necrosis, pseudocysts, infected necrosis, abscesses, fistulas, pancreatic, enteric, and cutaneous, pseudoaneurysm, and splenic vein thrombosis, can be added to the classification as modifiers when and if they occur. The process of the development and confirmation of theories of the origin and nature of the cosmos and evolution of concepts regarding the classification of pancreatitis have something in common. Theory generally stimulates experimental observation whose purpose is to test the theory's validity. New theories are generated when experimental observations demonstrate inconsistencies in previously held beliefs. Just as our understanding of the cosmos is undergoing constant change based on new data and new theories, so are our concepts regarding the classification of pancreatitis.

Gallstone pancreatitis

Gallstone pancreatitis is caused by transient obstruction of the ampulla of Vater by a migrating gallstone. Intraglandular activation of pancreatic enzymes occurs (by an unclear mechanism), and their entry into the circulation causes most of the local and systemic events of pancreatitis. The diagnosis is based on history and physical examination, an elevation of serum amylase above 1000 IU/L, and ultrasound and CT scans. Endoscopic retrograde cholangiopancreatography can be used in less certain cases to confirm the presence of common bile duct stones. Because of the absence of an agent that can abort progression of the disease, therapy should consist of adequate resuscitation, nutritional support, and careful monitoring to detect early complications. In patients with mild pancreatitis, surgery usually can be performed within 48 or 72 hours of admission or as soon as symptoms and amylase levels return to normal. For patients with severe disease, endoscopic sphincterotomy is emerging as the therapeutic modality of choice. Elective treatment of the associated biliary disease should be performed during the same hospitalization after the acute phase of the disease has subsided.