Acute pancreatitis is not a cause of chronic pancreatitis in the absence of residual duct strictures

Chronic pancreatitis. The problems of diagnostic criteria

The diagnostic criteria for chronic pancreatitis proposed by the Japan Pancreas Society (JPS) classified chronic pancreatitis into (i) definite; (ii) probable, and (iii) possible chronic pancreatitis, excluding obstructive, inflammatory (autoimmune) and tumor-forming pancreatitis from the definition of chronic pancreatitis. In the JPS Criteria, imaging studies, pancreatic function tests, and histological findings are independent of each other, and thus the diagnosis of chronic pancreatitis is made if one of the criteria is satisfied, regardless of the etiology of the chronic pancreatitis. The current diagnostic criteria for chronic pancreatitis depend on abnormalities of the duct system, such as low bicarbonate output, dilation of main pancreatic duct and duct branches, and calculi in the ducts by imaging studies. We revealed that the difference between reversible and irreversible pancreatitis in experimental animals is dependent on the degree of damage of the duct epithelium where pancreas progenitor cells exist. Thus, chronic pancreatitis diagnosed by the current criteria based on abnormalities of the duct system is irreversible. In contrast, the epithelium of the ducts is usually preserved in obstructive and autoimmune pancreatitis in that both structural and functional changes recover almost completely when the obstruction is removed or the inflammatory changes disappear following steroid administration. Even in chronic pancreatitis defined as irreversible, there must be a reversible stage during its clinical course. There is a need to develop biological markers and/or imaging procedure to detect chronic pancreatitis at its reversible stage.

Chronic pancreatitis: diagnosis, classification, and new genetic developments

The utilization of recent advances in molecular and genomic technologies and progress in pancreatic imaging techniques provided remarkable insight into genetic, environmental, immunologic, and pathobiological factors leading to chronic pancreatitis. Translation of these advances into clinical practice demands a reassessment of current approaches to diagnosis, classification, and staging. We conclude that an adequate pancreatic biopsy must be the gold standard against which all diagnostic approaches are judged. Although computed tomography remains the initial test of choice for the diagnosis of chronic pancreatitis, the roles of endoscopic retrograde pancreatography, endoscopic ultrasonography, and magnetic resonance imaging are considered. Once chronic pancreatitis is diagnosed, proper classification becomes important. Major predisposing risk factors to chronic pancreatitis may be categorized as either (1) toxic-metabolic, (2) idiopathic, (3) genetic, (4) autoimmune, (5) recurrent and severe acute pancreatitis, or (6) obstructive (TIGAR-O system). After classification, staging of pancreatic function, injury, and fibrosis becomes the next major concern. Further research is needed to determine the clinical and natural history of chronic pancreatitis developing in the context of various risk factors. New methods are needed for early diagnosis of chronic pancreatitis, and new therapies are needed to determine whether interventions will delay or prevent the progression of the irreversible damage characterizing end-stage chronic pancreatitis.

Alcohol intake, cigarette smoking, and body mass index in patients with alcohol-associated pancreatitis

The differential diagnosis between acute and chronic alcohol-associated pancreatitis is often difficult or impossible at onset of the disease. A study was conducted to determine possible relationships between patients suffering from a first episode of acute alcoholic pancreatitis and patients with unequivocal chronic alcoholic pancreatitis, comparing age, drinking and smoking habits, and body mass index (BMI). Two groups of men were considered. The first group consisted of 67 patients with a diagnosis of acute alcohol-associated pancreatitis in the absence of other potential pathogenic factors; in this group, 48 of the 56 patients surviving the acute attack were submitted to imaging studies for a median period of 9 years. The second group consisted of 396 patients with chronic alcoholic pancreatitis with a median follow-up period of 12 years. The variables that differed significantly in the two groups were BMI (p < 0.009) and number of smokers (p < 0.001). Logistic regression analysis selected only BMI with an odds ratio of 1.19 (95% CI, 1.07-1.33; p < 0.00015) in favor of acute alcoholic pancreatitis. In male patients, from an epidemiologic standpoint, only smoking habits and BMI are significant differences at clinical onset between the two types of pancreatitis.

Genetic predispositions to acute and chronic pancreatitis

Advances in molecular genetics have provided the powerful tools necessary to identify the key molecules and mechanisms that underly the disease process. Continued work in this area promises to reveal new insights as new disease genes are discovered. This article focuses on the insights into the cause of acute and chronic pancreatitis gained by investigation of the HP genes, the diagnosis of the known mutations, the fascinating observation of nonpenetrance, and a look at future directions.

Long-term follow-up after the first episode of acute alcoholic pancreatitis: time course and risk factors for recurrence

BACKGROUND

Owing to the current lack of long-term follow-up data on the recurrence of alcohol-induced acute pancreatitis (AP), we studied the pattern of recurrence and determined the characteristics of the disease to predict the recurrence.

METHODS

Between 1972 and 1991, 2678 AP episodes were detected; 1555 were induced by alcohol, and 591 of them were the first episode. During the first alcohol-induced AP 29 patients died and were excluded from further analysis. Of the 562 included, 503 were men, and 59 women. Admission serum tests, severity index, development of complications, intensive care unit and hospital stay, and need for surgery were assessed. Case records were studied. The national database was used to detect admissions to other hospitals.

RESULTS

Overall, 260 (46%) developed recurrent disease. Of the first relapses, 80% developed during 4 years. The recurrence rate has not changed with time. Age less than 45 years increased the risk (odds ratio (OR) = 2.42; 95% confidence interval (CI), 1.30-4.50). The risk factors of the first alcohol-induced AP associated with the development of multi-recurring pancreatitis are age <45 years (OR, 2.42; 95% CI, 1.59-13.0), 0-2 positive Glasgow criteria (OR, 2.45; 95% CI, 1.16-5.19), and arterial oxygen tension >60 mmHg (OR, 9.90; 95% CI, 1.32-74.3).

CONCLUSIONS

Fewer than half of the patients develop recurrent alcohol-induced AP. Younger patients are at the highest risk of recurrence. Those whose first alcohol-induced pancreatitis episode was not severe are at a higher risk of developing multi-recurring pancreatitis.

Progression from acute to chronic pancreatitis: a physician's view

Whether or not AP may progress to the chronic form is controversial. Equally debatable is whether AP caused by alcohol abuse develops in a chronically diseased gland or in a normal pancreas. As for the state of the gland, several postmortem studies have shown that AP may occur after acute alcohol abuse in the normal pancreas. As for progression from acute to chronic pancreatitis, many experimental studies have demonstrated signs of the chronic from of the disease in animals, but these signs were reversible. Some clinical studies have shown that alcohol-induced pancreatitis may progress to chronic pancreatitis. There are, however, presently no predictive parameters indicating when such a progression does or does not occur.

New insights into hereditary pancreatitis

The recent discovery that mutations in the trypsinogen gene are responsible for acute and chronic pancreatitis, and that patients with hereditary pancreatitis are at great risk for pancreatic cancer, has opened the door to understanding many aspects of pancreatic disease. This review focuses on the clinical presentation of hereditary pancreatitis, the mechanism of disease, and implications of this disease on understanding acute and chronic pancreatitis.

Scanning electron microscope examination of pancreatic ducts in stroke-prone spontaneously hypertensive rats (SHRSP)

CONCLUSION

Ischemic injury to the pancreatic ductal cells causes stasis of pancreatic juice, which in turn induces chronic pancreatitis.

BACKGROUND

The pathogenesis of chronic ischemic pancreatitis is still unclear.

METHODS

In 12-, 24-, and 36-wk-old male stroke-prone spontaneously hypertensive rats (SHRSP), which have sclerotic arterioles with a marked narrowing lumen in the pancreas, pancreatic tissue was examined using light and scanning electron microscopy. Corrosion casts of pancreatic ducts and blood vessels were examined using scanning electron microscopy.

RESULTS

Ductular proliferation, tortuous ductal channels, crater-like depressions of ductal inner surfaces, and long cilia of ductal cells were found to be sporadically distributed throughout the pancreatic tissue. Similar pancreatic abnormalities had been found in previous studies using WBN/Kob rats that exhibited pancreatic juice stasis. A few interlobular ducts in the pancreatic tissue of the SHRSP had an inner surface that was gyrus-like in appearance, a feature not found in WBN/Kob rats.

Redifferentiation and apoptosis of pancreatic cells during acute pancreatitis

The pancreatic cells reorganize their genetic program in a rapid and precise manner during the course of pancreatitis. These phenotypic changes probably confer increased resistance to acute pancreatitis. Then, understanding the mechanism and the finality of these changes can allow us to act earlier and more efficiently against acute pancreatitis with the development of rational therapeutic strategies. Two major phenotypic changes that occur during acute pancreatitis are the appearance of stem cells and activation of the apoptotic program of the acinar cells. In this article I discuss a recent observation about origin and pluripotency of the tubular complex-forming cells during the postacute period of pancreatitis. In addition, I summarize our knowledge on apoptosis in the pancreatic cells, particularly during acute pancreatitis.

Progression of alcoholic acute to chronic pancreatitis

Alcoholic chronic pancreatitis usually progresses from acute attacks to chronic pancreatitis within one to 19 years. The factors responsible for the appreciable variability in progression are unclear. In this study the relation between progression and the incidence and severity of acute episodes in a large cohort of patients with alcoholic chronic pancreatitis was analysed. All patients with at least one documented episode of acute pancreatitis have been studied prospectively over the past 30 years according to our protocol. Patients were classified according to their long term course into (a) calcific (n = 185), (b) non-calcific (n = 30), and (c) non-progressive (n = 39) chronic pancreatitis groups. The yearly incidence of acute attacks of pancreatitis was significantly higher in groups (a) and (b) than in group (c). Furthermore, the progression rate to advanced chronic pancreatitis (groups (a) and (b)) correlated with the incidence of severe pancreatitis (associated with pseudocysts in more than 55%). Pseudocysts were located primarily in the cephalic pancreas in groups (a) and (b) (58-71%) and in the pancreatic tail in group (c) (61%). In conclusion, these data suggest that the progression of acute to chronic pancreatitis is closely related to the incidence and severity of acute attacks. This finding and the primary location of pseudocysts in the cephalic pancreas (groups (a) plus (b)) are compatible with the 'necrosis-fibrosis' pathogenetic hypothesis.