Pancreas-specific plasma amylase for assessment and diagnosis of chronic pancreatitis: New insights on an old topic

What is the clinical significance of low serum amylase? Systematic review of the conditions associated with low serum amylase

Objective

Most studies have assessed the impact of elevated serum amylase levels in clinical practice, but only a few have investigated the significance of low serum amylase. We therefore, aimed to review the literature to understand the conditions associated with low serum amylase and its clinical relevance.

Method

This systematic review was performed in accordance with the criteria established in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search was conducted on Medline and Embase databases until November 2022. After identifying relevant titles, abstracts were read and data of eligible articles retrieved. The conditions associated with low serum amylase were evaluated. The quality of the studies was assessed using the Newcastle-Ottawa Score.

Results

Our search strategy identified 19 studies including a total of 15 097 patients for systematic review. All the studies were observational including two studies which used secretin-induced test. The main conditions associated with low serum amylase were diabetes mellitus (n=9), metabolic syndrome (n=3), chronic pancreatitis (CP) (n=3), non-alcoholic fatty liver disease (n=2) and obesity (n=1). Low serum amylase showed a high specificity (94%) with low sensitivity (38.7%-59%) in diagnosing chronic pancreatitis.

Conclusion

This systematic review revealed a unique insight into the relevance of low serum amylase in clinical practice. Low serum amylase can be a useful adjunct test in the assessment of patients with CP, pancreatic exocrine insufficiency, diabetes mellitus and metabolic syndrome.

Krüppel-like Factor 5 Plays an Important Role in the Pathogenesis of Chronic Pancreatitis

Chronic pancreatitis results in the formation of pancreatic intraepithelial neoplasia (PanIN) and poses a risk of developing pancreatic cancer. Our previous study demonstrated that Krüppel-like factor 5 (KLF5) is necessary for forming acinar-to-ductal metaplasia (ADM) in acute pancreatitis. Here, we investigated the role of KLF5 in response to chronic injury in the pancreas. Human tissues originating from chronic pancreatitis patients showed increased levels of epithelial KLF5. An inducible genetic model combining the deletion of Klf5 and the activation of KrasG12D mutant expression in pancreatic acinar cells together with chemically induced chronic pancreatitis was used. The chronic injury resulted in increased levels of KLF5 in both control and KrasG12D mutant mice. Furthermore, it led to numerous ADM and PanIN lesions and extensive fibrosis in the KRAS mutant mice. In contrast, pancreata with Klf5 loss (with or without KrasG12D) failed to develop ADM, PanIN, or significant fibrosis. Furthermore, the deletion of Klf5 reduced the expression level of cytokines and fibrotic components such as Il1b, Il6, Tnf, Tgfb1, Timp1, and Mmp9. Notably, using ChIP-PCR, we showed that KLF5 binds directly to the promoters of Il1b, Il6, and Tgfb1 genes. In summary, the inactivation of Klf5 inhibits ADM and PanIN formation and the development of pancreatic fibrosis.

ORAL N-ACETYL CYSTEINE VERSUS RECTAL INDOMETHACIN FOR PREVENTION OF POST ERCP PANCREATITIS: A MULTICENTER MULTINATIONAL RANDOMIZED CONTROLLED TRIAL

BACKGROUND

This multicenter multinational RCT designed to compare the efficacy of suppository indomethacin and NAC for prevention of PEP.

METHODS

During a 6-month period, all of the ERCP cases in seven referral centers were randomly assigned to receive either 1200 mg oral NAC, indomethacin suppository 100 mg, 1200 mg oral NAC plus indomethacin suppository 100 mg or placebo 2 hours before ERCP. The primary outcomes were the rate and severity of any PEP.

RESULTS

A total of 432 patients included (41.4% male). They were originally citizens of 6 countries (60.87% Caucasian). They were randomly allocated to receive either NAC (group A, 84 cases), rectal indomethacin (group B, 138 cases), NAC + rectal indomethacin (group C, 115 cases) or placebo (group D, 95 cases). The rate of PEP in groups A, B and C in comparison with placebo were 10.7%, 17.4%, 7.8% vs 20% (P=0.08, 0.614 & 0.01 respectively). The NNT for NAC, indomethacin and NAC + indomethacin was 11, 38 and 8 respectively.

CONCLUSION

Oral NAC is more effective than rectal indomethacin when compared to placebo for prevention of PEP and the combination of NAC and Indomethacin had the lowest incidence of PEP and may have synergistic effect in preventing of PEP (IRCT20201222049798N1; 29/12/2020).

Clinical and translational markers of severity and prognosis in chronic pancreatitis

PURPOSE OF REVIEW

The incidence of chronic pancreatitis as a progressive inflammation and fibrosis syndrome is on the rise due to increasing awareness and improved imaging modalities. Numerous classification systems have been suggested in recent years to describe the disease, but only few of them have been used to classify the severity and prognostic significance of the disease. Biomarkers for severity and (early) chronic pancreatitis diagnosis are not yet ready for clinical application.

RECENT FINDINGS

In using the M-ANNHEIM and Chronic Pancreatitis Prognosis Score (COPPS) classification system, the severity assessment and short- and medium-term disease progression is available. A prospectively validated biomarker for early chronic pancreatitis diagnosis is not yet available, metabolome-based approaches seem to have the greatest potential for clinical translation.

SUMMARY

Currently, due to the lack of universal definition for the early disease stage of chronic pancreatitis, it is difficult to accurately classify these patient cohorts in existing scoring systems. In principle, setting up a suitable scoring system would allow surveillance and establish a therapy approaches flanked by corresponding biomarker panel development. Therapy management of chronic pancreatitis and monitoring by means of scoring systems (such as the COPPS) would make a decisive contribution to improving patient treatment.

Clinical and biochemical characteristics of postpancreatitis diabetes mellitus: A cross-sectional study from the Danish nationwide DD2 cohort

BACKGROUND

Postpancreatitis diabetes mellitus (PPDM) is a common metabolic sequalae of acute and chronic pancreatitis. We conducted a cross-sectional study to examine the proportion of PPDM among patients clinically diagnosed with type 2 diabetes (T2D) in Denmark and their clinical and biochemical characteristics.

METHODS

We identified all past diagnoses of pancreatitis among patients in the Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort through linkage with national health registries. Using International Classification of Diseases, Tenth Revision codes we categorized patients as PPDM and further divided them into acute/chronic subtypes (PPDM-A and PPDM-C). We assessed PPDM prevalence and examined associations with clinical and biochemical parameters using log binomial or Poisson regression to calculate age-/sex-adjusted prevalence ratios (aPRs).

RESULTS

Among 5564 patients with a clinical diagnosis of T2D, 78 (1.4%) had PPDM. Compared to T2D, PPDM patients were more often underweight or normal weight (body mass index ≤25.0 kg/m² : aPR 2.3; 95% confidence interval [CI]: 1.6-3.2) and had lower waist-to-hip ratio (≤0.95/≤0.80 in men/women: aPRs 1.8; 95% CI: 1.2-2.7). PPDM patients had lower plasma amylase levels (<17 U/L: aPRs 2.2; 95% CI: 1.1-4.3), higher insulin sensitivity (homeostatic model assessment 2S [HOMA2S] >63: aPR 2.0; 95% CI: 1.2-3.2) and tended to have worse glycaemic control (HbA1c ≥8.0%: aPRs 1.4; 95% CI: 0.8-2.4). PPDM-A was largely indistinguishable from T2D, whereas PPDM-C had impaired insulin secretion, higher insulin sensitivity, and worse glycemic control.

CONCLUSIONS

The proportion of PPDM among patients with clinically diagnosed T2D is ~1.5% in an everyday clinical care setting. Glucose metabolism of PPDM-A is largely indistinguishable from T2D, whereas PPDM-C differs in relation to insulin secretion and sensitivity.

Low and high pancreatic amylase is associated with pancreatic cancer and chronic pancreatitis

Incidences of pancreatic cancer and acute and chronic pancreatitis are rising globally, and often no curative treatment is available at the time of diagnosis. We tested the hypothesis that low and high plasma concentrations of pancreatic amylase are associated with increased risk of pancreatic cancer, acute pancreatitis, and chronic pancreatitis in the general population. We included 101,765 individuals (55% women) aged 20-100 years from the Copenhagen General Population Study with baseline measurements of plasma pancreatic amylase. After recruitment in 2004-2015 during a median 9 years of follow-up (range 0-15), we collected information about diagnoses of pancreatic cancer, acute pancreatitis, and chronic pancreatitis from the national Danish Patient Registry, the national Danish Cancer Registry, and the national Danish Causes of Death Registry. The median age was 58 years (interquartile range: 48-67) and the median plasma pancreatic amylase 32 U/L (26-40). During follow-up, 442 individuals were diagnosed with pancreatic cancer, 282 with chronic pancreatitis, and 401 with acute pancreatitis. Compared to individuals with pancreatic amylase levels in the 41st-60th percentiles, those with extreme low (1st-2.5th percentiles) and extreme high (97.5th-100th percentiles) pancreatic amylase had hazard ratios of 2.4 (95% confidence interval; 1.6-3.6) and 2.2 (1.4-3.7) for pancreatic cancer, of 1.8 (1.1-3.3) and 3.2 (1.8-5.6) for chronic pancreatitis, and of 1.1 (0.6-1.8) and 1.5 (0.8-2.7) for acute pancreatitis, respectively. In apparently healthy individuals from the general population, extreme low and extreme high plasma pancreatic amylase were associated with 2-threefold higher risk of both pancreatic cancer and chronic pancreatitis.

Current advances in the management of chronic pancreatitis

Chronic pancreatitis is characterized by irreversible destruction of pancreatic parenchyma and its ductal system resulting from longstanding inflammation, leading to fibrosis and scarring due to genetic, environmental, and other risk factors. The diagnosis of chronic pancreatitis is made based on a combination of clinical features and characteristic findings on computed tomography or magnetic resonance imaging. Abdominal pain is the most common symptom of chronic pancreatitis. The main aim of treatment is to relieve symptoms, prevent disease progression, and manage complications related to chronic pancreatitis. Patients who do not respond to medical treatment or not a candidate for surgical treatment are usually managed with endoscopic therapies. Endoscopic therapies help with symptoms such as abdominal pain and jaundice by decompression of pancreatic and biliary ducts. This review summarizes the risk factors, pathophysiology, diagnostic evaluation, endoscopic treatment of chronic pancreatitis, and complications. We have also reviewed recent advances in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided therapies for pancreatic duct obstruction due to stones, strictures, pancreatic divisum, and biliary strictures.

Pathological Mechanisms in Diabetes of the Exocrine Pancreas: What's Known and What's to Know

The clinical significance of diabetes arising in the setting of pancreatic disease (also known as diabetes of the exocrine pancreas, DEP) has drawn more attention in recent years. However, significant improvements still need to be made in the recognition, diagnosis and treatment of the disorder, and in the knowledge of the pathological mechanisms. The clinical course of DEP is different from type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). DEP develops in patients with previous existing exocrine pancreatic disorders which damage both exocrine and endocrine parts of pancreas, and lead to pancreas exocrine insufficiency (PEI) and malnutrition. Therefore, damage in various exocrine and endocrine cell types participating in glucose metabolism regulation likely contribute to the development of DEP. Due to the limited amount of clinical and experimental studies, the pathological mechanism of DEP is poorly defined. In fact, it still not entirely clear whether DEP represents a distinct pathologic entity or is a form of T2DM arising when β cell failure is accelerated by pancreatic disease. In this review, we include findings from related studies in T1DM and T2DM to highlight potential pathological mechanisms involved in initiation and progression of DEP, and to provide directions for future research studies.

Chronic pancreatitis

Chronic pancreatitis is a multifactorial, fibroinflammatory syndrome in which repetitive episodes of pancreatic inflammation lead to extensive fibrotic tissue replacement, resulting in chronic pain, exocrine and endocrine pancreatic insufficiency, reduced quality of life, and a shorter life expectancy. The incidence and prevalence of chronic pancreatitis is rising and no curative treatment is available. Using novel diagnostic algorithms, definitive chronic pancreatitis can be diagnosed by imaging criteria alone, whereas probable chronic pancreatitis requires clinical features and imaging criteria. Criteria for the diagnosis of early chronic pancreatitis are still under discussion and need prospective validation in clinical trials. Cross-sectional imaging should be used first; endoscopic ultrasound is needed only when CT or MRI are inconclusive or to plan therapeutic interventions. Management of chronic pancreatitis requires an interdisciplinary approach including primary care practitioners, gastroenterologists, surgeons, radiologists, pain specialists, and nutritional therapists. Patients with chronic pancreatitis should be seen at least once a year and re-evaluated for causal risk factors, symptom control, and complications such as malnutrition, pancreatic exocrine insufficiency, and diabetes; refer to a specialised centre if symptoms are poorly controlled or there is risk of deterioration. Scoring systems to monitor disease progression have been developed and validated internationally. Interventional treatments for pain or cholestasis should be done by specialists only, and early discussion of treatment approaches should include all medical disciplines involved in care. Throughout this Seminar, we address research needs such as staging of pancreatitis, aspects of malnutrition and pain, and cancer surveillance, to help improve the care of patients.