Can We Detect Chronic Pancreatitis With Low Serum Pancreatic Enzyme Levels?

Amylase and lipase levels in the metabolic syndrome and type 2 diabetes: A longitudinal study in rhesus monkeys

Latent associations between low serum amylase and reduced plasma insulin levels and increased adiposity have been described previously in a small study of asymptomatic middle-aged humans. In the present study, we sought to determine the nature of such changes during the longitudinal progression from metabolically normal to overt type 2 diabetes mellitus (T2DM) in nonhuman primates (NHPs), a disease that appears to be the same in both pathophysiology and underlying mechanisms as that which most commonly develops in middle-aged adult humans. Amylase and lipase levels were characterized in 157 unrelated adult rhesus monkeys (Macaca mulatta); 38% developed T2DM while under study. In all monkeys, multivariable linear regression analysis revealed that amylase could be negatively predicted by % body fat (β -0.29; p = 0.002), age (β -0.27; p = 0.005), and HbA1c (β -0.18; p = 0.037). Amylase levels were positively predicted by lipase levels (β = 0.19; p = -0.024) in all NHPs included in the study. Amylase was significantly lower in NHPs with metabolic syndrome (p < 0.001), prediabetes (PreDM) (p < 0.001), and T2DM (p < 0.001) compared to metabolically normal adult NHPs. Lipase increased in NHPs with PreDM (p = 0.005) and T2DM (p = 0.04) compared to normal NHPs. This is the first longitudinal study of any species, including humans, to show the dynamics of amylase and lipase during the metabolic progression from normal to metabolic syndrome, to PreDM and then to overt T2DM. The extraordinary similarity between humans and monkeys in T2DM, in pancreatic pathophysiology and in metabolic functions give these findings high translational value.

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.

Analytical validation of an ELISA for the measurement of feline pancreas-specific lipase and re-evaluation of the reference interval and decision threshold for diagnosing pancreatitis

BACKGROUND

The diagnosis of feline pancreatitis can be challenging. The clinical presentation often includes mild, nonspecific clinical signs, such as vomiting, anorexia, and weight loss. Measurement of feline pancreatic lipase immunoreactivity (fPLI) concentration in serum has been reported to be sensitive and specific for a diagnosis of pancreatitis in cats. However, analytical validation for a widely available commercial assay for the measurement of fPLI concentration has not been published.

OBJECTIVE

We aimed to analytically validate the Spec fPL assay (IDEXX Laboratories, Westbrook, ME), a commercial ELISA for the measurement of fPLI concentration, and re-evaluate its reference interval and decision threshold for diagnosing pancreatitis in cats.

METHODS

Dilutional linearity, accuracy, precision, and the effect of interfering substances were assessed. The upper limit of the reference interval was calculated based on the 95th percentile of results from clinically healthy cats (n = 107), and a decision threshold for diagnosing pancreatitis was calculated with an expected specificity of 99%.

RESULTS

Analytical validation demonstrated good linearity, accuracy, and precision, as well as the absence of interference from lipemia, hemolysis, or icterus. The upper limit of the reference interval for Spec fPL was determined to be 4.4 μg/L, and the decision threshold (a theoretical cut-off) for diagnosing pancreatitis was determined to be 8.8 μg/L based on a desired specificity of 99%.

CONCLUSIONS

The Spec fPL assay is analytically valid, and results suggest that a decision threshold of 8.8 μg/L would have high diagnostic specificity for excluding clinically healthy cats.

Evaluation of circulating miR-216a and miR-217 as biomarkers of pancreatic damage in the L-arginine-induced acute pancreatitis mouse model

We investigated the usefulness of circulating miR-216a-5p and miR-217-5p that are pancreas-enriched micro RNAs (miRNAs) as biomarkers of acute pancreatic damage, and compared them with conventional pancreatic biomarkers in L-arginine-induced acute pancreatitis mouse model. As the results, amylase and lipase levels apparently increased and peaked on Day 3 when acute pancreatitis including acinar cell degeneration/necrosis and inflammatory cell infiltration reached its peak. In contrast, miR-216a-5p and miR-217-5p increased from Day 1 when histopathological findings in the acinar cells were limited to decreased zymogen granules, and the increases in ratios were much higher than those of amylase and lipase. The miRNAs remained at high levels until Day 5 when the pseudo-tubular complex and replacement of inflammatory cells and fibrotic cells were apparent instead of necrosis, whereas amylase and lipase levels decreased to the control levels. Furthermore, we examined the relationship between biomarker levels and histopathological degeneration/necrosis scores in the acinar cells. miR-216a-5p and miR-217-5p levels increased depending on the score of degeneration/necrosis, and all individual miRNAs exceeded the control levels from a score of 2 (focal necrosis), whereas all individual amylase and lipase levels exceeded the control levels at scores of 4 (lobular necrosis) and 3 (sublobular necrosis), respectively. In conclusion, we demonstrated that circulating miR-216a-5p and miR-217-5p could detect pancreatic damage earlier with greater magnitude, and the sensitivity to detect acinar cell degeneration/necrosis was superior to that of conventional biomarkers in the L-arginine-induced acute pancreatitis mouse model.

Associations Between Iron Homeostasis and Pancreatic Enzymes After an Attack of Pancreatitis

OBJECTIVES

Dysregulation of iron homeostasis and exocrine pancreatic dysfunction are linked but remain undefined in individuals with a history of pancreatitis. The objective is to investigate the relationship between iron homeostasis and pancreatic enzymes in individuals after a pancreatitis attack.

METHODS

This was a cross-sectional study of adults with a history of pancreatitis. Markers of iron metabolism (hepcidin and ferritin) and pancreatic enzymes (pancreatic amylase, pancreatic lipase, and chymotrypsin) were measured in venous blood. Habitual dietary iron intake data (total, heme, and nonheme iron) were collected. Multivariable linear regression analyses were performed while considering covariates.

RESULTS

One hundred and one participants were studied at a median of 18 months after their last pancreatitis attack. Hepcidin was significantly associated with pancreatic amylase (β coefficient, -6.68; 95% confidence interval, -12.88 to -0.48; P = 0.035) and heme iron intake (β coefficient, 0.34; 95% confidence interval, 0.08 to 0.60; P = 0.012) in the adjusted model. Hepcidin was not significantly associated with pancreatic lipase or chymotrypsin. Ferritin was not significantly associated with pancreatic enzymes and dietary iron intake.

CONCLUSIONS

An iron homeostasis-exocrine pancreas crosstalk exists in individuals after an attack of pancreatitis. The role of iron homeostasis in pancreatitis warrants high-quality purposely-designed studies.

Effect of calcineurin inhibitor on post-endoscopic retrograde cholangiopancreatography pancreatitis in patients with liver transplantation: a propensity-matched cohort study

BACKGROUND/AIMS

A calcineurin inhibitor may alter pancreatic function and inflammatory reaction. This study aimed to determine the possible pharmacologic effect of the calcineurin inhibitor, tacrolimus, on pancreatic function, and to determine its preventive effect on post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis in liver transplantation (LT) patients.

METHODS

The serum amylase and lipase values before and after LT were compared. The frequency of post-ERCP pancreatitis was compared between non-LT and LT patients, using propensity score matching method.

RESULTS

Median serum amylase values (normal range, 19 to 86 U/L) were 49.0 U/L (38.0 to 68.0) before LT and 27.0 U/L (19.3 to 36.8) after LT, and median serum lipase values (normal range, 7 to 59 U/L) were 40.0 U/L (26.5 to 54.0) before LT and 10.5 U/L (6.0 to 21.0) after LT. Both serum amylase and lipase values significantly decreased after LT (p < 0.001), and to a level comparable to chronic pancreatitis. There was a marginal significant difference between the non-LT and LT groups before the propensity score matching with respect to frequency of post-ERCP pancreatitis (16 [3.2%] in non-LT group vs. 2 [0.9%] in LT group, p = 0.069). After propensity score matching, a marginal significant difference still existed with respect to frequency of post-ERCP pancreatitis (7 [4.8%] in non-LT group vs. 1 [0.7%] in LT group, p = 0.067).

CONCLUSION

The immunosuppression with calcineurin inhibitor may reduce not only the pancreatic enzyme dynamics but also inciting inflammatory event including post-ERCP pancreatitis.

Pancreatic Fibrosis and Chronic Pancreatitis: Mini-Review of Non-Histologic Diagnosis for Clinical Applications

Pancreatic fibrosis is the dominant reversible pathological change and diagnostic factor in early chronic pancreatitis, defined by a mechanistic approach proposed in 2016. Main guidelines for chronic pancreatitis were published by the American Pancreas Association in 2014, the Japanese Society of Gastroenterology in 2015, and United European Gastroenterology in 2017. All three sets of guidelines mentioned that the staging of chronic pancreatitis is important but challenging. There are various image modalities for the non-histologic diagnosis of pancreatic fibrosis: (1) shear wave elastography, such as an acoustic radiation force impulse with a cut-off value of 1.4 m/s; (2) strain elastography using grades of strain; (3) endoscopic ultrasonography using the Rosemont criteria or endoscopic ultrasound criteria for early chronic pancreatitis proposed by the Japan Pancreas Society; (4) computed tomography using the Hounsfield scale or number of micro-calcifications; and (5) magnetic resonance imaging using the apparent diffusion coefficient and the T1w flash and T2w HASTE sequences. The clinical applications are to (1) evaluate pancreatic tumors and inflammatory disease; (2) monitor dyspepsia with early chronic pancreatitis; (3) monitor individuals with a high risk of pancreatic cancer; (4) analyze a fatty pancreas with fibrosis; (5) predict a fistula after pancreatic surgery; and (6) predict outcomes for chronic pancreatitis or pancreatic cancer. The selection of tools will be dependent on the clinical scenario. Conclusion: There are various modalities for the non-histologic diagnosis of pancreatic fibrosis. The selection of the optimal device will be dependent on the clinical scenario.

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

Background

Pancreatic function testing and imaging are used to inform the diagnosis of chronic pancreatitis, but most of these methods are time- and cost-consuming or lack diagnostic accuracy.

Objective

We investigated the utility of pancreas-specific plasma amylase for assessment and diagnosis of chronic pancreatitis.

Design

This was a prospective study of 121 consecutive patients with chronic pancreatitis and a reference population of 94 healthy controls. Pancreas-specific plasma amylase level was determined and analysed for its association with exocrine pancreatic insufficiency, diabetes and other clinical variables. Receiver operating characteristic curve analyses were performed to determine the diagnostic utility of plasma amylase for diagnosing chronic pancreatitis and to study associations with disease severity. The findings were validated in a further cohort of 57 patients with chronic pancreatitis.

Results

Significant and independent associations between plasma amylase level and duration of chronic pancreatitis as well as the presence of exocrine pancreatic insufficiency and diabetes were observed (all p < 0.001). An amylase level below 17.3 U/l had a high specificity (94%) and moderate sensitivity (59%) for the diagnosis of chronic pancreatitis. Diagnostic performance was influenced by disease stage with the best performance observed for advanced disease. The findings were replicated in the validation cohort.

Conclusion

Pancreas-specific plasma amylase may provide a clinically useful mean for assessment and diagnosis of chronic pancreatitis.

Recent advances in the diagnosis and management of chronic pancreatitis

Chronic pancreatitis is a chronic condition characterized by pancreatic inflammation that causes fibrosis and the destruction of exocrine and endocrine tissues. Chronic pancreatitis is a progressive disease, and no physiological treatment is available to reverse its course. However, with advances in medical technology, the existing diagnostic and treatment methods for chronic pancreatitis are evolving. Managing patients with chronic pancreatitis is challenging and necessitates a multidisciplinary approach. In this review, we discuss the recent advances in the diagnosis and management of chronic pancreatitis and introduce future alternative modalities.

Low Serum Pancreatic Amylase and Lipase Values Are Simple and Useful Predictors to Diagnose Chronic Pancreatitis

Background/Aims

This study aimed to evaluate the diagnostic role of low serum amylase and lipase values in the detection of chronic pancreatitis.

Methods

Patients underwent endoscopic retrograde cholangiopancreatography and were diagnosed with non-calcific chronic pancreatitis (NCCP; n=99) and calcific chronic pancreatitis (CCP; n=112). Patient serum amylase and lipase values were compared with those of healthy controls (H; n=170).

Results

The median serum amylase (normal range, 19 to 86 U/L) and lipase values (7 to 59 U/L) (P₂₅-P₇₅) were 47.0 (39.8 to 55.3) and 25.0 (18.0 to 35.0) for H, 34.0 (24.5 to 49.0) and 19.0 (9.0 to 30.0) for NCCP, and 30.0 (20.0 to 40.8) and 10.0 (3.0 to 19.0) for CCP, respectively. The cutoff values with the highest diagnostic accuracy for discriminating NCCP from H were 40 U/L for amylase and 20 U/L for lipase, respectively, and for CCP from H were 38 U/L for amylase and 15 U/L for lipase, respectively. For the diagnosis of NCCP with a criterion of serum amylase <40 and lipase <20 U/L, the sensitivity, specificity, positive predictive value, and negative predictive values were 37.4%, 88.8%, 66.1%, and 70.9%, respectively.

Conclusions

Serum amylase and/or lipase levels below the normal serum range are highly specific for chronic pancreatitis patients. Clinicians should not ignore low serum pancreatic enzyme values.