Increased serum pancreatic enzymes in uremia: relation with treatment modality and pancreatic involvement

Non-pancreatic hyperlipasemia: A puzzling clinical entity

BACKGROUND

Increased lipase level is a serological hallmark of the diagnosis of acute pancreatitis (AP) but can be detected in various other diseases associated with lipase leakage due to inflammation of organs surrounding the pancreas or reduced renal clearance and/or hepatic metabolism. This non-pancreatic hyperlipasemia (NPHL) is puzzling for attending physicians during the diagnostic procedure for AP. It would be clinically beneficial to identify the clinical and laboratory variables that hinder the accuracy of lipase diagnosis with the aim of improve it. A more precise description of the NPHL condition could potentially provide prognostic factors for adverse outcomes which is currently lacking.

AIM

To perform a detailed clinical and laboratory characterization of NPHL in a large prospective patient cohort with an assessment of parameters determining disease outcomes.

METHODS

A Hungarian patient cohort with serum lipase levels at least three times higher than the upper limit of normal (ULN) was prospectively evaluated over 31 months. Patients were identified using daily electronic laboratory reports developed to support an ongoing observational, multicenter, prospective cohort study called the EASY trial (ISRCTN10525246) to establish a simple, easy, and accurate clinical scoring system for early prognostication of AP. Diagnosis of NPHL was established based on ≥ 3 × ULN serum lipase level in the absence of abdominal pain or abdominal imaging results characteristic of pancreatitis.

RESULTS

A total of 808 patients [male, n = 420 (52%); median age (IQR): 65 (51-75) years] were diagnosed with ≥ 3 × ULN serum lipase levels. A total of 392 patients had AP, whereas 401 had NPHL with more than 20 different etiologies. Sepsis and acute kidney injury (AKI) were the most prevalent etiologies of NPHL (27.7% and 33.2%, respectively). The best discriminative cut-off value for lipase was ≥ 666 U/L (sensitivity, 71.4%; specificity, 88.8%). The presence of AKI or sepsis negatively affected the diagnostic performance of lipase. NPHL was associated with a higher in-hospital mortality than AP (22.4% vs 5.1%, P < 0.001). In multivariate binary logistic regression, not lipase but increased amylase level (> 244 U/L) and neutrophil-to-lymphocyte ratio (NLR) (> 10.37, OR: 3.71, 95%CI: 2.006-6.863, P < 0.001), decreased albumin level, age, and presence of sepsis were independent risk factors for in-hospital mortality in NPHL.

CONCLUSION

NPHL is a common cause of lipase elevation and is associated with high mortality rates. Increased NLR value was associated with the highest mortality risk. The presence of sepsis/AKI significantly deteriorates the serological differentiation of AP from NPHL.

Hyperlipasemia Sans Pancreatitis: A Case Series

Acute pancreatitis results in inflammation and autodigestion of pancreatic acinar cells leading to the elevation of pancreatic enzymes, namely, amylase and lipase. Serum lipase levels have long been considered a hallmark of acute pancreatitis. However, pancreatitis is not always the cause of elevated serum lipase levels. This series presents four patients who had elevated serum lipase levels without any demonstrable damage to the pancreas on imaging. On further evaluation, one of the patients was found to have acute on chronic kidney disease (CKD) whose lipase levels settled later. A patient presenting with an episode of acute gastroenteritis, later diagnosed to have Crohn's disease, also had hyperlipasemia, which improved after a course of initial antibiotics. Non-gastrointestinal causes, such as lupus nephritis and organophosphate (OP) poisoning, also had elevated lipase levels on presentation, in which the hyperlipasemia settled with supportive treatments. It is important to remember other causes of elevated lipase levels in patients with a normal pancreas on imaging studies.

Toxic-metabolic Risk Factors in Pediatric Pancreatitis: Recommendations for Diagnosis, Management, and Future Research

Pancreatitis in children can result from metabolic and toxic risk factors, but the evidence linking these factors is sparse. We review the evidence for association or causality of these risk factors in pancreatitis, discuss management strategies, and their rationale. We conducted a review of the pediatric pancreatitis literature with respect to the following risk factors: hyperlipidemia, hypercalcemia, chronic renal failure, smoking exposure, alcohol, and medications. Areas of additional research were identified. Hypertriglyceridemia of 1000 mg/dL or greater poses an absolute risk for pancreatitis; persistent elevations of calcium are predisposing. Further research is necessary to determine whether end-stage renal disease leads to increased pancreatitis in children similar to adults. It is unknown whether cigarette smoking exposure, which clearly increases risk in adults, also increases risk in children. The role of alcohol in pediatric pancreatitis, whether direct or modifying, needs to be elucidated. The evidence supporting most cases of medication-induced pancreatitis is poor. Drug structure, improper handling of drug by host, and bystander status may be implicated. Other pancreatitis risk factors must be sought in all cases. The quality of evidence supporting causative role of various toxic and metabolic factors in pediatric pancreatitis is variable. Careful phenotyping is essential, including search for other etiologic risk factors. Directed therapy includes correction/removal of any agent identified, and general supportive measures. Further research is necessary to improve our understanding of these pancreatitis risk factors in children.

PANCREATITIS OR NOT?--Elevated lipase and amylase in ICU patients

Elevation in serum levels of pancreatic enzymes (Hyperamylasemia and/or Hyperlipasemia) can occur in any Intensive Care Unit (ICU) patient either as a result of true acute pancreatitis (AP) or as a reflection of a non-pancreatic disease. Although most patients may not have clinical pancreatitis, identifying true acute pancreatitis in the ICU setting may be critical in the presence of associated co-morbid conditions of the disease for which the patient is being managed. With neither amylase nor lipase being specific for pancreatitis, it is important for the clinician to be aware of different causes of hyperamylasemia and hyperlipasemia, especially when clinical diagnosis of pancreatitis is unclear. This review will focus on understanding different non-pancreatic conditions where there is elevation of pancreatitis enzymes and to identify true acute pancreatitis in critically ill patients without typical symptoms.

Significant elevations of serum lipase not caused by pancreatitis: a systematic review

BACKGROUND

Many authors advocate lipase as the preferred serological test for the diagnosis of pancreatitis and a cut-off level of three or more times the upper limit of normal (ULN) is often quoted. The literature contains no systematic review that explores alternative causes of a lipase level over three times as high as the ULN. Such a review was therefore the objective of this study.

METHODS

The EMBASE and MEDLINE databases (1985 to August 2013) were searched for all eligible articles. Predetermined data were extracted and independently analysed by two reviewers.

RESULTS

In total, data from 58 studies were included in the final analysis. The following causes other than pancreatitis of lipase levels exceeding three times the ULN were found: reduced clearance of lipase caused by renal impairment or macrolipase formation; other hepatobiliary, gastroduodenal, intestinal and neoplastic causes; critical illness, including neurosurgical pathology; alternative pancreatic diagnoses, such as non-pathological pancreatic hyperenzymaemia, and miscellaneous causes such as diabetes, drugs and infections.

CONCLUSIONS

A series of differential diagnoses for significant serum lipase elevations (i.e. exceeding three times the ULN) has been provided by this study. Clinicians should utilize this knowledge in the interpretation and management of patients who have lipase levels over three times as high as the ULN, remaining vigilant for an alternative diagnosis to pancreatitis. The medical officer should be aware of the possibility of incorrect diagnosis in the asymptomatic patient.

The effect of renal replacement therapies on serum gastrointestinal system hormones

BACKGROUND

The kidney is a major site for the inactivation, degradation, and clearance of a variety of peptide hormones. It has been shown that the uremia increases or decreases gastrointestinal system (GIS) hormones. Moreover, studies investigating the serum GIS hormones levels in chronic renal failure (CRF) were conducted mainly in a particular period of the renal replacement therapy, and the changes caused by continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) could not be fully demonstrated. In this study, we investigated the effect of CAPD and HD on serum GIS hormones (amylase, lipase, trypsinogen, and gastrin) levels in CRF patients who were diagnosed for the first time.

METHODS

Serum amylase, lipase, trypsinogen, and gastrin levels were measured in 36 patients who were just diagnosed with CRF, 22 patients with CAPD and 14 patients with HD. GIS hormones of these patients were measured before treatment and three months from the beginning of CAPD and HD treatment. As the control group, 20 normal healthy cases with well-matched age and gender were used.

RESULTS

The mean serum amylase, lipase, secretin, and gastrin levels were found meaningfully decreased according to the beginning values at third months of the CAPD and HD treatment. However, they were higher than control group.

CONCLUSION

In patients receiving CAPD or HD as renal replacement therapy, GIS hormone levels were found to be lower, albeit higher than the healthy control group.

Evidence for impaired assimilation of protein in chronic renal failure

BACKGROUND

Protein malnutrition is a common finding in chronic renal failure (CRF) and is associated with poor outcome. We hypothesized that besides inadequate dietary protein intake and alterations in metabolism, deficient protein assimilation (digestion and absorption) might contribute to the pathogenesis of protein malnutrition in uremia.

METHODS

Protein assimilation was evaluated in 64 healthy volunteers and 119 CRF patients by means of a 13C protein breath test and/or quantification of p-cresol in a 24-hour urine collection. Both approaches provide reliable information on the efficiency of protein assimilation. Breath test results were expressed as maximum percentage of administered dose of 13C (%max) and cumulative percentage at the end of the test (%cum(end)). Data were stratified according to renal function.

RESULTS

As compared to subjects with glomerular filtration rate (GFR) > or = 60 mL/min/1.73 m2, subjects with GFR < 30 mL/min/1.73 m2 demonstrated significantly lower breath test-derived parameters of protein assimilation (%max 3.97 +/- 0.23 vs. 5.20 +/- 0.23, P=0.0017; %cum(end) 13.91 +/- 0.86 vs. 17.40 +/- 0.80, P= 0.013) and significantly higher urinary output of p-cresol (54.88 mg/24 hours vs. 28.65 mg/24 hours, P= 0.0005). %max (r=0.399, P < 0.0001), %cum(end) (r=0.347, P=0.0007), and urinary p-cresol (r=-0.229, P=0.007) correlated significantly with GFR. Serum albumin correlated significantly with %max (r=0.399, P=0.0002), %cum(end) (r=0.408, P=0.0001), and urinary p-cresol output (r=-0.186, P=0.035).

CONCLUSION

Our data provide evidence that protein assimilation is impaired in CRF. This impairment might contribute to protein malnutrition in CRF.

Secondary hyperparathyroidism and brown tumor in dialyzed patients

Secondary hyperparathyroidism is one of the most common complications of chronic renal failure (CRF). Its pathogenesis is multifactorial and still not completely understood. Pathological mechanism of hypocalcemia, hyperphosphatemia and calcitriol deficiency are basic characteristics of CRF and main reason for morphological changes in parathyroid glands and hyperparathyroidism (HP). We present a case of a female patient born in 1975. At the age of 10, a urinary infection was diagnosed for the first time and treated. Six years later, as nausea and vomiting started, CRF based on bilateral reflux was diagnosed and the patient was included in the hemodialysis treatment. The patient was again examined in 1997, when biochemical parameters, including the level of parathyroid hormone, ultrasonography of the neck, scintigraphy of the skeleton and densitometry revealed secondary HP. Parathyreoidectomy was perfomed in 1998. During the follow up period, a tumefaction on a ramus mandibulae dex. was noticed, which was cytologically diagnosed as osteitis fibrosa, "brown tumor", a rare complication of the secondary HP. Surgery was performed and PHD was granuloma gigantocelulare. Prevention and therapy of secondary HP is a problem that demands early actions to avoid possible complications.