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Three Part Question

In [patients with abdominal pain] is [a single serum lipase better than a serum amylase] as [a diagnostic marker of pancreatitis]?

Clinical Scenario

A 45 year old female attends the emergency department with a four hour history of acute onset of epigastric pain. She has a history of alcohol usage. On examination you can elicit tenderness in the epigastrium but no peritonism. You are concerned that the patient may have pancreatitis. You wonder whether a serum lipase might be better than serum amylase as a diagnostic marker for pancreatitis in this patient.

Search Strategy

Medline and EMBASE 1966-06/02 using the OVID interface.
[{exp Abdominal pain OR abdominal pain.mp} OR {exp Pancreatitis OR exp Pancreatitis, Acute Necrotizing OR exp pancreatitis, alcoholic OR pancreatitis.mp} AND {exp Amylases OR amylase.mp} AND {exp Lipase OR lipase.mp} AND exp Diagnosis OR diagnosis.mp] LIMIT to human AND English.

Search Outcome

320 papers were found in total of which 313 were irrelevant or of insufficient quality for inclusion. The remaining 7 papers are shown in the table.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Steinberg WM et al, 1985, USA	166 patients with abdominal pain. 39 cases with confirmed pancreatitis v 127 Emergency dept attenders with abdominal pain. Gold standard - CT findings, ultrasound or laparotomy	Diagnostic study	Lipase upper limit	Spec 99%. Sens 86%.	Different gold standards Selected patient groups
			Amylase upper limit	Spec 89%. Sens 95%.
			Lipase best cut off	Spec 99%. Sens 87%.
			Amylase best cut off	Spec 99%. Sens 95%.
Kazmierczak S et al, 1991, USA	151 consecutive patients on whom serum amylase or lipase had been ordered	Diagnostic study	Diagnosis of pancreatitis	Similar ROC curves for amylase and lipase.	No gold standard Not all patients had test
Gumaste VV et al, 1993, USA	170 patients with abdominal pain	Diagnostic study	Lipase	Spec 99%. Sens 100%.	No gold standard Unblinded
			Amylase	Spec 99%. Sens 72%.
Clave P et al, 1995, Spain	384 patients admitted with abdominal pain	Diagnostic study	Diagnosis of pancreatitis	Area under ROC curve similar for serum amylase and lipase.	No gold standard Admitted patients
Chase CW et al, 1996, USA	306 patients admitted with abdominal pain.	Diagnostic study	Lipase	Diagnostic efficiency 94%	No gold standard
			Amylase	Diagnostic efficiency 91%
Kemppainen EA et al, 1997, Finland	500 consecutive patients with abdominal pain attending Emergency Departments in 2 centres	Diagnostic study	Lipase	Sens 94%, Spec 95%
			Amylase	Sens 85%, Spec 91%
Keim V et al, 1998, Germany	253 patients with acute abdominal painGold standard was CT scan/US scan of abdomen abdominal pain	Diagnostic study	Diagnosis of pancreatitis	Amylase sensitivity of 95% at 0-1 days, lipase 100%. ROC curve slightly superior for lipase.

Comment(s)

Concern has been expressed about the use of serum amylase to diagnose pancreatitis. Hyperamylasaemia has been reported in numerous abdominal conditions that can be confused with pancreatitis. Acute pancreatitis has also been reported in patients with a normal amylase. The studies mentioned suggest that serum amylase and lipase both have high levels of sensitivity and specifictiy for pancreatitis, although few studies looked directly at patients attending the emergency department with abdominal pain. On the whole comparative studies show serum lipase to be slightly superior to amylase as a diagnostic marker when used to rule in or out pancreatitis. Further work is needed to look at diagnostic assays in patients attending the emergency department with abdominal pain.

Clinical Bottom Line

Serum amylase and lipase are high sensitivity and specific diagnostic markers of acute pancreatitis. Some studies suggest serum lipase is better.

References

1. Steinberg WM, Goldstein SS, Davis ND et al. Diagnostic assays in Acute Pancreatitis. Ann Intern Med 1985;102:576-580.
2. Kazmierczak SC, Van Lente F, Hodges ED. Diagnostic and prognostic utility of phospholipase A activity in patients with acute pancreatitis: comparison with amylase and lipase. Clin Chem 1991;37(3):356-60.
3. Gumaste VV, Roditis N, Mehta D et al. Serum lipase levels in nonpancreatic abdominal pain versus acute pancreatitis. Am J Gastroenterol 1993;88(12)2051-5.
4. Clave P, Guillaumes S, Blanco I et al. Amylase, lipase, pancreatic isoamylase, and phospholipase A in diagnosis of acute pancreatitis. Clin Chem 1995;41(8):1129-34.
5. Chase CW, Barker DE, Russell WL et al. Serum amylase and lipase in the evaluation of acute abdominal pain. Am Surg 1996;62(12):1028-33.
6. Kemppainen EA, Hedstrom JI, Puolakkainen PA et al. Rapid measurement of urinary trypsinogen-2 as a screening test for acute pancreatitis. NEJM 1997;336(25):1788-93.
7. Keim V, Teich N, Fielder F et al. A comparison of lipase and amylase in the diagnosis of acute pancreatitis in patients with abdominal pain. Pancreas 1998;16(1):45-9.