Is amylase elevated in patients with leptospirosis?

Amylase Elevation in Leptospirosis

Yes, amylase is frequently elevated in leptospirosis, with hyperamylasemia documented in up to 65% of patients with severe disease, though this elevation can originate from both pancreatic and non-pancreatic sources. 1

Frequency and Clinical Significance

• Hyperamylasemia occurs in the majority of severe leptospirosis cases, particularly those presenting with jaundice, with documented rates reaching 65% 1
• Serum amylase or lipase levels were elevated in all patients who developed acute pancreatitis as a complication of leptospirosis 2
• In a case series from Sri Lanka, 4 out of 6 severe leptospirosis patients had serum amylase levels exceeding 900 IU/L (range 941-2420) 3
• Hyperamylasemia was recorded in every patient in whom it was measured in a fatal leptospirosis case series, with values above 180 IU/L in 3 cases 4

Critical Distinction: Pancreatic vs Non-Pancreatic Sources

The elevation of amylase in leptospirosis can originate from both pancreatic and non-pancreatic sources, making interpretation challenging. 1

• While hyperamylasemia is common, actual acute pancreatitis is an uncommon complication of leptospirosis 1
• The cause of hyperamylasemia cannot be explained solely by renal insufficiency (which is common in leptospirosis), because amylase levels often exceed 3-4 times the normal value—the upper limit typically seen in renal failure alone 1
• Non-pancreatic sources of amylase elevation must be considered even when levels are significantly elevated 1

Clinical Presentation and Monitoring

Acute pancreatitis in leptospirosis can occur without typical abdominal or back pain, making enzyme monitoring essential. 2

• The time of onset for pancreatitis is inconsistent and unpredictable during the disease course 2
• Several documented cases showed pancreatitis without apparent abdominal or back pain 2
• In one case, serum amylase increased over time despite initial improvement with antimicrobial therapy, and pancreatitis was only detected on day 9 of hospitalization 2
• Common presenting symptoms include fever, chills, vomiting, myalgia, dehydration, abdominal pain, and diarrhea, though abdominal pain is not universally present 4

Recommended Approach

Regular monitoring of pancreatic enzymes (both amylase and lipase) is recommended when leptospirosis is suspected, even in the absence of abdominal symptoms. 2

• Measure both amylase and lipase, as lipase provides higher specificity for true pancreatic involvement 5
• Monitor serum glucose and electrolytes closely, as acute hyperglycemia and insulin requirement may indicate pancreatic involvement 6
• Consider imaging (CT scan) if enzyme levels are significantly elevated or rising, particularly if amylase exceeds 3 times the upper limit of normal 5
• All patients with severe leptospirosis who develop abdominal pain should raise suspicion for pancreatic involvement 4

Associated Laboratory Findings

• Thrombocytopenia is evident in the majority of cases 4
• Acute kidney injury occurs in essentially all severe cases 3
• Hepatitis with mild elevation of AST and ALT is common 4
• Low serum calcium may be present in cases with true pancreatitis 3
• Neutrophilic leukocytosis is typically detected in the initial stage 3

Common Pitfall

Do not assume that hyperamylasemia in leptospirosis always indicates acute pancreatitis—the elevation may be from non-pancreatic sources, and clinical correlation with imaging is essential to confirm true pancreatic involvement. 1 However, the high frequency of amylase elevation and the potential for silent pancreatitis mandate routine enzyme monitoring in all suspected or confirmed leptospirosis cases. 2