What is the workup for persistent leukocytosis and pancreatitis?

From the Guidelines

Persistent leukocytosis and pancreatitis require a thorough workup to determine the underlying cause and severity of the condition. The initial step in the workup is to establish the diagnosis of acute pancreatitis, which should be based on compatible clinical features and elevations in amylase or lipase levels, with lipase being more specific and preferred 1.

Diagnostic Criteria

• Elevations in amylase or lipase levels greater than 3 times the upper limit of normal, in the absence of renal failure, are most consistent with acute pancreatitis 1.
• The diagnosis of acute pancreatitis should be established within 48 hours of admission 1.

Etiology Determination

• The etiology of acute pancreatitis should be able to be established in at least three fourths of patients, with a focus on previous symptoms or documentation of gallstones, alcohol use, history of hypertriglyceridemia or hypercalcemia, family history of pancreatic disease, prescription and nonprescription drug history, history of trauma, and the presence of concomitant autoimmune diseases 1.
• At admission, all patients should have serum obtained for measurement of amylase or lipase level, triglyceride level, calcium level, and liver chemistries (bilirubin, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase) 1.
• Abdominal ultrasonography should be obtained at admission to look for cholelithiasis or choledocholithiasis, and repeat ultrasonography after recovery should be performed if the initial ultrasound examination is inadequate or if a suspicion of gallstone pancreatitis is still present 1.

Imaging

• Computed tomography (CT) of the abdomen using intravenous contrast enhancement can be used to confirm the diagnosis and assess the severity of acute pancreatitis, but an early CT (within 72 hours of illness onset) might underestimate the amount of pancreatic necrosis 1.
• Contrast-enhanced computed tomography (CE-CT) or magnetic resonance imaging (MRI) should be performed in all patients with severe acute pancreatitis, with optimal timing for the first CE-CT assessment being 72-96 hours after the onset of symptoms 1.

Laboratory Findings

• Serum pancreatic enzyme measurement is the “gold standard” for the diagnosis of acute pancreatitis, with lipase being more reliable than amylase 1.
• Other laboratory findings used to characterize an episode of severe acute pancreatitis include BUN > 20 mg/dl or rising BUN, hematocrit (HCT) > 44% or rising HCT, lactate dehydrogenase (LDH), and procalcitonin for predicting infected necrosis in patients with confirmed pancreatic necrosis 1.

Key Points

• The workup for persistent leukocytosis and pancreatitis should include a thorough history, physical examination, laboratory tests, and imaging studies to determine the underlying cause and severity of the condition.
• Lipase is the preferred enzyme for diagnosing acute pancreatitis due to its higher specificity and larger diagnostic window 1.
• CE-CT or MRI should be performed in all patients with severe acute pancreatitis to assess the severity and guide management 1.

From the Research

Workup for Persistent Leukocytosis and Pancreatitis

The workup for persistent leukocytosis and pancreatitis involves several steps, including:

• Evaluating hematological indices such as total leukocyte count (TLC), neutrophil count, lymphocyte count, and neutrophil to lymphocyte ratio (NLR) to assess the severity of pancreatitis 2
• Reviewing the patient's medical history, including the reason for admission, hospital day of consultation, peak white blood cell count, infections, and antibiotic use 3
• Conducting coagulation work-ups to detect abnormalities consistent with disseminated intravascular coagulopathy (DIC) 4
• Evaluating the peripheral blood smear to guide further testing and narrow down the differential diagnosis for leukocytosis 5
• Measuring phosphorylation levels of signal transducer and activator of transcription 1 (STAT1), STAT6, nuclear factor-κB (NF-κB), Akt, and nonstimulated STAT3 in monocytes, neutrophils, and lymphocytes to predict the severity of acute pancreatitis 6

Key Laboratory Findings

Key laboratory findings that may be associated with persistent leukocytosis and pancreatitis include:

• Elevated TLC, neutrophil count, and NLR 2
• Abnormal coagulation factors, including thrombin time, fibrinogen, D-dimers, and fibrin degradation products 4
• Presence of blasts on peripheral blood smear, which may indicate acute leukemia 5
• Elevated phosphorylation levels of STAT3 and decreased phosphorylation levels of STAT1, STAT6, and NF-κB in monocytes, neutrophils, and lymphocytes 6

Clinical Implications

The clinical implications of these findings include:

• The need for prompt evaluation and management of patients with persistent leukocytosis and pancreatitis to prevent complications such as secondary infections and organ dysfunction 2, 3, 6
• The importance of recognizing coagulation abnormalities, including DIC, in patients with acute pancreatitis 4
• The potential for leukocyte signaling pathways to predict the severity of acute pancreatitis and guide clinical decision-making 6