What is the diagnosis and recommended management for a patient with chronic pancreatitis presenting with epigastric pain radiating to the back, leukocytosis (white‑blood‑cell count 14.1 ×10⁹/L) and normal AST, ALT, and alkaline phosphatase?

Diagnosis: Acute-on-Chronic Pancreatitis

This patient with known chronic pancreatitis presenting with epigastric pain radiating to the back and leukocytosis (WBC 14.1) most likely has an acute exacerbation of chronic pancreatitis (acute-on-chronic pancreatitis), and requires immediate measurement of serum lipase or amylase, abdominal imaging, and assessment for complications including infection.

Diagnostic Approach

Biochemical Confirmation

• Measure serum lipase immediately (preferred over amylase as it remains elevated longer and has higher specificity) - diagnosis requires lipase >2 times upper limit of normal in the appropriate clinical setting 1
• If lipase is equivocal, obtain urinary amylase activity 1
• The leukocytosis (WBC 14.1) may represent either inflammatory response to pancreatitis or early infection - rising leukocyte counts suggest possible sepsis 2
• Normal AST, ALT, and alkaline phosphatase make biliary obstruction or cholangitis less likely, but do not exclude gallstone etiology 3

Imaging Strategy

• Obtain abdominal ultrasound immediately to evaluate for gallstones (the most common cause of acute pancreatitis, accounting for ~50% of cases), assess pancreatic swelling, detect fluid collections, and identify any biliary duct dilatation 1, 3
• If ultrasound is inconclusive or clinical suspicion for complications is high, proceed to contrast-enhanced CT scan to assess for pancreatic necrosis, fluid collections, or abscess formation 1, 2
• In acute-on-chronic pancreatitis, pancreatic enzyme levels may be less than 3 times the upper limit of normal, making cross-sectional imaging particularly important for diagnosis 4

Severity Assessment

• Calculate severity scores (Glasgow, APACHE II, or Ranson) within 48 hours to stratify risk 3
• The WBC count of 14.1 is a component of severity scoring and warrants close monitoring 5
• Assess for organ failure indicators: monitor urine output (target >0.5 ml/kg/hr), respiratory status, and hemodynamic stability 2

Evaluation for Infection

Critical Red Flags

• Low-grade fever in necrotizing pancreatitis does NOT automatically indicate infection and does not warrant antibiotics 2
• However, sudden high-grade fever, prolonged ileus, abdominal distension, persistent tenderness, or failure to improve clinically are red-flag signs requiring urgent investigation for infected necrosis or abscess 2

Infection Workup (if fever or clinical deterioration present)

• Obtain blood cultures, and when indicated, sputum and urine cultures to rule out non-pancreatic sources of infection 2
• Perform chest radiograph to detect pneumonia, pleural effusion, or ARDS 1, 2
• If sepsis is suspected, repeat contrast-enhanced CT more frequently than the routine 2-week interval to evaluate for infected necrosis, abscesses, or pseudo-aneurysms 2
• Consider radiologically-guided fine-needle aspiration (FNA) with microscopy and culture only if intra-abdominal sepsis is strongly suspected and performed by experienced radiologists 2

Management Algorithm

Initial Supportive Care

• Goal-directed fluid resuscitation with balanced crystalloids (Lactated Ringer's solution): initial bolus 10 ml/kg followed by 1.5 ml/kg/hr, with total crystalloid <4000 ml in first 24 hours 2
• Monitor urine output targeting >0.5 ml/kg/hr 2
• Pain control: start with NSAIDs and weak opioids (tramadol) as first-line therapy 6
• Trial of pancreatic enzymes and antioxidants (multivitamins, selenium, methionine) can control symptoms in up to 50% of patients 6
• Advise immediate cessation of alcohol and smoking - both are major risk factors for acute exacerbations 6, 7

Antibiotic Decision Tree

• NO prophylactic antibiotics - routine prophylactic antibiotics provide no benefit even in necrotizing pancreatitis without documented infection 2
• START antibiotics ONLY if:
  • Documented infection identified (pneumonia, UTI, line-related sepsis, cholangitis) 2
  • Confirmed infected necrosis/abscess/fluid collection on FNA 2
• If infected necrosis confirmed: use pancreatic-penetrating antibiotics (imipenem or cefuroxime) and plan drainage (percutaneous, endoscopic, or surgical) 2

Disposition Based on Severity

• Mild pancreatitis (80% of cases): manage on general ward with basic monitoring, peripheral IV access, possible nasogastric tube 3
• Severe pancreatitis (20% of cases): transfer to ICU/HDU with full monitoring and multidisciplinary approach 3

Etiology Investigation

Essential Workup

• Thorough history focusing on: previous gallstones, alcohol intake (OR 3.1 for ≥5 drinks/day), smoking history (OR 4.59 for >35 pack-years), family history, medications, and viral exposures 3, 6
• Fasting lipid panel and calcium levels (if gallstones and alcohol excluded) - triglycerides >11.3 mmol/L indicate hypertriglyceridemia as cause 3
• Hypocalcemia (<2 mmol/L) is a negative prognostic factor indicating severe disease 3

Gallstone-Specific Management

• If gallstones identified with severe pancreatitis, cholangitis, jaundice, or dilated common bile duct: urgent ERCP within 72 hours 3
• Plan cholecystectomy during same admission or within 2 weeks for mild cases to prevent recurrence 3

Common Pitfalls to Avoid

• Do not assume any fever equals infection - low-grade fever in necrotizing pancreatitis is common and does not merit antibiotics 2
• Do not drain asymptomatic fluid collections - more than 50% resolve spontaneously and unnecessary drainage can introduce infection 2
• Do not accept "idiopathic" diagnosis without vigorous search for gallstones (at least two quality ultrasounds) 3
• Do not rely on clinical findings alone - diagnosis of acute pancreatitis based solely on pain and tenderness is unreliable 1
• In acute-on-chronic pancreatitis, enzyme levels may be less elevated than in acute pancreatitis, requiring lower threshold for imaging 4