Laboratory Tests for Acute Left Upper Quadrant Pain
Initial Laboratory Workup
- For patients presenting with acute left upper quadrant pain, a comprehensive laboratory panel should include complete blood count, liver function tests, pancreatic enzymes, and renal function tests to evaluate for splenic, pancreatic, gastric, or renal pathology 1
- Complete blood count (CBC) to assess for leukocytosis, which may indicate infection or inflammation 2, 1
- Liver function tests (LFTs), including ALT, AST, alkaline phosphatase, GGT, and bilirubin to evaluate for hepatobiliary disease 1, 3
- Pancreatic enzymes (amylase and lipase) to rule out pancreatitis 1, 3
- Renal function tests (BUN, creatinine) to assess kidney function 1
- Pregnancy test for all women of reproductive age to rule out ectopic pregnancy or other pregnancy-related conditions 1, 3
Additional Tests Based on Clinical Suspicion
- Coagulation studies (PT/INR, PTT) if splenic rupture or hematoma is suspected 1
- Lactate level if mesenteric ischemia is suspected 1
- Urinalysis to evaluate for renal stones or infection 1
Laboratory Testing Algorithm
- First-line tests (order for all patients with acute LUQ pain):
- Second-line tests (based on clinical suspicion):
Clinical Pearls
- Elevated white blood cell count with left shift suggests infection or inflammation, which may indicate splenic abscess, pancreatitis, or diverticulitis 2, 4
- Elevated liver enzymes with a cholestatic pattern (elevated alkaline phosphatase and bilirubin) may indicate biliary pathology extending to the left upper quadrant 3
- Elevated amylase and lipase strongly suggest pancreatitis, a common cause of left upper quadrant pain 1
- Normal laboratory values do not exclude serious pathology; imaging studies may still be necessary based on clinical presentation 4