What labs should be drawn in a patient with splenomegaly, gastritis, and nausea?

Laboratory Evaluation for Splenomegaly with Gastritis and Nausea

For patients presenting with splenomegaly, gastritis, and nausea, a comprehensive laboratory workup should include CBC with differential, comprehensive metabolic panel, and specific testing for hematologic, infectious, and inflammatory disorders.

Initial Laboratory Testing (First-Line)

• Complete Blood Count (CBC) with differential and platelet count 1

  • Evaluates for cytopenias (particularly thrombocytopenia) associated with hypersplenism
  • Assesses for leukocytosis, leukopenia, or abnormal cells suggesting hematologic malignancy
  • Identifies anemia which may occur with splenic sequestration or GI blood loss

• Comprehensive Metabolic Panel 1, 2

  • Liver function tests (AST, ALT, alkaline phosphatase, bilirubin)
  • Basic metabolic profile
  • Serum lactate (if acute presentation)

• Coagulation Studies 1, 3

  • Prothrombin time (PT)
  • Activated partial thromboplastin time (aPTT)

Second-Line Testing Based on Clinical Suspicion

For Hematologic Disorders

• Serum tryptase and vitamin B12 levels 1

  • Elevated in myeloproliferative disorders, particularly those with PDGFRA fusion gene

• JAK2V617F mutation testing 1

  • Present in polycythemia vera, essential thrombocythemia, and primary myelofibrosis
  • Found in 20-40% of patients with splanchnic vein thrombosis without overt myeloproliferative disorders

• Flow cytometry and/or immunophenotyping 1

  • For suspected lymphoproliferative disorders
  • Particularly important if abnormal cells are seen on peripheral smear

• Testing for paroxysmal nocturnal hemoglobinuria (PNH) 1

  • Important acquired risk factor for splanchnic vein thrombosis

For Gastrointestinal Evaluation

• Serum gastrin levels 1

  • For suspected gastrinoma (after discontinuing proton pump inhibitors for at least 1 week)

• Helicobacter pylori testing 2

  • Stool antigen or urea breath test for suspected H. pylori gastritis

For Inflammatory/Autoimmune Conditions

• Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) 1

  • Non-specific markers of inflammation

• Antinuclear antibodies (ANA) and antineutrophil cytoplasmic antibodies (ANCA) 1

  • For suspected autoimmune disorders like vasculitis

• Serum immunoglobulin levels (including IgE) 1, 2

  • Elevated in various inflammatory and allergic conditions

Imaging Studies to Consider

• Abdominal ultrasound 1

  • Initial imaging for splenic size assessment and evaluation of portal hypertension

• CT angiography (CTA) or MR venography (MRV) 1

  • To evaluate for splanchnic vein thrombosis (portal, mesenteric, or splenic vein)
  • To assess for other abdominal pathology

Advanced Testing Based on Initial Results

• Bone marrow aspirate and biopsy 1

  • For suspected hematologic malignancy
  • Include immunohistochemistry, cytogenetics, and molecular testing

• Upper endoscopy with biopsy 2, 4

  • For direct visualization and tissue diagnosis of gastritis
  • Consider testing for Epstein-Barr virus in biopsy specimens

Common Pitfalls to Avoid

1. Failing to discontinue proton pump inhibitors before measuring serum gastrin levels, which can lead to false elevations 1

2. Overlooking splanchnic vein thrombosis as a cause of splenomegaly, which requires specific imaging techniques 1

3. Missing rare infectious causes of splenomegaly with gastritis, such as EBV infection 4

4. Not considering medication-induced gastritis as a potential cause of symptoms 2

5. Neglecting to evaluate for hematologic malignancies in patients with unexplained splenomegaly, which may present with gastrointestinal symptoms 5

By following this structured approach to laboratory evaluation, clinicians can systematically investigate the underlying causes of splenomegaly with gastritis and nausea, leading to appropriate diagnosis and management.