Elevated Neutrophils in Females with Upper Abdominal and Back Pain
Elevated neutrophils in a female with upper abdominal and back pain most commonly indicates an acute infectious or inflammatory process, with bacterial infection being the primary concern—particularly acute cholecystitis, pancreatitis, pyelonephritis, or intra-abdominal abscess. 1
Primary Infectious Causes
The most likely etiologies based on anatomic location include:
Biliary Tract Disease
- Acute cholecystitis is a common cause of right upper quadrant pain with neutrophilia, often accompanied by fever and elevated inflammatory markers 2
- Cholangitis presents with cholestasis, right upper quadrant pain, jaundice, and radiological evidence of biliary obstruction, triggering significant neutrophil elevation 2
- Bacterial infections, particularly with organisms like E. coli and Staphylococcus aureus, are the most common causes of neutrophilic leukocytosis with left shift 1
Pancreatic Disease
- Acute pancreatitis causes upper abdominal pain radiating to the back with marked neutrophilia due to tissue inflammation and necrosis 1
- Pancreatic abscesses or infected necrosis can develop, particularly when neutrophil counts are markedly elevated (>15,000 cells/L) 1
Renal/Urologic Sources
- Pyelonephritis or perinephric abscess can present with flank/back pain and upper abdominal discomfort with significant neutrophilia 2
- Urinary tract infections are diagnosed by abnormal urinary sediment (>10 leukocytes/field) and positive culture 2
Severity Assessment
The degree of neutrophilia and presence of left shift provide critical diagnostic information:
- Band neutrophils >16% have a likelihood ratio of 4.7 for bacterial infection 1
- Neutrophil percentage >90% has a likelihood ratio of 7.5 for bacterial infection 1
- Total band count >1,500 cells/mm³ has high likelihood for documented bacterial infection 1
- WBC >20,000 cells/mm³ is associated with increased mortality in bloodstream infections and suggests severe sepsis 1
Intra-Abdominal Infections
Peritoneal Infections
- Spontaneous bacterial peritonitis (in cirrhotic patients) is diagnosed when ascitic fluid neutrophils exceed 250/mm³ 2
- Secondary peritonitis shows neutrophils >250/mm³ (frequently >10,000/mm³) with additional criteria including low glucose, elevated protein, and evidence of intra-abdominal source on CT 2
- Abdominal abscesses are well-detected by CT with IV contrast, which should be the initial imaging modality when infection is suspected 2
Non-Infectious Inflammatory Causes
While less common, consider:
- Alcohol-related hepatitis can present with upper abdominal pain and neutrophil infiltration on biopsy, with neutrophilia in peripheral blood 2
- Systemic inflammatory disorders including vasculitis can cause neutrophilia, though typically with additional systemic features 1
- Solid tumor necrosis or obstruction may cause reactive neutrophilia 1
Critical Diagnostic Approach
When evaluating neutrophilia with upper abdominal/back pain:
Assess severity markers immediately: total WBC, absolute neutrophil count, band percentage, and presence of toxic granulation 1
Obtain imaging based on clinical suspicion:
Culture appropriately: Blood cultures, urine cultures, and diagnostic paracentesis if ascites present 2
Common Pitfalls
- Do not dismiss normal imaging with high neutrophilia—early infection may not show radiographic changes initially 2
- Neutrophilia without fever does not exclude infection—elderly or immunocompromised patients may not mount fever response 2
- Left shift with bandemia is more specific than total WBC alone for bacterial infection 1
- In postoperative patients, consider anastomotic leak or abscess even days to weeks after surgery 2