What should be done for abdominal pain, constipation, and leukocytosis?

Immediate Management of Abdominal Pain, Constipation, and Leukocytosis

This patient requires urgent CT abdomen/pelvis with IV contrast after hemodynamic stabilization to identify surgical emergencies, as leukocytosis (WBC 20) with abdominal pain and constipation suggests serious intra-abdominal pathology requiring immediate diagnosis. 1

Initial Stabilization and Risk Assessment

• Check vital signs immediately for fever, tachycardia, tachypnea, hypotension, or altered mental status, which indicate potential organ failure or sepsis requiring immediate resuscitation 1
• Establish IV access and initiate fluid resuscitation if signs of sepsis or shock are present 1
• Administer low-molecular-weight heparin for VTE prophylaxis, as acute abdominal pain carries high thrombotic risk 1

Critical Laboratory Testing

Obtain the following labs immediately:

• Complete blood count with differential (already showing WBC 20) 2
• C-reactive protein (CRP) - more sensitive than WBC alone for identifying surgical abdominal disease 2
• Serum lactate - elevated levels suggest bowel ischemia or sepsis 2, 1
• Comprehensive metabolic panel including electrolytes, liver enzymes, renal function 2
• Serum albumin to assess nutritional status and inflammation 2

The combination of neutrophilia >9.0 × 10⁹/L with lymphopenia (<1.4 × 10⁹/L) and eosinopenia (<0.04 × 10⁹/L) has 94.9% specificity for severe infectious or surgical illness requiring urgent intervention. 3

Imaging Strategy

• CT abdomen/pelvis with IV contrast is the primary imaging modality - it changes diagnosis in 51-54% of cases and alters management in 25-42% of patients 1
• Do NOT delay CT for oral contrast, as this delays diagnosis without improving accuracy 1
• Single-phase IV contrast-enhanced CT is sufficient; pre-contrast and delayed phases are unnecessary 1
• Plain radiographs have limited utility and should be avoided unless bowel obstruction is strongly suspected clinically 1

Antibiotic Decision-Making

Do NOT routinely administer antibiotics for undifferentiated abdominal pain. 2, 1

Antibiotics ARE indicated only when:

• Intra-abdominal abscess is identified on imaging 2
• Clinical signs of sepsis are present (fever, hypotension, tachycardia) 2
• Specific infection is confirmed 2

If antibiotics are needed, provide empiric coverage against Gram-negative aerobic/facultative bacilli, Gram-positive streptococci, and obligate anaerobic bacilli 2

High-Risk Differential Diagnoses to Consider

With WBC 20, abdominal pain, and constipation, prioritize these life-threatening conditions:

• Appendicitis - especially if pain migrated to right lower quadrant with fever and positive psoas sign 1
• Small bowel obstruction - particularly if history of prior abdominal surgery (accounts for 55-75% of SBO cases) 1
• Mesenteric ischemia - especially if age >60 years with atherosclerotic risk factors 1
• Perforated viscus - look for free air on imaging 1
• Intra-abdominal abscess - particularly in inflammatory bowel disease patients 2

When to Involve Surgery Immediately

Surgical consultation is mandatory for: 1

• Signs of peritonitis on physical exam
• Hemodynamic instability despite resuscitation
• Free air on imaging
• Complete bowel obstruction
• Mesenteric ischemia
• Failed conservative management of identified surgical pathology

Common Pitfalls to Avoid

• Do not rely on WBC count alone - CRP has remarkably higher sensitivity and specificity than WBC for ruling out surgical abdominal disease 2
• Do not assume normal labs exclude serious pathology - elderly patients may have normal labs despite serious infection 1
• Do not delay imaging for clinical observation - CT changes management in the majority of cases 1
• Leukocytosis can double within hours from non-infectious stressors (surgery, exercise, trauma, emotional stress), but in the context of abdominal pain and constipation, assume infectious or surgical pathology until proven otherwise 4