What is the initial treatment for left side pain?

Initial Treatment of Left Side Pain

CT scan with IV contrast of the abdomen and pelvis is the most appropriate initial treatment for left side pain, as it has superior sensitivity (95%) and specificity (96-99%) compared to other imaging modalities. 1

Diagnostic Approach Based on Clinical Presentation

Initial Assessment

• Determine the location, severity, duration, and quality of pain
• Check for associated symptoms (fever, nausea, vomiting, changes in bowel habits)
• Assess vital signs, particularly for fever or hypotension
• Perform focused abdominal examination to identify:
  • Point of maximal tenderness
  • Presence of rebound tenderness or guarding
  • Abdominal distension

Imaging Selection

1. CT Abdomen and Pelvis with IV contrast:

   • First-line imaging for suspected diverticulitis and most causes of left-sided abdominal pain 2, 1
   • Provides comprehensive assessment of disease process
   • Can identify complications such as abscess, perforation, or fistula
   • Helps stratify patients for appropriate therapy 2
   • Overall accuracy of 98% 2

2. Alternative imaging options (when CT with contrast is contraindicated):

   • Ultrasound: Consider for pregnant patients or when radiation exposure is a concern 1
   • CT without IV contrast: Reasonable alternative with rating of 6/9 for appropriateness 2
   • MRI: Limited by availability in emergency settings but has sensitivity of 86-94% and specificity of 88-92% 2, 1

3. Special populations:

   • For premenopausal women: Consider transvaginal ultrasound first if gynecologic pathology is suspected 2
   • For pregnant patients: Ultrasound is preferred to avoid radiation exposure 1

Pain Management

While awaiting diagnostic imaging:

1. Analgesics:

   • Ibuprofen 400mg every 4-6 hours as needed for mild to moderate pain 3
   • For more severe pain, consider opioids such as morphine sulfate 2

2. Supportive measures:

   • Clear liquid diet during acute phase for suspected diverticulitis 1
   • Advance diet as symptoms improve 1

Treatment Based on Diagnosis

For Diverticulitis (most common cause of left-sided pain):

• Uncomplicated diverticulitis:

  • Mild cases may be managed without antibiotics if patient has no comorbidities, no fever, and normal/mildly elevated inflammatory markers 1
  • Outpatient treatment with amoxicillin-clavulanate 875/125 mg orally twice daily for 4-7 days 1

• Complicated diverticulitis:

  • Small abscesses: Antibiotics alone
  • Large abscesses (≥3 cm): Percutaneous drainage plus IV antibiotics 1

For Other Causes:

• Epiploic appendagitis: Conservative management with analgesics 4
• Aortic dissection: Immediate blood pressure control (target 100-120 mmHg) with beta-blockers and pain management 2
• Appendicitis (rare on left side): Surgical consultation for appendectomy 5, 6, 7

Follow-up and Monitoring

• Reassess in 48-72 hours if outpatient management is chosen 1
• For diverticulitis, consider colonoscopy 6-8 weeks after symptom resolution to rule out colon cancer 1
• Monitor for warning signs requiring immediate medical attention:
  • Development of fever
  • Worsening abdominal pain
  • Inability to tolerate oral intake
  • Signs of peritonitis (rigid abdomen, rebound tenderness) 1

Clinical Pearls

• Left-sided pain has a broad differential diagnosis including diverticulitis, colitis, inflammatory bowel disease, epiploic appendagitis, and urolithiasis 2
• Elderly patients may present with atypical symptoms - only 50% of patients >65 years have pain in lower quadrants, 17% have fever, and 43% do not have leukocytosis 1
• The classic triad of left lower-quadrant pain, fever, and leukocytosis is present in only 25% of patients with diverticulitis 2
• Rare causes of left-sided pain include situs inversus with appendicitis, which can be easily missed without appropriate imaging 6, 7