What could be causing my left lower quadrant abdominal pain with constipation and loss of taste, and how should I manage it?

Left Lower Abdominal Pain with Constipation and Loss of Taste

You should obtain CT abdomen and pelvis with IV contrast immediately, as acute sigmoid diverticulitis is the most common cause of left lower quadrant pain in adults and CT has 98% diagnostic accuracy. 1, 2

Understanding Your Symptom Pattern

Your combination of left lower abdominal pain with constipation strongly suggests a gastrointestinal origin, while the loss of taste is an unusual associated symptom that may represent:

• Diverticulitis - the leading cause of left lower quadrant pain in adults, affecting 5-25% of patients with diverticulosis, with prevalence increasing significantly in recent years 3
• Constipation-related pain - functional constipation can cause left-sided colicky abdominal pain that worsens throughout the day and peaks in late afternoon/evening 4
• Irritable bowel syndrome (IBS-C) - affects 5-10% of the population and presents with abdominal pain associated with altered bowel habits 5

The loss of taste is not a typical feature of these gastrointestinal conditions and may represent a separate systemic process, medication side effect, or concurrent viral illness. 6

Immediate Diagnostic Approach

Order CT abdomen and pelvis with IV contrast as your first-line imaging test - rated 8/9 (usually appropriate) by the American College of Radiology with the following advantages: 1, 2

• Detects diverticulitis with >95% sensitivity 1
• Identifies complications (abscess, perforation, fistula, obstruction) that determine whether hospitalization is needed 1
• Reveals alternative diagnoses that mimic diverticulitis clinically 1
• Guides treatment decisions between outpatient management versus intervention 1

Critical imaging findings to identify: 2, 3

• Bowel wall thickening with pericolonic fat stranding (suggests diverticulitis)
• Pericolonic lymphadenopathy >1 cm (strongly suggests colon cancer rather than diverticulitis)
• Extraluminal air or fluid (indicates perforation)
• Abscess size and location (determines drainage strategy)

Red Flags Requiring Emergency Evaluation

Send immediately to the emergency department if any of these are present: 2

• Fever combined with inability to pass gas or stool
• Severe abdominal tenderness with guarding or rebound
• Vomiting or bloody stools
• Signs of shock (rapid heart rate, low blood pressure, confusion)
• Progressively worsening pain over several days

These symptoms indicate potential complications including perforation, peritonitis, complete bowel obstruction, or sepsis that require urgent surgical evaluation. 2

Treatment Algorithm Based on CT Results

If Uncomplicated Diverticulitis is Found:

For immunocompetent patients: Conservative management WITHOUT antibiotics is appropriate - clear liquid diet advancement with oral analgesics for pain control 2

For immunocompromised or elderly patients: Antibiotics for maximum 7 days using Ertapenem 1g q24h or Eravacycline 1mg/kg q12h 2

If Complicated Diverticulitis is Found:

Small abscess (<4 cm): Antibiotics alone for 7 days without drainage 2

Large abscess (≥4 cm): Percutaneous CT-guided drainage PLUS antibiotics for 4 days 2

Perforation with peritonitis: Emergency surgical consultation for resection 2

Managing Constipation Component

If functional constipation without diverticulitis: 7

• Increasing bowel movement frequency with laxatives (regardless of mechanism) reduces abdominal pain severity
• In functional constipation, laxation alone effectively improves pain
• In IBS-C, additional visceral analgesic modulation may be needed beyond laxation

Dietary modifications to consider: 4

• Low FODMAP diet - fermentable carbohydrates can worsen IBS symptoms
• Soluble fiber supplementation
• Adequate hydration

Special Considerations for Your Loss of Taste

This symptom requires separate evaluation as it is not explained by diverticulitis or functional bowel disorders: 6

• Consider recent viral infections (including COVID-19)
• Review all medications for side effects affecting taste
• Evaluate for systemic metabolic/endocrine causes
• Consider zinc deficiency or other nutritional deficiencies

When Colonoscopy is Mandatory

Do NOT perform routine colonoscopy after CT-confirmed uncomplicated diverticulitis EXCEPT when: 2

• Pericolonic lymphadenopathy >1 cm on CT (suggests malignancy)
• Luminal colon mass visualized on CT
• Presence of abscess, perforation, or fistula
• Age-appropriate colon cancer screening not yet completed

Critical Pitfalls to Avoid

Do not rely on clinical examination alone - misdiagnosis rates are 34-68% without imaging, and the classic triad of left lower quadrant pain, fever, and leukocytosis is present in only 25% of diverticulitis cases 2

Do not miss colon cancer - perforated adenocarcinoma can perfectly mimic diverticulitis; pericolonic lymphadenopathy >1 cm is the key distinguishing feature requiring colonoscopy 3

Do not continue antibiotics beyond 7 days in uncomplicated cases - this increases antibiotic resistance without improving outcomes 2

Do not assume diverticulitis explains the loss of taste - this requires separate investigation for systemic, infectious, or medication-related causes 6