Guideline Recommendations for Evaluating a Low Albumin/Globulin Ratio in Patients with Ulcerative Colitis and Ankylosing Spondylitis

Biomarker Assessment

• Measure fecal calprotectin in all patients; a value < 150 mg/g is expected in remission of ulcerative colitis. This threshold helps identify subclinical intestinal inflammation. 1
• Serum CRP alone may be insufficient to exclude moderate endoscopic inflammation in patients who are clinically in remission. Normal CRP can miss active disease. 1
• Liver function tests (including albumin synthesis markers) should be obtained to evaluate hepatic contribution to a low A/G ratio. Recommended for comprehensive assessment. 4

Ulcerative Colitis – Decision Thresholds

• If fecal calprotectin > 150 mg/g or CRP is elevated, an endoscopic examination is indicated to rule out occult mucosal inflammation. This approach directs timely therapeutic escalation. 1
• When fecal calprotectin > 150 mg/g or CRP remains high, histologic sampling should be added to the endoscopic work‑up. Provides definitive assessment of disease activity. 4
• If fecal calprotectin < 150 mg/g and CRP is normal, repeat biomarker testing in 3–6 months is advised; persistent elevation then warrants endoscopy. Supports a stepwise monitoring strategy. 1
• Fecal lactoferrin may be used as an adjunct biomarker for intestinal inflammation. Offers an alternative when calprotectin is unavailable. 2

Ankylosing Spondylitis – Complementary Evaluation

• Spinal imaging (MRI) should be considered when clinical assessment suggests active disease despite low A/G ratio. Helps quantify extra‑intestinal inflammatory burden. 4

Management Algorithm

Step 1 – Immediate Assessment

• Obtain fecal calprotectin and serum CRP promptly to stratify risk. 1

Step 2 – Stratification Based on Biomarkers

• Low‑risk profile (calprotectin < 150 mg/g + normal CRP):

• High‑risk profile (calprotectin > 150 mg/g or elevated CRP):

Step 3 – Investigate Causes of Low Albumin

• Assess renal function for proteinuria to exclude nephrotic loss of protein. 5

Limitations of CRP

• Normal CRP does not reliably exclude moderate endoscopic inflammation, especially shortly after remission induction. Clinicians should not rely solely on CRP to declare mucosal healing. [1][2]6

Refined Fecal Calprotectin Thresholds

• In patients who have achieved remission within the past 1–3 months, a lower calprotectin cut‑off (< 50 mg/g) more accurately predicts endoscopic healing than the standard < 150 mg/g threshold. 2

Need for Endoscopic Confirmation

• Distinguishing symptomatic remission from true mucosal healing requires endoscopic and histologic confirmation, regardless of biomarker trends. [1][4]