Letter to the Editor: Leucine-rich α-2-glycoprotein in Taiwanese inflammatory bowel disease: Strengths and limitations of a novel serum marker

Table 1 Diagnostic probability of leucine-rich alpha-2 glycoprotein, C-reactive protein, and fecal calprotectin to detect active endoscopic disease in ulcerative colitis and Crohn’s disease patients with low C-reactive protein levels

Biomarker/model	Disease group	AUROC	Cutoff	Sensitivity	Specificity	Key point
CRP	UC	0.475 (0.321-0.629)	0.045	50%	60%	Weak discrimination compared with endoscopy
LRG	UC	0.654 (0.509-0.799)	7.15	77%	53%	Modest standalone performance
FC	UC	0.779(0.656-0.903)	35	77%	73%	Best single biomarker in UC
CRP + hemoglobin-LRG	UC, low/normal CRP	0.76 (0.52-0.82)	NA	88%	49%	Improves accuracy, close to FC (0.78)
CRP	CD	0.542 (0.298-0.785)	0.025	80%	36%	Moderate performance
LRG	CD	0.517 (0.232-0.801)	7.05	80%	50%	Lower than CRP and FC
FC	CD	0.639 (0.344-0.933)	37.5	80%	58%	The highest AUC among the three in CD

AUROC: Area under the receiver operating characteristic curve; UC: Ulcerative colitis; CD: Crohn’s disease; LGR: Leucine-rich alpha-2 glycoprotein; CRP: C-reactive protein; FC: Fecal calprotectin; AUC: Area under the curve.